This report is a historical review of high-speed processes investigations in Russia.

Sometimes called 'The father of the motion picture,' Eadweard Muybridge made an unforgettable contribution to the development and progress of photographic science. This Paper traces his life, from his birth in England in 1830, through his development as a photographer in the United States, his acknowledgement as a photographic pioneer in America and Europe and his latter years until his death in England in 1904. It concentrates on his work in the USA during which time he pioneered his famous series of studies of animals and human beings in motion. These were carried out in two main periods, firstly in California under the patronage of Stanford and then later at the University of Pennsylvania where further sponsorship funds became available. As with all good experimentalists he steadily improved both his methods and equipment. He not only developed the methods of obtaining multiple sequential photographs of moving subjects, but also went on to invent the Zoopraxiscope by which these photographs could be projected to produce an early form of quasi-cine viewing. During his most productive years in the United States, he took thousands of pictures covering an enormous variety of animal and human motion. Many of his photographs were published in collected form and, unlike many early photographers whose work was lost or destroyed after their deaths, his work can still be studied as an indispensable aid to artists and physiologists.

Antic scientists, sailors, warriors, physician, etc. were perceiving the space by means of their eye vision system. Nowadays the same people use eyeglasses, telescopes, microscopes, image converters. All these devices fit the necessary magnification, intensification gain and image spectrum to the eyes. The human brain is processing the image data offered to him in a format pertaining to eyes. Hence, the cognition of images can be regarded as a direct measurement. As to the time scale converters, they turned out to be harder done as compared with the spatial scale converters. Hence, the development of the high-speed photography (HSP) continues for more than a hundred and fifty years. The recent pico- femtosecond HSP branch sprang up in 1949 at the Kurchatov Institute -- its cradle. All about the HSP had been advertised. Instead of reprinting what is already well known, it makes sense to emphasize some instructive lessons drawn from past experience. Also it is tempting to look a bit into the high-speed photography future.

AIRIX is an induction linear accelerator which will be used for flash radiography in CEA/DAM. Designed to produce an X-ray dose of more than 500 Rads at 1 meter with an X-ray focal spot size diameter of less than 2 mm (LANL-CEA DAM definition), this facility consists in a 4 MeV/3.5 kA pulsed electron injector and 16 MeV induction accelerator powered by 32 high voltage generators. A prototype of this accelerator, called PIVAIR, has been studied and realized in CEA CESTA near Bordeaux. PIVAIR is a validation step for AIRIX at 8 MeV. It includes an injector (4 MeV, 3.5 kA, 60 ns) and 16 inductor cells supplied by 8 high voltage generators (250 kV, 70 ns). Two different technologies of induction cells have been tested (rexolite insulator or ferrite under vacuum). We have chosen ferrite under vacuum cells technology after comparison of results on beam transport and reliability tests. A focusing experiment at 7.2 MeV of the electron beam as been achieved during summer 1997. We have begun to produce X-rays in October 1997. A dose level of 50 Rad at 1 meter has been achieved with an X-ray spot size diameter of 3.5 to 4 mm (LANL-CEA DAM definition). Static flash radiography of very dense object have been achieved from November 97 until February 98. We have been able to test in situ new kinds of very high sensitive X- ray detectors and to check they had reached our very ambitious goals: (1) quantum efficiency at 5 MeV greater than 50% instead of 1% for luminous screens and film; (2) sensitivity less than 10 (mu) Rad (100 time more sensitive than radiographic luminous screens and films); (3) dynamic range greater than 100; (4) resolution less than 2 mm. We will present in this communication brand new kinds of detection systems, called high stopping power detectors, such as: (1) (gamma) camera with segmented thick crystal of BGO and MCP image intensifier; (2) multistep parallel plate avalanche chamber; (3) pixellized CdTe MeV photoconductor matrix. AIRIX accelerator is being built by THOMSON CSF Company in CEA Moronvilliers near Reims. It is housed in a reinforced concrete bunker and has an overall length of 60 meters. The 20 MeV electron beam will be focused on a 1.5 mm thick Tantalum target to produce an X-ray fluence (flux) of more than 500 Rads one meter from the target. The result is a single radiograph of the device explosion under test with the high stopping power detector located in a blast protection set behind the device. In this communication we will present all these techniques which correspond to a significant effort of CEA begun in 1992. AIRIX facility will be available to run detonics experiments before end of 2000.

Main emphasis of the laser-target effect investigations to be reported in the present paper was related to characterize and to improve methods for enhancing the energy transfer rates by thermal conduction, radiation, recombination or recondensation. It was especially aimed to study the behavior of optically transparent dielectrical materials, subject to temporally strongly modulated high average power laser radiation. Experimental studies were carried out on samples either transparent in the visible or in the infrared spectral range. A large range of laser irradiation conditions was provided by a novel repetitively pulsed CO₂-laser. This laser provides average powers up to 15 kW. Pulse energies up to 150 J per pulse and peak powers close to hundred MW (for typical pulse durations of 2 microseconds to 10 microseconds) are achieved at any repetition rate up to 100 pps. Rather uniform power densities (with peak to average values ratios of 10³ to 10⁴) were established across large area surfaces quasi-one-dimensionally. Focusing conditions were adapted to specific experimental requirements. High speed photographic diagnostics including high speed videography, laser interferometry and laser moire techniques have been used and compared to provide information on thermal and thermomechanical plasma-induced processes, on damage thresholds and on basic physical mechanisms involved.

The principle of holography was invented by Dr. Gabor in 1948 before the invention of the laser. In 1962, after the invention of laser (in 1960: the first demonstration of laser oscillation by Maiman was achieved using a ruby cubic crystal), the off-axis reference beam holography was developed by Prof. Leith and Mr. Upatnieks. One of the most useful measuring techniques of the holography is a holographic interferometry. Holography enable to storage signal wave fronts and reconstruct it at later time, then the interference between the reconstructed signal wave fronts and the wave fronts come from the object to be able to generate an interference fringes. Real-time holographic interferometry can measure real-time phase-change of phenomena. Therefore, this method has the performance of continuously measuring phase change by coupling with high-speed cameras.

In so-called cavity charges superfast jets with tip velocities in the range of 25 km/sec are found. Such fast jets are strongly eroding by the perforation of the ambient air. The ablated jet material forms a tube around the jet and is optically protecting the core of the jet itself. With tests, where the jet is elongating in vacuum, this problem does not exist or is drastically reduced. To get enough space resolution, the profile streak technique (PST) was used to obtain the diameter of the stretching jet as a function of the passing time or with respect to its velocity gradient. With this special diagnostic technique the radius of these superfast jets was measured the first time. The used test method with typical results together with the applied evaluation technique will be described.

A transmission framing electron microscope which consists of a lanthanum hexaboride cathode, two focusing lenses, an object lens, an intermediate lens, a projective lens, a scan deflector, a two-aperture-plate, a two compensation deflectors, a fiber plate based phosphor screen, an image intensifier, and a CCD readout system, is constructed based on a DX-4 transmission electron microscope. Two framing micrographs each in the size of (phi) 10 mm, with magnification of 10,000 have been obtained. Under the current condition, the exposure time of 43 ns (FWHM is 21.5 ns) has been achieved. The spatial resolution is evaluated by edge spread function and is proved to be 14.4 nm limited by the CCD readout system. Apart from the technical problems, the physical limitation and the potential of the framing electron microscopy are discussed, indicting that the temporal resolution of 100 ps and the spatial resolution of 10 nm can be achievable. The experimental results and the analysis show the potential of the application of the framing electron microscopy in the related research area.

We report on development and preliminary tests of a sub- picosecond soft x-ray streak camera. The time response of the streak camera measuring with a sub-100 fs laser pulse at center wavelength of 400 nm was about 0.5 ps FWHM.

We report on development of the super small single streak and single frame image converter camera, which has nano- submillisecond range of streak and frame duration.

Because of computing algorithms realizing a method of finite groups, it is on the personal computer the numerical analysis of models of real essential three-dimensional constructions of electron-optical systems of various assignment in electrostatic and quasistatic approximation, in a mode of a travelling-wave in real time can be carried out. The used methods are described, the example multicascade EOS, including electrodes various configuration, deflecting and calibrating plates and diaphragm system is reduced.

Effectiveness decrease of the phosphor screens of the P11 and P20 types for streak tubes in the picosecond region is shown. It is shown that the complete amplification of the circuit 'streak tube + image intensifier + CCD' in the picosecond region is the same as one of the circuit 'streak tube + etched CCD instead of the screen in a whole volume,' though the static amplification in the first case is by two orders higher. A special streak tube of the PV series has been manufactured. The screen of this tube consists of 4 various phosphor screens prepared on the same fiber-optical disk in the form of closely placed strips of 5 mm width: K-71 (blue), K-78 (green), 'cadmium' (green), IL-3P (red). A streak tube with the phosphor screen KL3-2 (green) has also been investigated. Principal scheme of the experiment is shown in Figure 1. In these experiments, the voltage between the tube's photocathode and screen was of 14 KeV, photocathode current density approximately 100 (mu) A/mm², and duration of the pulse initiating the photocathode -- of 10^-7 s. The shape of the phosphor screen irradiation response is presented in Figure 2 as an oscillogram. For each phosphor screen type the oscillogram is normalized to unit. In Table 1, the time intervals are presented during which the phosphor screen is lighting up being excited by current pulses of 10^-7 s. With the use of the phosphor screen decaying curves it is possible to determine the duration of time during which the image amplifier (usually with MCP) should remain open being placed in the electron-optical camera between the streak tube and readout system. The time interval, during which about 70% of the lightsum for phosphor screens of three types are lighting up, is presented in Table 2. Taking into account that high noise level is inherent to the image intensifiers with MCP, it is advisable to use in streak tubes the phosphor screens with minor lighting-up time duration, and to turn on the MCP for a minimal required time. In the Russian streak camera 'Agat' this time is equal to (6 - 8) (DOT) 10^-4 s, which significantly exceeds the required time.

Hybrid Image Tubes (HIT), being Image Intensifiers (II), output cathode-luminescent screen of which is replaced by periodic structure of semiconductor electron-sensitive elements (ESE), meet more and more wide application in the fields where it is necessary to receive and process weak optical images (illumination level of about 10^-6 lx). In this connection it is expedient to estimate HIT as photon counter, more precisely as photon group counter (with photons number in the group (gamma) ^-1, where (gamma) -quantum output of the used photocathode on a certain wavelength). One- electron (counting) registration mode is possible if impulse amplitude at ESE output exceeds fixed level of amplitude discrimination which cuts off measuring equipment noise together with ESE noise. This imposes strict requirements on coefficient of amplification value of element K_amp and on dispersion D of output impulses amplitudes.

We have developed and investigated a Hybrid Image Converter Tube (HICT) with S-25-input photocathode and electron- sensitive elements (ESE) of 0,42 X 0,25 mm² size for the purposes of astronomic spectroscopy.

Three principles of building high sensitive (low-level) converters of a TV-type are well known. They are based on the following: (1) usage of electron-optical image converters (IC) as input image amplifiers and its converting into a TV signal by commercial TV cameras (Fig. 1a); (2) location in a single vacuum volume of a receiving input part of IC with a diode silicon substrate -- a storage target -- in which a photoelectric image is being amplified (amplification factor is 100 . . . 300) and then is read out by an electron beam with the energy corresponding with the condition (sigma) less than 1 ((sigma) -- secondary electron emission coefficient). The converter developed on the base of this principal has got the name of superkremnikon (a super silicon-imaging device) (Fig. 1b); (3) location in a single vacuum volume of a receiving part of IC, amplification microchannel plate (MCP) with amplification factor 100 . . . 1000 and a CCD with amplification equal to 100 (Fig. 1c). One should take into account the following disadvantages of the above-mentioned devices of a TV-type: (1) not high linear resolution of an input image, caused by multiple conversion of an input image - - (2.2 . . . 3.5)(DOT)10² lines in the middle of a target; (2) inadequately high sensitivity, defined basically by optical losses. Limiting sensitivity within the visible range has been realized at superkremnikon (10^-7 lx) coupled with an input IC through fiber-optical communication; (4) high cost of the converters, which is limiting their wide practical application for the purposes of medical diagnostics and non- destructive control. The alternative principle of building the high sensitive converters of a TV-type, based on a new method of energy radiation image conversion within a wide spectral range into an electrical (including TV) signal is proposed. In the frames of the new method the MCP is operating at the same time as a receiver, an amplifier and a two-sided storage target on reading out. A conventional image of the converter is given.

Classically-designed X-ray image intensifiers, in which the primary converter of X-ray image (X-ray luminescent screen) is placed inside the vacuum space of the X-ray image intensifier, and the photocathode converting light image into electronic one is in optical contact with the primary converter, have decisively displaced a combined systems -- external X-ray luminescent screen, light-transmission optics, image intensifier -- from medical and industrial X-ray diagnostic devices since they possess essentially higher luminance amplification (higher X-ray-to-light image conversion coefficient) and higher signal-to-noise ratio. We have assumed that this conversion coefficient is determined as a ratio of luminance of light image at the output screen of the X-ray image intensifier (measured in cd/sq.m.) to intensity of the X-ray radiation at the input of the X-ray image intensifier, derived from the power of the exposure dose (in R/sec). When we analyzed an X-ray-to-light image conversion dependence, we found out that there is an inconsistency between a method of measuring the efficiency of this conversion and this dependence such that the power of the exposure dose determines absorption of X-ray radiation only in the air and can not be recalculated into absorption in components of the X-ray image intensifier. In order to solve these contradictions, in this paper we have considered spectral X-ray characteristics. We further developed assumptions that the spectral density of the power flow of bremsstrahlung X-ray radiation depends linearly on the quantum power of this radiation. We succeeded in relating this dependence with the power of the radiation exposure dose and in obtaining a family of spectral characteristics of bremsstrahlung X-ray radiation at different anode voltages of the X-ray tube for a certain exposure dose. The paper describes calculations of the total power flow of the bremsstrahlung X-ray radiation at the input of the X-ray image intensifier, calculations of absorption of this flow in the functional assemblies of the X-ray image intensifier -- in the input window made of different materials (glass, aluminum, beryllium, steel, and glass-carbon) and in the X-ray luminescent screen made of iodine cesium. We have calculated values for the conversion coefficient of the X-ray image intensifier on the whole.

We proposed and developed a detector for on line non- destructive monitoring of geometrical parameters of ionizing beams. The detector gives the size of a beam cross-section, cross-section density distribution, position of the cross- section gravity center and its displacement. The detector contains electrostatic extractor and analyzer as well as open Image Converter Tube (ICT) ICT is made of two Micro Channel Plates (MCP) with luminescence screen. Detector is placed within beam line at residual gas pressure 10^-4 - 10^-6 Torr. The residual gas works as a target. Electron optic analyzes ions on energy, which they get in extractor electric field. The ion picture of the beam under investigation is put on input MCP. The screen of the ICT forms image of the beam. TV camera registers this image. Then the image is processed in a computer. Computer processing gives one the possibility to have numeric beam parameters. Statistical processing makes the sensitivity better and estimates displacement of the beam with the accuracy of order of a few microns. The detector was investigated on different particles accelerators and on synchrotron radiation sources. Modified detector gave a possibility to measure microstructure of cyclotron beam. The detectors can be used on scientific and industrial accelerators.

This paper considers the question of extending capabilities of the instrument KIT-2F for recording high-speed events in the IR region at (lambda) equals 1 - 10.6 micrometer with the exposure times of 10 ns - 1 microsecond(s) by using an image converter (IC) based on the MCP both as a fast shutter and an image intensifier. It is shown that in recording high-power IR laser radiation the exposure time has been reduced down to (tau) _{exp min} approximately 10 ns without degrading the image quality. It has been found out that in the mode of limiting sensitivity when weak thermal IR signals are recorded, there is a limitation both on maximum and minimum exposure times. The maximum exposure time is limited by the internal thermal background of the photo-detector and the minimum exposure time by the insufficiency of statistics on the recorded signal leading to a loss in the resolving power of the instrument. It is shown that KIT-2F interfaced with the IC permits to record objects heated to temperature t equals 700 degrees Celsius at the exposure time (tau) _exp greater than or equal to 100 ns.

In process of making several new kinds of high speed intermittent camera, in order to obtain the perfect frame stability which is important for good quality of the pictures, the film-down-rushing law and equistroke film transporting have been studied, theoretically and experimentally.

This paper introduces a high speed single-mirror scanner developed by us as a versatile tracker. It can be connected with a high speed camera, a TV tracker (or color video recorder) /measurer/recorder. It can be guided by a computer, a joystick (automatic or manual) or TV tracker. In this paper, we also present the advantages of our scanner contrasted with the limitations of fixed camera system. In addition, several usable projects of mirror scanner are discussed.

The paper describes our research on infrared-sensitive streak camera that adopts a streak tube with a complex photocathode which consists of a membrane made of up-converting material (one kind of ET material) and a S-20 photocathode. The up- converting screen is able to convert 800 nm - 1600 nm infrared radiation to visible light. The peak values of the converting efficiency are located at 1165 nm for CaS:Eu, Sm and 1060 nm for CaS:Ce, Sm. We obtained a novel result of time resolution of the ET-materials and the streak camera attains time resolution of 12.3 ps for CaS:Eu, Sm screen and 8.4 ps for CaS:Ce, Sm screen.

A new metal-resistive layer-semiconductor avalanche photodiode for single photon detection was designed and produced. High efficiency of single photon registration at room temperature was achieved. These devices also show the possibility of recording short light pulses with front duration as low as 5 ps.

The threshold value of the energy density q_thr at wavelength of 1.06 micrometer which led to unrecoverable sensitivity loss of the first generation S-1 photocathode of single-chamber module image converter tube (ICT) with fiber disks at input and output was determined experimentally. The value amounted to 2 X 10^-2J/cm².

When using diodes with Al-(i-GaAs) - (n-GaAs) Schottky barrier under electron beam as amplifying structures there was obtained abnormally high coefficient of cathode amplification K_amp approximately equals 25000 under electrons energy of 10 keV and application of bias voltage in the straight direction (plus to aluminum contact radiated by electrons) of about 0,8 V. In fig. 1 there is given electro-sensitive structure (ESS) radiated by electrons with energy of 10 keV. High-ohm (10⁹ Ohm x cm) i-GaAs was forming by radiation of ions Ar with dose of 3 x 10¹³ ion/cm² and energy of 30 keV in n-GaAs (n equals 10¹⁶ cm^-3). Thickness of Al-contact was 0,1 micrometer, thickness of i-layer was 1 micrometer. ESS size was 0,42 x 0,25 mm². Under traditional reverse bias to 2V diode, structure parameters were: dark current I_T equals 1nA, capacity C equals 7 pF, K_amp equals 1600 under electrons energy of 10 keV. In fig. 2 there is shown K_amp dependence on bias voltage U_b under energy of radiating electrons 10 keV. Here and further, positive values of U_b corresponds to direct bias, negative values - to reverse bias to ESS. In fig. 2 it is seen that there is dependence maximum under U_b equals 0,8V and K_amp is 25000. Here is available abnormally high cathode amplification of presented ESS. Actually, taking into account that generation energy of electron-hole pair in i-GaAs is equal to 4,8eV we will obtain that even in ideal case (under reduction of energy losses in 'dead' layer to zero and full collection of unbalanced charge carriers) under radiating electrons energy of 10 keV, K_amp will be a value of about 2000. Additional cathode amplification (more than by an order) was obtained in our view due to operation of injecting n-i- transition. Actually, in i-GaAs Fermi level is near the middle of semiconductor forbidden zone, in n-GaAs -- near the bottom of conductivity zone, i.e. at the limits of n and i-regions there is formed a potential barrier. Under application of bias voltage to ESS practically all voltage falls to i-region due to i-GaAs high specific resistance. In i-region before n-i- transition for holes there is formed a potential pit. When radiating by electron flow in i-region there occurs generation and division of charge carriers pairs: electrons flow to electrode under positive potential (collector), holes are accumulated in potential pit near n-i-transition. Accumulation of holes positive charge leads to reduction of potential barrier and additional injection of electrons from n to i- region. Injected electrons are transferred by the field to collector and give current increase in the outer circuit that enables additional signal amplification in ESS.

Description both mobile and stationary multifunction set of optical research equipment created for investigations in wind tunnel are presented. Mobile equipment has field of vision up to 500 mm in diameter, stationary -- up to 1000 mm. Examples of interferograms, shadowgraphs and holograms, created in wind tunnel from subsonic to hypersonic velocities (0.1 less than M less than 16) are produced. Equipment gives opportunity to register nonstationary processes up to 30 nanosecond duration.

Helicopter's blade during its rotation accomplishes a complex spatial movement and deformation. This report is devoted to Blade Deformation Measuring System (BDMS) which was developed to measure parameters of the real-scaled blade movement and its bending-twisting deformation. This system operates under videogrammetry principles. The basic principles of registration of video-images and processing of results of measurements are stated. Brief description of the system design is given. The results of the laboratory investigations of system features are discussed as well. This system was tested during experimental investigations of blade deformations of the real upper rotor of Kamov-26 helicopter with radius 6.5 m on the VP-5 rotor test facility in TsAGI's T-101 wind tunnel. The tests have confirmed serviceability of system and have shown opportunity of twist deformation measurements of the blade with a root-mean-square error lower 3 - 6 angular minutes and bend deformations measurements with an error of 0.3 - 0.6 mm. The technique of calibration of Blade Deformation Measurement System and appropriate software had been developed and tested.

Results of optic investigation spacional and near-wall streams which was realized at wind tunnel tests of two models are presented. The first was the model of maneuverable airplane, second was the model of airfoil with free streamline (Schmieden's airfoil). Some nonstationary processes on Schmieden's airfoil are registered. Ambient stream velocities varies from 20 to 50 m/s.

Luminescent Pressure Sensor Technology is a new optical pressure measurement method providing new opportunities for non-contact pressure measurements, for example on the blades of rotating propellers. Specific features of LPS-technology for propellers are discussed. A prototype optical pressure measurement system for propellers and operational procedure are described. Results of pressure measurements on two propellers at zero and non-zero angles of attack are presented.

Pressure enhancement of the generated shock waves in water has been found, when pulse laser energy is transmitted through an optical fiber whose end surface is intentionally roughened. More effective high-pressure shock generation can be possible by the aluminum coating on the roughened fiber surface. In case of the moderate laser energy of about 50 mJ input to the fiber, it is found that the phenomena are dependent on (1) the roughness, (2) the fiber diameter, and (3) the ambient medium. Shock wave generation can be detected successively by the laser input, but found to degrade down. Cavitation bubbles have also been observed after each shot. When the fiber end is in air, an intense and long-stretched flash can be observed. We have observed the phenomena by the pulse laser shadowgraphy.

Precision optical observation method was developed to study impact-generated high-pressure shock waves in condensed materials. The present method makes it possible to sensitively detect the shock waves of the relatively low shock stress around 0.5 GPa. The principle of the present method is based on the use of total internal reflection by triangular prisms placed on the free surface of a target assembly. When a plane shock wave arrives at the free surface, the light reflected from the prisms extinguishes instantaneously. The reason is that the total internal reflection changes to the reflection depending on micron roughness of the free surface after the shock arrival. The shock arrival at the bottom face of the prisms can be detected here by two kinds of methods, i.e., a photographic method and a gauge method. The photographic method is an inclined prism method of using a high-speed streak camera. The shock velocity and the shock tilt angle can be estimated accurately from an obtained streak photograph. While in the gauge method, an in-material PVDF stress gauge is combined with an optical prism-pin. The PVDF gauge records electrically the stress profile behind the shockwave front, and the Hugoniot data can be precisely measured by combining the prism pin with the PVDF gauge.

Hugoniot curves for several polymeric materials in the stress region of 0.5 GPa are measured by two methods developed for this purpose. High-speed photography or in-material gauge method is used combined with new prism technique based on the principle of total internal reflection. We measured the following materials, i.e., polymethylmethacrylate (PMMA), three kinds of polyethylene (PE specimens), polytetrafluoroethylene (PTFE), nylon 6 (N6), polycarbonate (PC), polypropylene (PP), polyvinylchloride (PVC). All of the Hugoniot curves are found to be nonlinear. In particular, three kinds of PE specimens are measured in detail, which have the different density, crystallinity, molecular weight distribution and manufacturing process. It is found that these PE specimens have different Hugoniot curves, but qualitatively similar.

For the past years we have developed several optical techniques to measure properties of shock waves. The fiber optic probe (FOP) is developed to measure the shock-wave velocity and/or the detonation velocity inside an explosive. The space resolution can be as small as 0.5 mm. Single fibers are used as velocity pins, and as devices to measure the flatness of flyers. Arrays of fibers are used to measure the curvature of a shock or detonation front. Also a Fabry-Perot velocity Interferometer System is constructed to measure the velocity of the flyer of an electric gun and the particle velocity in a shock wave. It is possible to combine these two measurements to determine simultaneously the flyer velocity that induces a shock wave in sample and the particle velocity in a window material at the back in a single streak record.

Recent results of observation of three-dimensional (3-D) unsteady shockwave reflections are presented. The experiments are carried out using a diaphragmless shock tube in which shock waves are produced by a quickly opening piston valve which separates a high pressure driver gas from a low pressure test gas. This mechanism allows to create shock waves with a higher degree of repeatability than those obtained by conventional shock tubes in which shock waves are generated by rupturing diaphragms. Double exposure diffuse holographic interferometry is used for optical visualization. Instead of using diffusive object beams, collimated object beams are diffused by their reflection from the shock tube wall and the model painted with fluorescent paint. In addition, the time interval between two exposures is set to about 1 microsecond. Hence 3-D shock wave patterns are clearly observable. The experiment is supplemented by numerical visualizations using a 3-D adaptive unstructured Euler code working on the Cray C- 90 supercomputer platform, and then EnSight postprocessor is used to create numerical images. Two cases are examined: shock wave reflection from an inclined cylinder, and shock wave interaction with corner formed by the intersection of to wedges at 90 degree.

The detonic people know that the detonation waves need some minimum radius to turn the detonation direction for 90 degrees and much more to come from a forward detonation in a rearward detonation or retonation. Most of the corresponding tests can distinguish between the build-up distance and the necessary minimum radius. The retonation behavior is generally tested with tubular charges where the minimum wall thickness is determined at which a forward detonation converts also into a retonation. A new method with the help of multiple flash gap technique was tried in which the corner turning distance and the retonation behavior or the necessary minimum explosive layer thickness should be defined with 'one' test only.

Precursor air shocks (PAS), which have velocities in excess to the detonation velocities, are generated in slits of high explosive (HE) charges arranged parallel or under an angle of less than 60 degrees to the detonation wave. They are arriving earlier on the end surface of the high explosive charges because the gases expand fastly in radial directions and therefore optically cover the HE surface. Therefore the later arriving detonation front can be observed no longer. But by directly covering the end surface of the HE charge with a transparent medium -- plexiglass -- with slits corresponding to the explosive charge slits, the radial expansion of the PAS's can be delayed so long that the detonation wave profile can be observed on the HE surface. With this 'trick' interesting detonation behavior aspects were found in connection with slits oriented parallel or with small angles to the detonation direction. The used test setups will be described in detail with typical test results and their analyses.

The shaped charge jet diagnostic with the so-called synchro- streak-technique (SST) is well described in a number of earlier publications. New insights in the particularized jet behavior have been found with the observation of the jet with 'two' cameras in synchro streak technique in medium and larger distances. The test set-ups with the used two cameras, the gained streak records and their analysis will be described in detail. Some time has to be invested to get a good comparison of the discrete particles recorded at shorter distances or earlier times to the same particles observed at larger distances or later times, a comparison which can be also quickly and well understood by non specialists. These streak records with the corresponding analysis explain the high cut- off velocities of the jets in larger stand-offs and give clear indications on what has to be improved to obtain better qualities.

Studying the explosion control methodology related issues the author got interested in the possible influence of the external force fields on the initial symmetry in the process of substance convergence and scatter under powerful explosion. From this standpoint the paper analyzes the previous published results on the laboratory experimental investigation into the head-on collision of two similar bunches of tungsten particles with the relative velocity equal to 48 km/sec.

Paper demonstrates dynamic observation of the interaction of a shock wave with a vortex in a confined space by an animated display of sequential holographic interferograms. In conventional flow visualization methods, high speed photogrametry is a useful tool to observe high speed flows but its spatial resolution is somewhat limited. Holographic interferometry, on the contrary, can produce image information with a very high spatial resolution but only provides those at a specified time instant. In order to secure a dynamic display of shock wave phenomena, sequential interferograms must be taken successively at a given delay time in a shock tube which has a higher degree of repeatability. Experiments were conducted in a 60 mm X 150 mm shock tube at shock Mach number of 1.2 in air. Double exposure holographic interferograms were taken at every 5 microsecond time delay and a series of more than 30 interferograms was sequentially re-arranged on a computer so as to animate the interferograms. The animated result was then compared with a numerical simulation using a finite difference method with shock adaptive unstructured grids.

The first part of the work descried here deals with the metrology of image reducer systems like fiber optic tapers and relay lenses. These components are very useful to adapt the image on the phosphor screen of a streak camera on a limited size CCD array. We measured the collimated and lambertian transmissions, geometric distortions and the Modulation Transfer Function (MTF) of two SCHOTT tapers and of a specific VANNIER relay lens. The second part of this paper is related to a space-time distortions measurement of a nanosecond streak camera with an appropriate CCD readout system (THOMSON TSN506N). A correction method based on two 2D polynomials calculation was also tested. If some experimental conditions are verified, this method could be very efficient and useful when a streak camera is used as a multichannel chronometer (with a fiber optic adapter).

The Los Alamos National Laboratory in support of Department of Energy and Department of Defense projects is developing a continuous recording, intensified, CCD camera system having a high-frame rate and fast shutter capability. The camera frame rates can range from 1 to approximately 3500 frames per second with sub-nanosecond shuttering capability. Camera shuttering (or gating) is provided by a microchannel plate image intensifier employing a Los Alamos designed stripline geometry that incorporates impedance matching to reduce pulse reflections and dispersion. The CCD pixel array size is 512 X 512, which provides good-resolution over a relatively wide field of view. Video data readout from the CCD is through 16 parallel ports with a pixel rate of up to 75 Mpixels/s per port. Camera outputs include 16 ports of both analog video and digital video provided by 10-bit onboard digitizers. A computer controlled frame grabber is being fabricated which will record data from the digital outputs and store the data in a local memory for transfer into a non-volatile storage medium such as a removable disk drive. Salient characteristics and performance data of a prototype camera are presented and range gated imaging applications are discussed.

The flash-free high-speed video stroboscope for periodic and non-periodic repetitive events presented at the 22^th ICHSPP has been improved. All components of the system (the camera, frame grabber, digital phase shifter, frequency synthesizer and the universal counter) are now controlled by integrated software. The flexibility of the system has been increased by adding a number of features which can be selected and adjusted by the user. For easy documentation each of the captured and stored frames is labelled with the most important parameters of the investigated object as well as the settings of the stroboscope system and the date and time. The parameters are displayed on the screen during the observation of the object and during the recording and play back of the stored pictures and sequences. Unsteady objects, i.e. having a temporal/phase jitter or/and spatial fluctuations can be now investigated using the real-time frame averaging routines newly added to the software. Some system application examples and results are presented.

An improved design is presented for an ISIS, In-situ Storage Image Sensor, previously proposed by the authors for a high frame rate video camera of 1,000,000 pps. CCD channels of the sensor play dual roles for signal storage in an image capturing phase and for signal transfer in a read-out phase, which minimizes unutilized spaces on the light receptive area. The transfer direction is only vertical, which simplifies the structure of the sensor and provides better quality in reproduced images. An overwriting mechanism is built in, which facilitates synchronization of cease of the image capturing phase to the occurrence of a target event. The design is improved by coupling adjacent two CCD channels and two photodiodes, which provides wider spaces to place metal wires to increase rate of charge drive.

High speed imaging systems have been used in a large field of science and engineering. Although the high speed camera systems have been improved to high performance, most of their applications are only to get high speed motion pictures. However, in some fields of science and technology, it is useful to get some other information, such as temperature of combustion flame, thermal plasma and molten materials. Recent digital high speed video imaging technology should be able to get such information from those objects. For this purpose, we have already developed a high speed video camera system with three-intensified-sensors and cubic prism image splitter. The maximum frame rate is 40,500 pps (picture per second) at 64 X 64 pixels and 4,500 pps at 256 X 256 pixels with 256 (8 bit) intensity resolution for each pixel. The camera system can store more than 1,000 pictures continuously in solid state memory. In order to get the precise color images from this camera system, we need to develop a digital technique, which consists of a computer program and ancillary instruments, to adjust displacement of images taken from two or three image sensors and to calibrate relationship between incident light intensity and corresponding digital output signals. In this paper, the digital technique for pixel-based displacement adjustment are proposed. Although the displacement of the corresponding circle was more than 8 pixels in original image, the displacement was adjusted within 0.2 pixels at most by this method.

A new motion analysis system has been developed for the data reading of the film obtained from the applications of high speed photography. The system is composed of a step-motor driven high accuracy film transportation part, a data matrix readout subsystem employing CCD image processing technique, a high accuracy transparent electromagnetic digitizer, and a microcomputer with all the software packages of data reading, image catching and processing and object movement analyzing included.

For many years 16 mm film cameras have been used in severe environments. These film cameras are used on Hy-G automotive sleds, airborne weapon testing, range tracking, and other hazardous environments. The companies and government agencies using these cameras are in need of replacing them with a more cost-effective solution. Film-based cameras still produce the best resolving capability. However, film development time, chemical disposal, non-optimal lighting conditions, recurring media cost, and faster digital analysis are factors influencing the desire for a 16 mm film camera replacement. This paper will describe a new imager from Kodak that has been designed to replace 16 mm high-speed film cameras. Also included is a detailed configuration, operational scenario, and cost analysis of Kodak's imager for airborne applications. The KODAK EKTAPRO HG Imager, Model 2000 is a high-resolution color or monochrome CCD Camera especially designed for replacement of rugged high-speed film cameras. The HG Imager is a self-contained camera. It features a high-resolution [512 X 384], light-sensitive CCD sensor with an electronic shutter. This shutter provides blooming protection that prevents 'smearing' of bright light sources, e.g., camera looking into a bright sun reflection. The HG Imager is a very rugged camera packaged in a highly integrated housing. This imager operates from +22 to 42 VDC. The HG Imager has a similar interface and form factor as that of high-speed film cameras, e.g., Photosonics 1B. However, the HG also has the digital interfaces such as 100-Base-T Ethernet and RS-485 that enable control and image transfer. The HG Imager is designed to replace 16 mm film cameras that support rugged testing applications.

The present article summarizes results of the authors' attempts to improve technical/maintenance characteristics of a computer CCD system for monitoring events and create technologically feasible commercial system samples meeting most demands for high resolution monitoring of fast processes producing weak luminous effects.

The C(Pi) M11 x-ray sensitive device is intended for recording the one-dimensional space distribution of x-radiation fluence in the spectral energy range from 0.2 to 40.0 keV and can be used as a part of x-ray spectrometers of different types instead of the photographic film and for measurement of spatial parameters of x-ray beams and oth.

Model MD-1 CCD Micro High-speed Videography System recently developed in Zhejiang University endeavors to apply high speed strobe videography method to micro domain. Computer controlled high speed Xenon pulses are flashed to illuminate moving micro objects. Image sequences of the moving micro objects are recorded in one frame by a CCD video camera and transferred to the computer to be reviewed, processed and stored. The system is characterized by the ability to analyze object dynamics of micrometer level with the highest magnification rate of 15,000 times, the highest 'freezing' ability of several microseconds and the highest image capture frequency of 33,000 IPS (images per second). Principles, hardware and software compositions and applications of the system are illustrated in this paper as well as the multi-beam condenser, a specially designed micro illumination device to obtain a uniform, well-balanced bright field in experiments.

In this paper, image segmentation technique using color information was introduced to extract bullet region and finally obtain bullet motion parameters. This method differs from previous processing method with gray information. Utilizing color hue component difference to extract every bullet region and using morphological operation to smooth edge of regions are two main processes of this method. Edge of bullet region is finally traced with Freeman chaincode. Chaincode is used to recognize regions and used in following neutral axis fitting. Velocity and acceleration of bullet can be obtained when the gravity center of each bullet region is achieved. Least Square Method is used to fit neutral axis of bullet image with contour data, accordingly the elevation angle of bullet at each moment can be got.

Digitization processing system for photoelectric tracing image, that is mainly made of the video interpretoscope sub- system and the sampling and processing data sub-system, is used for the data statistics analysis and detection of tracing precision and tracing performance of the photoelectric tracing device while tracing the air targets. When real-time automatically measured by video signal, the precision of deviation between air target and the optical axle of photoelectric tracing device is 0.05 mrd, the processing time less than or equal to 20 ms. And more than twenty targets can be half-automatically measured by video signals.

Many fast events are three dimensional but the normal high- speed cameras are only suitable for 2-D images. Therefore it was investigated which stereoscopic methods could be used to study three dimensional processes. The choice of the optimal method is dependent on the investigated event. To record the 3-D spreading of an injection jet in a laboratory has to use other methods as to record an explosion from a smoke bomb in open air. Three methods are described and critically compared. Furthermore it is shown how from films with double pictures a cinematographic film can be made.

New class of nonlinear filters called Vector Median Rational Hybrid Filters (VMRHF) for multispectral image processing was introduced and applied to color image filtering problem. These filters are based on Rational Functions (RF). There are several advantages to the use of this function. First, it is a universal approximator and a good extrapolator. Second, it can be trained by a linear adaptive algorithm. Third, it has a best approximation for a specified function. The output is the result of vector rational operation taking into account three sub-functions, such as two vector median (VM) sub- filters and one center weighted vector median filter (CWVMF). It was shown that every sub-function will preserve details within its sub-window. These filters exhibit desirable properties, such as, edge and details preservation and accurate chromaticity estimation. The performance of the proposed filter is compared against widely known nonlinear filters for multispectral image processing such as: Vector median filters (VMF) introduced by Astola et al, which are derived as maximum likelihood (ML) estimates from exponential distributions, the class of directional-distance filters (DDF) introduced to study the processing of color image data using directional information. Experimental and comparative results in color image filtering show very good performance measures when the error is measured in the L*a*b* space. L*a*b* is know as a space where equal color differences result in equal distances, and therefore, it is close to the human perception of colors.

A biometric access control system based on identification of human face is presented. The system developed performs remote measurements of the necessary face features. Two different scenarios of the system behavior are implemented. The first one assumes the verification of personal data entered by visitor from console using keyboard or card reader. The system functions as an automatic checkpoint, that strictly controls access of different visitors. The other scenario makes it possible to identify visitors without any person identifier or pass. Only person biometrics are used to identify the visitor. The recognition system automatically finds necessary identification information preliminary stored in the database. Two laboratory models of recognition system were developed. The models are designed to use different information types and sources. In addition to stereoscopic images inputted to computer from cameras the models can use voice data and some person physical characteristics such as person's height, measured by imaging system.

Development of computer vision systems raises a problem of creating effective methods for restoring surface characteristics from their photographic images minimizing calculations while preserving reasonable accuracy of measurements. Here optimized algorithms of the surface reconstruction from stereo-images is proposed. The optimization is achieved by introducing some constraints on the conditions of image recording and by involving an a priory affirmation about objects in study. Effective algorithms have been developed on the basis of correlation method estimating corresponding points on images in stereo set and disparity map computation. Performance optimization is achieved by some modifications of correlation method including a pyramidal presentation of the images. The system uses a stereoscopic registration of face images and performs real-time image processing. The system was tested on a database of stereo- images.

Work presented suggests a combined informational space and decision rule for recognition of 3-D objects. The informational space consists of heterogeneous sets of features (i.e. belonging to different spaces), that are object images, images of certain object features and 3-D object surface representation. Decision rule for recognition in this combined space is proposed. The method was tested on a database of human face stereo-images and gave a significant improvement of reliability of automatic recognition system.

Some general problems of multichannel processing of images rarely considered in the publications is discussed: alternative methods of a joint correlation signals postprocessing and appropriate definitions of a signal/noise criterion, arrangement of optical filters bank on the physical carrier, representation of filters at computer synthesis.

This paper describes a novel idea of image analysis method of pulse laser in-line hologram of particles to obtain information on particle diameter. Present method is based on the following property of the hologram. Fringe interval of the hologram decreases with radius, and the corresponding spatial frequency increases with radius. Fourier transformed pattern of the hologram, therefore, has the similar properties. We have proposed here the use of this FFT pattern of the hologram for the image analysis. It is shown that the FFT pattern has a white ring zone, which corresponds to the zero-point of the envelope function of original fringe pattern. It is demonstrated that measurement of the diameter of this ring gives a reliable way of obtaining particle diameter. Feasibility of the method has been shown by numerical experiment for Fraunhofer and Fresnel hologram.

Since the moment of laser appearance and till now the attention concentrated on great potentiality realization of coherent optical data processing systems. However, the difficulties occurred in creating the workable systems of this type were the reasons of spreading the field of investigation on diffraction systems in which not only the coherent, but the partially coherent and non-coherent illumination is used. Spatial coherence and light spectrum components as well as amplitude, phase and polarization of light passed through the optical system can be modulated by the information to be processed. The transformation of spatial coherence allows to perform Fourier and correlation analysis of images or temporal signals formed by spatially incoherent quasimonochromatic light, when the traditional holographic matched filter is used. The input of two-dimensional data arrays can be performed by the acousto-optic deflector. Developed method of bipolar holographic filter pulse response synthesis increases image recognition reliability. If the light is non- monochromatic it is possible to involve the spectral components as the information parameters in correlation signal formation due to the special modulating mask placed in reference beam when the filter is recorded. A possibility of optical system creation with no lens for image formation based on spatial coherence transform is considered.

In this work we theoretically investigated the peculiarities of dynamics of hologram recording in photopolymer medium by short light pulses which space profiles are limited in two dimensions.The analytical model of dynamics of record is based on the equations Lorentz-Lorenz and relations of the radical photopolymerization theory. In the stage of readout the mathematical model have been considered as parametrical processes relatively time variable and involved the equations of light diffraction on holographic gratings with taking into account the diffraction effects connected with free propagation of light beams. The numerical simulation results of dynamics of holographic gratings recording and its readout by Gaussian light beams at various meanings of mathematical model parameters are presented.

High speed imaging techniques can provide the researcher with an understanding of the physical processes that result from ballistic impacts. A single high resolution image can be useful, however, to offer significant advantages a camera must record sequential images of the event detailing the interaction between projectile and target. To take full advantage of the visualization process the recorded image sequence must be temporally and geometrically accurate to facilitate meaningful analysis. The Imacon 468 will contribute to the researcher's aims, by capturing accurately detailed records of the event in both time and space.

Streak camera based on two-stage streak image tube with 40 X 4 mm² S-20 photocathode of the approximately 30 image compression factor for LIDAR Thomson scattering diagnostics has been developed, constructed and tested. Over 300 time resolved 60 ps elements at 10 dots of spatial resolution has been obtained. Results of the streak camera testing are presented and discussed.

The paper describes principle of operation and main technical data of CP(Gamma) 7, CP(Gamma) 8 and CP(Gamma) 9 broadband analog and digital recorders which are intended for combined analog and digital recording of single and low-repetition signals of pico- nano- microsecond duration on the screen of a storage oscilloscope CRT with a microchannel plate of image intensifier (CRT with MCP) in the 0 to 10 GHz frequency range. This permits to consider them as instruments combining in themselves the functions of a broadband analog and digital storage oscilloscope with superfast response at maximum sampling rate up to 256 - 512 GHz.

This paper presents the results of development of X-ray streak cameras, calibration test beds and methods for calibration of streak cameras and elements of X-ray optical schemes, procedures for recording a number of plasma parameters. We describe methods for streak photography of laser-produced plasma X-ray emission in experiments with various targets conducted on the facilities ISKRA-4 and ISKRA-5. These methods allow to make time-resolved records of the continuous plasma X-ray emission in various spectral ranges, to sweep in time line X-ray emission, to make simultaneous records of several plasma images in various spectral ranges, to make simultaneous records of several cross-sections of an object with subsequent reconstruction of a number of its two-dimensional images at various moments of time with ps time resolution. By using these methods it is possible to control target irradiation uniformity in time, to study the dynamics of the microsphere implosion and outwardly blowing plasma corona, to determine the lifetime of the imploded core, to investigate the time evolution of electron temperature and to study the mixing processes of materials of various densities in multilayered targets.

Modern developments of the RIPT for investigation of radiation characteristics in fast processes (in the nano- and subnanosecond range) are presented. These are semiconductor detectors based on new materials) for soft X-ray radiation, multichannel vacuum X-ray detectors, electron-optical image converters and recorders, optical and X-ray frame and streak cameras based on new materials. Analog and digital recorders (10 GHz), digital TV-recorders for X-ray radiation using CCD- arrays. Digital time interval measuring devices, analog and digital converters and other recorders. Radiation generators and calibration stands for metrological certification of X-ray detectors and recorders.

The analysis of modern state of the oscillography methods of high-speed single-shot pulse signals is given. The problems of oscilloscope graphic registration pulse single-shot of millivolt nano- and picosecond duration are described. The author suggests methods of realization and creation of the two ways of wide-band oscillographic installation, working in the real-time. The first way is based on universal oscillographs to register and measure millivolt single-shot pulses in the frequency band up to 1 GHz. The second way is high-speed oscillography, for the investigation of single-shot pulses with the amplitude of signals in the frequency range 0 divided by 7,5 GHz. The prospects of the oscillographic method of registration were shown in a physical experiment.

The chronography camera providing the radiation spectra dynamics recording over the wave length range 220 - 750 nm for radiation pulses durations from 3 ps to 1 microsecond(s) was created for measurements in spectroscopy field and laser diagnostics. The camera is being controlled by IBM computer including sweep ranges switching and monitor output of measuring information data also.

As before the triggered vacuum gaps (TVG) are used in high- speed photography and in devices for illumination of high- speed processes by pulses of optical and X-rays. So the problem of improvement of their reliability and lifetime still remains.

The principle of operation, the design, as well as parameters and characteristics of streak and frame image converters and cameras designed at the Research Institute of Pulse Technique (RIPT) for investigation of soft X-rays are described.

In laser isotope separation experiments a high-speed IR recording camera ITMGT has been used. With the help of this camera we were first to realize photographic recording of the spatiotemporal radiation structure in the chemical reactor located inside the resonator of a high-power CO₂ laser. The obtained photographs reveal spatial nonuniformity of the radiation structure and self-focusing of laser radiation inside the resonator. Owing to the obtained information it has become possible to study the physics of self-focusing initiation in media with nonlinear absorption of IR radiation and this information will be useful for optimization of the processes of isotope enrichment by CO₂ laser radiation.

A procedure is described that can be used to reconstruct the quantum state of a molecular ensemble from time-averaged position probability density functions determined by time- resolved electron diffraction (TRED). The procedure makes use of established techniques for evaluating the density matrix and the phase space joint probability density; i.e., the Wigner function. A novel expression for describing electron diffraction intensities in terms of the Wigner function is presented. An approximate variant of the method, neglecting the off-diagonal elements of the density matrix, was tested by analyzing gas electron diffraction data for N₂ in a Boltzmann distribution, and TRED data obtained from the 193 nm photodissociation of CS₂ to carbon monosulfide, CS, at 20, 40, and 120 ns after irradiation. Although the diagonal density matrix elements do not define completely the quantum state of a system, nonetheless, the approximate Wigner functions derived from them display the expected features of a Gaussian-like function in the case of N₂; and, in the case of CS, they are in agreement with other investigations, indicating collision-less vibrational energy transfer mechanisms for nascent CS during the first 20 ns, and collision-induced electronic S(¹D_J) to vibrational CS(X¹(Sigma) _g⁺) energy transfer.

After a brief overview of time-resolved electron diffraction experiments on a nanosecond time scale, more recent instrumental improvements are described which successfully extend the time resolution of the apparatus to the picosecond regime. Modifications described include a new sample inlet system, intensified detector, and electron pulse generation laser. Taken together, they have led to significant improvements in both signal level and ultimate time resolution; an upper estimate of the electron pulse width is approximately 20 ps. Enhancements are such that, for operation in the nanosecond time domain, an entire diffraction pattern over a useful range of scattering angles may be collected from a gas-phase sample in a single electron pulse.

A review of time-resolved reflection high-energy electron diffraction studies of approximately 100-ps laser heated surfaces is given. The dynamic structural behavior is shown to be strongly dependent on surface orientation and is different from that observed under slow heating conditions. Surface superheating and melting of single crystals of lead are described in addition to surface reconstruction of germanium.

The radiographic characteristics of a high-intensity kilohertz-range stroboscopic x-ray generator (SX-C98) are described. This generator consists of the following major components: a controller, a condenser unit having a Cockcroft circuit, and an x-ray tube unit in conjunction with a grid controller. The main condenser of about 500 nF in the unit is charged up to 100 kV by the circuit, and the electric charges in the condenser are discharged to the triode by the grid controller. Although the tube voltage slightly decreased during the discharging for generating x-rays, the maximum value was equivalent to the initial charging voltage of the main condenser. The maximum values of the tube current and the repetition rate were about 0.5 A and 32 kHz, respectively. The pulse width of the x-rays ranged from approximately 0.01 to 1.0 ms, and the maximum shot number had a value of 32. At a constant filament (cathode) temperature, the x-ray intensity increased according to increases in the charging voltage and to increases in the duration, and the intensity with a duration of about Ims and a charging voltage of 70 kV was 140 nC/kg at 1.0 m per pulse. When the charging voltage was increased, the dimension of the focal spot slightly increased, and the maximum values were about 3.5 X 3.5 mm.

Various characteristics of a plasma flash x-ray generator having a cold-cathode radiation tube and its application to high-speed soft radiography are described. The x-ray generator employs a high-voltage power supply, a low-impedance coaxial transmission line with a gap switch, a high-voltage condenser with a capacity of about 200 nF, a turbo-molecular pump, a thyristor pulser as a trigger device, and a flash x-ray tube. The high-voltage main condenser is charged up to 60 kV by the power supply, and the electric charges in the condenser are discharged to the tube after triggering the cathode electrode. The flash x-rays are then produced. The x-ray tube is of a demountable triode which is connected to the turbo molecular pump with a pressure of approximately 1 mPa. As the electron flows from the cathode electrode are roughly converged to the target by the electric field in the tube, the plasma x-ray source which consists of metal ions and electrons is produced by the target evaporating. Both the tube voltage and current displayed damped oscillations, and their peak values increased according to increases in the charging voltage. In the present work, the peak tube voltage was almost equivalent to the initial charging voltage of the main condenser, and the peak current was less than 30 kA. In this experiment, we employed four types of plasma targets as follows: (1) single target, (2) coaxial double target, (3) alloy target, and (4) plate target. When the single target in conjunction with the monochromatic filter was employed, high-intensity quasi- monochromatic x-rays were obtained. Next, the characteristic x-ray intensities from the outer target increased in the case where the double target was used. By using the alloy (copper tungsten) target, the x-ray intensities of the copper K-series lines increased. Finally, when the linear plasma x-ray source was formed by using the plate target, the bremsstrahlung x- rays were absorbed and were converted into florescent rays, and high-intensity characteristic x-rays were produced.

The fundamental study on a flash water-window x-ray generator (WFX-98) is described. This generator is composed of a high- voltage power supply, a polarity-inversion ignitron pulser, an oil-diffusion pump, and a radiation tube with a capillary. The high-voltage condenser of about 0.2 (mu) F in the pulser is charged up to 20 kV by the power supply, and the electric charges in the condenser are discharged to the capillary in the tube after closing the ignitron. In the present work, the chamber is evacuated by the pump with a pressure of about 1 mPa, and the titanium anode and cathode electrodes are employed to produce L-series characteristic x-rays in the water-window range. The diameter and the length of the ferrite capillary are 2.0 and 29 mm, respectively. Both the cathode voltage and the discharge current displayed damped oscillations. The peak values of the voltage and current increased when the charging voltage was increased, and their maximum values were -11 kV and 3.8 kA, respectively.

The constructions and the characteristics of a transformer- driven stroboscopic x-ray generator (SX-T98) are described. This generator is primarily designed in order to increase the maximum photon energy of the pulsed x-rays and is composed of the following essential components: a thyratron pulser, a high-voltage transformer having a ferrite core with a maximum output voltage of 300 kV, a sequence controller, a DC power supply for the hot cathode (filament), and an x-ray tube. The main condenser of 24 nF in the pulser is charged up to 14 kV, and the electric charges in the condenser are discharged repetitively to the primary coil of the transformer. Because the high-voltage pulses from the secondary coil are then applied to the x-ray tube, repetitive harder x-rays are produced. The x-ray tube is of a triode having a hot-cathode which is primarily driven at the temperature-limited current region In this triode, because the grid is connected to the cathode, this tube is driven as a diode. The tube voltage roughly increased in proportion to the charging voltage, and the maximum value was about 300 kV. Thus, the maximum photon energy had a value of about 300 keV. The tube current was primarily determined by the filament temperature and had values of less than 2 A. The x-ray output displayed plural pulses, and the pulse width of the first pulse was about 300 ns. The maximum repetition rate was about 1 kHz, and the dimension of the x-ray source had values of 3.5 X 3.5 mm.

By the pulse X-ray diffractometry method the interaction process of the plates, accelerated by the charge of explosive up to velocities in the range from 1.5 to 5 km/s, with the cylindrical and plane indenters was investigated. For obtaining rather a high spatial resolution and the X-ray diffraction contrast the pulse X-ray apparatus with the 1 MV generator and the recording system based on fine-grained fluorescent screens has been used. In experiments the process registration in the mutually perpendicular directions has been performed. This makes possible to register the plates moving along the axis of exposure as well as perpendicularly to it and to investigate some interesting processes, namely: the interaction of indenters having small cross-section sizes, the motion instability of plates made of low-strength materials, the brittle failure of the plates in the zone of the lateral load action.

Dense Plasma Focus (DPF) of a compact performance is proposed as a powerful X-ray source for various applications. The general property of DPF X-ray pulse is its short duration (t approximately 10 ns). DPF X-ray spectrum reached from zero to a few hundred kilo electron volts. Hard X-ray radiation (E equals 20 ... 100 keV) generated by the DPF device with energy storage about 3 kJ makes it possible to have an X-ray photo of any fast movable object for example rotating car wheel tire. A pulse hard X-ray radiation also can be used in the dynamic flaw detection. The combination of the pulse, energy, and spectral parameters of a DPF hard X-ray radiation allow to consider DPF as a device free from a competition for mentioned applications. A DPF soft X-ray emission (9 ... 14 Angstrom) can be used for X-ray lithography. This DPF application as well as mentioned above are tested experimentally with a success. Besides we have a plan to apply a DPF soft X-ray radiation for the diagnosis of a fast hot dense plasma process by means of radiography of another DPF during its action.

The article presents technical characteristics of FER-14 image converter streak camera that can register pattern of electric discharge formation in long air gaps with all possible parameters variations of the process. The main results that were obtained with the camera are listed in this article.

The scheme of the linear accelerator with repeated use of an accelerating system is considered at the expense of a reflection of electrons from magnetic mirrors located on both sides of a waveguide. The field of a mirror consists of a trap field a and spiral magnetic field. Dynamics of particles in such a field with different energy values was investigated by the numerical method.

A target diagnostic procedure is described using the results from ps time-resolved recording of line and continuous X-ray emission in ISKRA-4 experiments on investigation of thin layer mixing processes during laser acceleration of plane multi- layered targets made of materials with dissimilar densities.

A possibility of registration of fast ions (protons, alpha- particles) with the help of an X-ray streak camera is demonstrated. The spatial resolution of the device is 50 micrometer, the physical time resolution with the use of a CsJ-cathode is 7 ps. From (alpha) -emission a secondary electrons yield is determined of (eta) equals 8 el../part. The device sensitivity makes it possible to register separate (alpha) -particles and protons. On the basis of the device there have been elaborated techniques of spatial-spectral registering of radiation of fast ions emitted by laser thermonuclear targets. The techniques are destined to study processes of interaction of high-intensive laser radiation with an appliance Iskra-5 target.

The time sweep by the optical streak camera of large number of plasma column sections is carried out. This allows to receive the 2-dimensional images with time of an exposition up to 0.5 ns, frequency of shooting up to 1 GHz and number of the frames up to 10². The technique is intended for study of dynamics of a plasma pinch behavior and allows to determine its configuration, characteristics sizes, dynamics of occurrence and localization of instabilities, speed of the expansion and compression, dynamics of temperature change. The ways of resolution increase are discussed.

In work the formulas for calculation of the amplitude-time characteristics of a Cherenkov fiber-optic ionizing radiation sensor are given. The results of the mathematical modeling which has been carried out on these formulas, coincide qualitatively with experimental data.

This thesis uses Monte Carlo method to numerically simulate the course of electron and photon transportion. We have Computed and analyzed the image which is formed at film when high energy X-ray irradiates dense object. It analyzes two kinds of calumniators. We have analyzed influences which result from the front and back window. We have got the object attenuation factor of exposure from X-ray source to film, have gained space distribution of exposure at film and have gained that every element contributes to scattered radiation.

The results of the experiments at the installation 'PICO' with thin foils heating by laser radiation pulses of nanosecond duration are reported. The Al foils with thickness in the range from 3 (mu) up to 40 (mu) where used as a targets. The flux density was varied from 10¹³ W/cm² to 10¹⁴ W/cm². The sharp dependence of the portion of laser energy passed through the target on foil thickness was observed. This phenomena was accompanied by relatively small decrease of the passed radiation pulse duration. The anomalously high speed burning through of thin foil was observed in these experiments and the conclusion on possible mechanism of this phenomena has been done on the base of comparison of experimental data with theoretical calculations. The observed phenomena can be interpreted on the base of conjecture about the local burning through of a target in the small areas at the target surface with much more values of flux density than average one and following laser radiation self-focusing and formation of 'hot spots.'

In this paper, we report the diode pumped femtosecond Cr:LiSAF laser. Through numerical analysis on the astigmatism, a folded three-mirror cavity is designed. Then we investigate its CW and mode locking operation. When it is pumped by the pulse, the output laser with time duration less than 100 fs is obtained.

Original laboratory built optoelectronic control system for near IR lasers was applied for a pulsed Nd:glass laser. Optoelectronic control system was based on a high-voltage silicon structures (applied voltage greater than or equal to 3 kV, response time less than 0.5 ns). Self-mode-locking was achieved with aid of an optoelectronic control system only (without any saturable absorber). Passive mode-locking peculiarities of the Nd:glass laser with dye 3274U solution in ethanol as a saturable absorber were investigated. Subnanosecond response time of the optoelectronic system allowed us to realize three operating regimes of the laser, which are distinguished by the temporal delay of the negative feedback system.

The single shot autocorrelator designed to measure the AF of the ultrashort laser pulses in the temporal range of 30 - 200 fs and in spectral range 730 - 820 nm is described.

In chirped pulse amplification system pulse stretching is an important part. To investigate the behavior of an eight-pass single grating pulse stretcher, we examine in two steps: firstly an unchirped ultrashort pulse goes first four-pass through the stretcher, it will be broadened in pulsewidth and provided with amount of positive chirps. Secondly this chirped pulse will has another four-pass experience through the stretcher. Followed by our close calculations, it is clear that stretching factor in the second part is almost 2, and the total stretching factor of this system is equal to the multiplication of the two factors.

In this paper we reported the shortest pulse duration, to our knowledge, from Ti:Sapphire laser in the low gain region. Pumped by 14.5 W from the all-line of Argon-ion laser, a stable laser pulse train centered at 0.94 micrometer, with pulse duration of 37 fs, bandwidth of 33 nm, average power of 80 mW, and a tuning range from 0.9 micrometer to 0.976 micrometer has been obtained.

The industrial high-stable picosecond solid-state laser 'Luch- 2' on AYG:Nd³⁺ is created for operation in precise distance measurement field. The feature of this one realized by means of optical scheme choice are: (1) stability of radiation pulses energy and duration parameters from pulse to pulse when lasting operation takes place is no less than 3%; (2) possibility of operation in environment temperature range from +5 to +40 degrees Celsius without additional positioning; (3) laser operation control possibility by means of computer.

The possibility of the amplification of image brightness by active medium of the photodissociative iodine laser (PIL) have been shown. Brightness of the image grating with grid stroke of 10 mm^-1 was amplified in 50 times at mono impulse lasing action and in 10* at free-running one. Contrast of amplified image as equal 0.8 in both occasions.

Moderate feedback levels in edge emitting semiconductor lasers may cause different unstable regimes of operation. One of them is known as the regime of Low Frequency Fluctuations. We performed an experimental study of this regime on a picosecond time scale using a single-shot streak camera. Our measurements show the fine temporal structure of the laser emission in this regime and reveal the multimode nature of laser operation.

We present the results of steady state and time dependent photoluminescence measurements on ZnSe/Zn_0.83Cd_0.17Se multiple quantum wells from which the dominant recombination mechanisms are identified. Our experiments show that excitons rather than free carriers are the players in the recombination dynamics. Exciton localization is found to be an important factor competing with nonradiative recombination and enhancing the radiative efficiency in the multiple quantum wells investigated.

Simple improvement of the control system in the laser controlled by fast time-shifted negative feedback allow us to obtain essentially shorter optical pulses in mode-locking regime. Mathematical model was developed, computer simulation was performed. We also have experimentally demonstrated two times pulse shortening as a result of HF electric oscillations self-excitation in the control system. Control system unit with resonant frequency approximately 1 GHz based on high- voltage silicon mesostructure was created. This scheme was applied to Nd-YAG laser. Formation process and stable shape of the control voltage were studied. Fine time structure of the emitted light was investigated by use of the direct streak- camera method, minimum laser pulse duration was 70 plus or minus 15 ps.

We have used piezo-driven Fabry-Perot interferometers in the past for many continuous velocity-time measurements of fast moving surfaces. In order to avoid the annoying drift of some of these devices, we have developed and used inexpensive, solid glass, striped etalons with lengths up to 64 mm. Useable apertures are 35 mm by 80 mm with a finess of 25. A roundabout technique was devised for double cavity operation. We built a passive thermal housing for temperature stability, with tilt and height adjustments. We have also developed and used our first fixed etalon air-spaced cavity with a rotatable glass double-cavity insert. The rotation allows the referee cavity fractional order to be adjusted separately from that of the main cavity. It needs very little thermal protection, and eliminates the need for a roundabout scheme for double cavity operation, but is more costly than the solid glass version. For a cavity with an air length H, glass length T, index n and wavelength (lambda) , the fringe angles are (root)j(lambda) /(H+T/n) where j is the fractional order plus an integer. This means double cavity fringe patterns plotted vs. velocity will cross if both air and glass are part of the system. This crossing, which is an advantage, will not occur for pure glass or pure air systems. The velocity per fringe is given by c(lambda) /4[H+T(n- (lambda) dn/d(lambda) )] where dn/d(lambda) is the derivative of index with respect to wavelengths. This expression therefore includes the effects of dispersion in the glass. Because the angle depends upon T/n and the velocity upon Tn, there is no equivalent air cavity for a given glass cavity. Very high quality glass is preferable to air, since for a given velocity per fringe, the fringe separation is larger for glass cavities, resulting in less finess degradation due to streak camera spatial resolution.

A xenon multiple exposure light source device was manufactured to record the trajectory of a flying javelin, and a wind tunnel experiment was performed with some javelin models to analyze the flying characteristics of the javelin. Furthermore, form of javelin throwing by athletes was recorded to estimate the characteristics in the form of each athlete using a high speed cameras.

The methods and software of the fast-running processes' investigation in various media (solids, liquids, gas, plasma) and rocket-space engineering (RSE) technical objects were developed. The mathematical models of the objects under research were created in the conditions of exposure to the field possessing different physical nature. The hardware and programming complex of the film-phototelerecording and data processing combining the computer equipment, television- and film technique, was created, permitting to use the advantages of every type of the technical systems for the investigation of certain processes, objects and their characteristics. The hardware and programming complex of the film- phototelerecording and data processing is used both in the development and designing periods, and during tests, as well as under the long-term operation of technical objects in the ordinary and extremal situations. The fast-running processes' investigations in various media and RSE objects were performed, and by their results the data bank was made.

With the aim of technological process automatization and control for high-frequency welding of different diameters pipes the machine-program complex (APC) was designed. APC gives the opportunity to create the cine- and telerecording of process in production conditions at the mill '159 - 529' of Novomoskovsky Tube Rolling Mill (Ukraine). With the help of APC in real functioning mill conditions the character of flashing zone length changing and the angle of convergence depending on pipe welding speed was investigated, also the zone of jumpers is defined. The comparison of theoretical and experimental data gave an opportunity to define a welding rate which is optimal for the most qualitative values of welded joints in the range of pipe products of mill '159 - 529.'

Phenomenology of leader process of long spark was investigated with the help of ICC with internal intensifier. Fine structures of streamer zones were determined. Trend of their characteristics was done for sparks from 0.5 up to 100 m and voltage from 0.5 up to 5 MV. Characteristics were extrapolated on lightning using empirical models. Expected ICC pictures were done upward and downward lightning leaders. Ways of ICC use were discussed.

The article deals with questions of obtaining high-speed particles images and their recording by a holographic method. The proposed technique permits to obtain high-speed images of particles, having arbitrary shapes and sizes. In this case the particle image velocity is smoothly regulated in the wide range; the error in the velocity measurement does not exceed 0.2%.

In August of 1989, the Galileo spacecraft, consisting of an orbiter and probe, was mounted to an Inertial Upper Stage (IUS) rocket stage being readied for flight aboard NASA's Space Shuttle, 'STS-34,' 'Atlantis.' During routine age testing of an IUS igniter fire line circuit, a 'b-nut' failure occurred. On board the Galileo/IUS first stage rocket motor was a b-nut from this failed lot. There was concern that the mission could be jeopardized if the b-nut failed because of the close proximity of the IUS second stage rocket motor nozzle. A fix had to be made to insure mission success. Chemical Systems Division was called upon to provide high- speed motion picture photography at 3000 frames per second to analyze the dynamics of a b-nut failure, and verify that the fix would prevent damage to the second stage nozzle, should a b-nut failure occur. This report will show how displacement and velocity measurements can be made from 16 mm motion picture film.

The videogrammetry method is an improvement of a traditional photogrammetry method realized with the help of modern means of videoengineering, digital registration and image processing. The goal of the method is to restore the three- dimensional coordinates of a required point of an object under test on base of two coordinates of center of the point's image at the registration plane. One of the ways to resolve the arising uncertainty of restoration is to use of a structured illuminating beam of light rays; the known geometry of the beam helps to obtain the missing information. The special cases of such a beam are a light sheet and a beam of the parallel or radial light rays. The methods of videogrammetry with a laser light sheet and with a beam of radial light rays are both simultaneously applied in the measuring system to check the geometrical parameters of railway wheels which has been placed in operation on the industrial conveyor at Vyksunsky steel works. The measuring system uses three videogrammetric channels. Two of them are apply the laser light sheet scheme. These channels have identical features and are intended for measurements of geometry of the radial section fragments of the internal and external disk surfaces of the wheel. The channels have a measurement range of 500 X 500 mm. The measurement tolerance of each of the two coordinates do not exceed 0.15 mm. The third channel is constructed under a shadowgraphic scheme on base of a light beam of radial rays and provides the measurements of the wheel rolling surface geometry. This channel has a measurement range of 120 X 180 mm and measurement tolerance of 0.05 mm. The measuring system works in real time with the conveyor. A wheel tolerance check cycle, which takes 45 seconds includes lifting the wheel to the measurement position, rotating the wheel one full revolution with simultaneous measurement of a given number (up to 12) of radial sections, lowering the wheel to the conveyor line, processing and displaying the measurement results.

Complex of image converter equipment for identification and speed measurement of artificial meteorites-balls accelerated up to the circular velocity is described in the article.

This paper presents a real time method of radar plot detection. This algorithm is used in a radar tracking system. It is implemented with low cost FPGA and DSP. Its main advantages are simplicity and short latency.

Spectroscopic method was used to observe pulse laser induced ablation plume of graphite. Time-integrated emission spectrum of ablation plume of graphite was measured for laser wavelengths of 1064 nm, 532 nm and 308 nm. TOF measurements were also made to determine both the species of plume constituents and their velocity as they move from the target surface. By analyzing the obtained spectrum, several species were identified, i.e., at least a carbon ion, a carbon atom and a C₂ molecule. Dynamic vibrational temperature was estimated for the obtained spectra of swan bands based on the statistical mechanics. The ablation mechanisms were discussed considering the non-equilibrium nature of the plume.

The vibrodiagnostic of electronic engineering products, used in systems of automatic control of flying apparatus, to which quartz resonators concern, serves at improvement of optimum designs in a given range of working vibrations. The operation an onboard of a control system shows the increasing requirements not only to reliability and stability of their work, but also stability to vibrating and climatic influence. So, for example, many designs of quartz resonators should maintain vibrating overloads up to 5 g in a range from 5 Hz up to 10 kHz. The vibrodiagnostic and forecasting of reliability of quartz resonators for onboard a control system came true with the help of the holographic module, which consists of two blocks; the measuring block and block of data processing on the basis of the personal computer. The resonant frequencies, were defined by a method 'real-time,' the definition of overloads on the quartz resonator was conducted by a method 'real-time' and 'time-averaging.' Existing various optical methods of research of fluctuations did not allow to register longitudinal and planimetric styles of fluctuations whereas the vector of displacement is directed in parallel to a plane of a quartz piezoelement. A method of a holographic interferometry has allowed supervising not only transverse, but also longitudinal and planimetric styles of fluctuations of quartz resonators. Four patents of Russia protect the constructive elements of the developed complex holographic module. The given module was used for a vibrodiagnostic of quartz resonators in a range of own frequencies of fluctuation from 5 Hz up to 10 kHz with an overload up to 5 g, thus were eliminated constructive and technology factors, influencing on shift of own frequencies of quartz resonators in low-frequency area.

The vibrations of different modes and directions are set up in a quartz resonator piezoelectric element due to anisotropy; i.e. the quartz resonator is a system of infinite number of degrees of freedom. Such system may be considered as a monofrequent one only conditionally, so that connection of operating vibration and other vibration is sufficiently slight. Under excitation of quartz resonators the stress strains of various modes are set up at once due to elastic connections. The main vibrations and their harmonics correspond to those stress strains. Moreover, a system of standing waves of a definite frequency of natural vibrations is produced in piezoelectric elements of finite dimensions. Thus, apart from the main frequency, the quartz resonators have an inherence of definite spectrum of resonance frequencies of undesirable, various intensity vibrations expressed by the amplitude-frequency characteristic (AFC) of resonators. The propagation studies have shown that during acoustic wave movement in any anisotropic body an angle other that 0 or 90 exists between the wave front and the wave direction, i.e. the waves are 'nearly longitudinal' or 'nearly transverse.' This means that the elastic waves in piezoelectric elements are longitudinal or transverse only under definite specific orientation. The method available till now for determining the quartz resonator characteristics gave the highly accurate values of spectrum frequencies and attenuation amplitudes of the main and side resonances with respect to the main resonance amplitude, but those method did not allow to determine the vibration mode precisely. The holographic interferometry method makes it possible to control the behavior of vibration modes of low-frequency piezoelectric elements of quartz resonator. Spectral characteristics of piezoelectric elements of low-frequency quartz resonator have been studied by interferograms. The existence of the same side resonators in piezoelectric elements of one and the same cut, but of different geometric dimensions can be explained by physical nature of acoustic wave propagation in an anisotropic body.

Within the framework of geometrical optics a mathematical model has been created that permits to compute the conversion of polarization of a light ray passing through a multimode optical fiber with taking into account a birefringence directed radially along the fiber axis and Faraday rotation caused by a magnetic field.

The results are presented of pulsed laser diagnostics of the process of pyrolysis of hydrocarbons in a gas, aimed to obtain carbon clusters and to deposit them in a solid phase. The pyrolysis is carried out in a gas flow reactor using homogeneous gas heating by pulsed laser radiation.

To achieve the record temporal velocities at the detection of optical signals it is necessary to understand in details the processes, taking place in photocathode and near it. In the first instance, it is necessary to study the nature of photocounts, the basic effect of photodetecting. This effect was lately studied not very well and, as we shall see, it contains some problems.

Several examples for preparations of quantum states and of quantum measurements are presented. The analysis of these procedures have shown that the minimal error of the energy ΔE may be limited in some cases by γ/τ, (where τis the time of preparation or measurement) or may be significantly smaller in other cases. The possibilities to observe the existence of the shortest natural time interval τ_planck approximately equals 10^-43s are discussed. One of the possible ways to observe this phenomenon is based on the decoherence measurement of the macroscopic test mass which is well isolated from the heat bath and optimally coupled with Quantum Non Demolition meter.

The age of high-speed photography exceeds a century and may be divided into three epochs: recording of fast events being illuminated with short light bursts; opto-mechanical recording with mechanical shutters, rotating drums, prisms and mirrors; and high-speed recording with the help of electron imaging tubes. During the third epoch the authors have been enthusiastically involved into pico-femtosecond image- converter physics and technology by establishing fundamental principles and experimental realization of ultrafast image- tube photography.

Short historical overview of pico-femtosecond photography at the Kurchatov Institute is presented. It is shown how the basic principles of pico- and femtosecond image-converter photography were formulated in the fifties.

During the last four decades, the pico-femtosecond image- converter photoelectronics was established as one of the most efficient area for investigation of ultrafast phenomena in physics, chemistry, biology and medicine. Our analysis is based on research completed in Lebedev Physical Institute and General Physics Institute (GPI), Russian Academy of Sciences.

High-speed mirror camera model 203-M is described. It is further development of the base model 203 and is designed for the single-shot recording of quick processes which radiation spectrum is both in visible and infrared regions up to wavelengths of 11 micrometer. The camera is equipped with two interchangeable drives for mirror rotor: one with electric motor and the other with gas turbine. The letter makes it possible to register an event at the frequency of 600 X 10³ frames/s.

High-speed mirror cameras are mainly used for investigations of quick processes in a wide spectral range of radiation including ultraviolet and infrared regions (from 0.2 to 11 micrometer). High-speed shutters for these cameras must be non-selective and when opened must transmit the whole radiation without refraction, absorption and scattering. Electromechanical, electrodynamic and induction-dynamic shutters possess such properties because their optical channels contain no medium. Electromechanical shutters are devices where the displacement of the working blind which opens or closes an aperture is produced by a spring. Such shutters are relatively slow and are capable of closing an aperture of 50 mm in diameter in 10 - 15 ms. Electrodynamic and induction-dynamic shutters are devices where displacement of a blind is produced by the electromagnetic interaction between circuits with electric currents. In induction-dynamic shutter the secondary circuit is current-conducting blind itself in which a short-circuited loop forms. The latter is more quick because of the lower mass of its moveable secondary circuit. For this reason induction-dynamic shutters with a flat primary circuit coil and a tightly fitted to it load- bearing aluminum plate have been investigated. The blind which opens or closes an aperture was attached to this plate. The dependencies of cut-off time on the form, size and the number of turns of the primary circuit coil, on size, type of material, thickness and weight of the load-bearing plate and the blind, as well as on capacitance in the discharge circuit and the capacitor voltage have been investigated. The influence of the environmental atmosphere on the cut-off time was also studied. For this purpose the shutter was placed into the chamber where vacuum up to 10^- atm could be produced. As a result the values of the above mentioned parameters have been optimized and the designs of the shutters which are shown have been developed.

High-speed photographic camera ROTA-MIR is described which is capable of registering fast processes both in chronographic and frame-by-frame regimes. The latter regime is obtained using object irradiation by a shot pulse light source. The camera has a gas-turbine drive mirror rotor with rotation speed up to 150 thousand revolutions per minute. Entrance lens optics is changeable and provides discrete magnifications 5x, 1x and 0.55x. Two types of photographic films, 35-mm and 70- mm, can be used in the camera.

The possibility to use information theory for determination of real optical channel features and optical storage capacities as well as for option of the best image reconstruction procedure is considered. The information approach to determination of required optical channels quality and needed data processing algorithms is developed and the mathematical descriptions necessary for those purpose have been obtained. The reconstruction accuracy is shown to be determined only by the difference between output image entropy and noise one. The computer simulation procedure to estimate lower bound of experimental errors that is possible to reach in principle is proposed.

In the paper, we consider the problem of simultaneous determining the structure of a probe signal varying in time and a one-dimensional transmission function, that characterizes the influence of object on the signal. The peculiarity of solution is that one does not need any special determination of the transmission function. Moreover, in the course of processing, one does not need to use any iteration procedures, which may simplify the treatment and reduce the time required. In order to determine the amplitudes and phases of the signal under investigation and the transmission function, one has to obtain four independent functional relations. To this end, one uses the modulating-spectral approach, that is, the input and output signals are additionally modulated in a certain way that somehow implies visualizing the phase. Besides, one should form the spectrums of the signals so that four independent intensity distributions are registered. The first intensity distribution is registered for tested signal without additional modulations, i.e., determined solely by the transmission function. The second distribution is for the signal undergone an additional modulation before passing the media, while the third one, on the contrary, is for the signal modulated afterwards. At last, the fourth distribution describes the signal undergone the both additional modulations. In principle, having the four functional dependencies for the concrete modulations, one can determine the spectral representations of the signal and the transmission function, i.e. their original structure.

A version of the solution of the problem of simultaneous determination of the structure and characteristics of a two- dimensional signal and two-dimensional complex transfer or instrumental functions is considered. The solution is based on measurements of four independent intensity distributions for spectral representation of a signal: I_sr((omega) _x, (omega) _y) for a signal subjected to the transfer function, I_smr((omega) _x, (omega) _y) for a signal affected by additional specially produced modulation and the transfer function, I_srn((omega) _x, (omega) _y) for a signal of the form I_sr((omega) _x, (omega) _y) with a certain additional modulation at thy output, and I_smrn((omega) _x, (omega) _y) for a signal of the form I_smr((omega) _x, (omega) _y) with a certain modulation at the output. The intensity distributions obtained in the work make it possible to calculate the amplitude and phase components of the signal being analyzed and the transfer function. Additional modulations should provide visualization of phase information in one form or another. Linear amplitude modulation, which represents a particular form of spatial modulation, is analyzed. For this case, concrete expressions making it possible to calculate the amplitude and phase characteristics of the spectra of the signal being analy and the transfer function and, therefore, the characteristics of both the signal itself and the transfer function are obtained.