This PDF file contains the front matter associated with SPIE Proceedings Volume 9279, including the Title Page, Copyright information, Table of Contents, Introduction (if any), and Conference Committee listing.

We demonstrate a photonic-assisted broadband radio frequency (RF) channelization scheme based on dual coherent optical frequency combs (OFCs). The advantages include coarse optical alignment requirement, ideal rectangular frequency response in each channel without any ultra-narrow optical filters, and digitalized output for further processing. Meanwhile, the channel frequency response and crosstalk of the scheme are also evaluated experimentally.

Photonic integrated circuits facilitate possible integration of complete optical communication systems on a chip and enable chip-scale optical interconnection networks. On-chip signaling is one of the key technologies. In this paper, we review our recent research works in on-chip signaling with digital and analog modulation signals through ultra-compact integrated photonic devices. Using our designed and fabricated silicon photonic devices, 1) we experimentally demonstrate on-chip signaling of advanced multi-carrier multi-level modulation signals (e.g. OFDM m-QAM) in silicon microring resonators and silicon vertical slot waveguides; 2) we experimentally evaluate the on-chip analog signaling performance in silicon strip waveguides, silicon microring resonators and silicon photonic crystal cavities. On-chip terabit-scale digital signal transmission and low-distortion analog signal transmission are achieved in the experiment with favorable performance using silicon photonic devices.

Time-interleaved photonic analog-to-digital converter (TIPADC) is a promising candidate to process ultra-wideband signals. In a TIPADC, quantization is electrical in order to obtain large effective number of bits (ENOB). In this paper, we study the issues on the signal sampling and reconstruction in the TIPADC from the systematic point of view. The sampling output and frequency response of the system are derived using a model that includes the photonic sampling, demultiplexing, photo detecting, electronic quantizing and digital processing. The signal sampling and reconstruction mechanism of TIPADC with a uniform system sampling rate and matched channels are illuminated with the spectrum of signal in each processing step. The effect of the sampling pulse and back-end electronics on the system frequency response is analyzed in detail. The feasible regions of the system for alias-free sampling in terms of system frequency response, and a set of sampling criteria on bandwidth of the sampling pulse and back-end electronics are presented for the TIPADC. We find that the analog bandwidth of TIPADC can be much higher than the bandwidth of back-end electronics due to the weighted summing introduced by the multichannel time-interleaved photonic sampling. The proposed model and sampling criteria are validated by simulations under different parameter configurations.

All-optical sampling attracts considerable attention due to its crucial applications in high-speed optical analog-to-digital conversion. We successfully demonstrated an all-optical sampling scheme using nonlinear polarization rotation in a single semiconductor optical amplifier at 40 GSa/s and 160 GSa/s, respectively. The scheme requires only a single semiconductor optical amplifier and has low power consumption, which shows much potential for the high-speed optical analog-to-digital conversion.

A novel all-optical simultaneous pulse multiplication and shaping approach is proposed, which is based on a triply sampled spectral filter utilizing fiber Bragg grating. This proposed method enables one to create a pulse train efficiently with both a high multiplication factor and arbitrary pulse profile. As an example, pulse train with a repetition rate of 225-GHz and flat-top intensity profile is numerically demonstrated, which is generated from 1-GHz transform-limited Gaussian pulse train with pulse width of 0.4 ps.

Optical signal generation and processing are becoming increasingly important for a wide range of scientific and engineering applications, including high-speed optical telecommunications, optical computing circuits, optical biomedical imaging, advanced sensors and material/device characterization techniques. Optical approaches offer the possibility to overcome the severe speed limitations of present electronic circuits, which are practically limited to generation/processing speeds below a few tens of GHz. All-optical circuits would easily enable generation/processing speeds covering frequency bandwidths from 10s of GHz to several THz. As for conventional waveform generation/processing circuits in electronics, fundamental devices in the optical domain, such as basic processing functions and customized waveform generation schemes need to be realized and developed. Among all-optical implementation approaches, all-fiber technologies, e.g. fiber long period grating (LPG) and Bragg grating (BG), are attractive due to their simplicity, potential for low cost and full compatibility with fiber-optics and integrated-waveguide systems. The spatial resolution limitation of presently available fiber grating fabrication technologies has limited the fiber-based waveform generation/processing schemes to temporal resolutions of at least several picoseconds, i.e. corresponding to a few 100s of GHz in terms of the bandwidth of waveform generation/processing. In this work, we present our recent research results demonstrating that arbitrary optical waveforms with bandwidths well in the THz regime can be generated/processed using fiber LPG device. The proposed LPG solutions enable one to synthesize/process optical waveforms with temporal resolutions down to the femtosecond range, i.e. far faster operation bandwidths than conventional BG-based optical waveform generation/processing schemes.

A novel optical single-sideband (OSSB) signal generation with simultaneous IF signal up conversion technique is proposed to overcome the fiber dispersion problem. With this up-conversion technique, a high frequency OSSB signal is generated by using two low bandwidth intensity modulators in combination with fiber gratings. The low frequency local oscillator (LO) signal is modulated by employing frequency doubling technique or frequency quadrupling technique respectively. The OSSB radio frequency (RF) signal generated by mixing the intermediate frequency (IF) signal and low frequency local oscillator (LO) signal, is transmitted over standard single-mode fiber successfully. The received signal error vector magnitude (EVM) is 5.8% rms and 13% rms.

A simplified photonic approach to microwave frequency measurement with digital outputs based on multiple parallel optical filter arrays, is proposed and experimentally demonstrated. In the proposed approach, multiple optical phase-shifted filter arrays in parallel with different free spectral ranges (FSRs) are designed to obtain digitalized results in the form of binary code with high-coding efficiency and fine measurement resolution. In particular, compared with previous approaches, larger tolerances on the phase shifts of optical filter arrays are provided in the proposed approach having the same coding efficiency and resolution. Therefore, the proposed system is greatly simplified and robust to noise. A proof-of-concept experiment is performed when two optical filter arrays are used. 8-bit binary digitalized results with a 5-bit effective number and a 2-GHz measurement resolution are obtained in the range from 10 to 40GHz.

Fingerprint has been widely studied and applied to personal recognition in both forensics and civilian. However, the current widespread used fingerprint is identified by 2D (two-dimensional) fingerprint image and the mapping from 3D (three-dimensional) to 2D loses 1D information, which leads to low accurate and even wrong recognition. This paper presents a 3D fingerprint recognition method based on the fringe projection technique. A series of fringe patterns generated by software are projected onto a finger surface through a projecting system. From another viewpoint, the fringe patterns are deformed by the finger surface and captured by a CCD camera. The deformed fringe pattern images give the 3D shape data of the finger and the 3D fingerprint features. Through converting the 3D fingerprints to 2D space, traditional 2D fingerprint recognition method can be used to 3D fingerprints recognition. Experimental results on measuring and recognizing some 3D fingerprints show the accuracy and availability of the developed 3D fingerprint system.

This paper presents a fast 3D (Three-Dimension) palmprint capturing system and develops an efficient 3D palmprint feature extraction and recognition method. In order to fast acquire accurate 3D shape and texture of palmprint, a DLP projector triggers a CCD camera to realize synchronization. By generating and projecting green fringe pattern images onto the measured palm surface, 3D palmprint data are calculated from the fringe pattern images. The periodic feature vector can be derived from the calculated 3D palmprint data, so undistorted 3D biometrics is obtained. Using the obtained 3D palmprint data, feature matching test have been carried out by Gabor filter, competition rules and the mean curvature. Experimental results on capturing 3D palmprint show that the proposed acquisition method can fast get 3D shape information of palmprint. Some initial experiments on recognition show the proposed method is efficient by using 3D palmprint data.

Artificial compound-eye optics have been used for three-dimensional information acquisition and display. It also enables us to realize a diversity of coded imaging process in each elemental optics. In this talk, we introduce our single-shot compound-eye imaging system to observe multi-dimensional information including depth, spectrum, and polarization based on compressive sensing. Furthermore it is applicable to increase the dynamic range and field-of-view. We also demonstrate an extended depth-of-field (DOF) cameras based on compound-eye optics. These extended DOF cameras physically or computationally implement phase modulations to increase the focusing range.

Non-uniform image blur caused by camera shake or lens aberration is a common degradation in practical capture. Different from the uniform blur, non-uniform one is hard to deal with for its extremely high computation complexity as the blur model computation cannot be accelerated by Fast Fourier Transform (FFT). We propose to compute the most computational consuming operation, i.e. blur model calculation, by an optical computing system to realize fast and accurate non-uniform image deblur. A prototype system composed by a projector-camera system as well as a high dimensional motion platform (for motion blur) or original camera lens (for optics aberrations) is implemented. Our method is applied on a series of experiments, either on synthetic or real captured images, to verify its effectiveness and efficient.

The invention of the optical frequency comb technique has revolutionized the field of precision spectroscopy, providing a way to measure the absolute frequency of any optical transition. Since, frequency combs have become common equipment for frequency metrology. In the last decade, novel applications for the optical frequency comb have been demonstrated beyond its original purpose. Broadband molecular spectroscopy is one of those. One such technique of molecular spectroscopy with frequency combs, dual-comb Fourier transform spectroscopy provides short measurement times with resolution and accuracy. Two laser frequency combs with slightly different repetition frequencies generate pairs of pulses with a linearly-scanned delay between pulses in a pair. The system without moving parts mimics a fast scanning Fourier transform interferometer. The measurement speed may be several orders of magnitude faster than that of a Michelson-based Fourier transform spectrometer, which opens up new opportunities for broadband molecular spectroscopy. Recently, dual-comb spectroscopy has been extended to nonlinear phenomena. A broadband Raman spectrum of molecular fingerprints may be measured within a few tens of microseconds with coherent Raman dual-comb spectroscopy. Raster scanning the sample leads to hyperspectral images. This rapid and broadband label-free vibrational spectroscopy and imaging technique might provide new diagnostic methods in a variety of scientific and industrial fields.

Fluorescence imaging using radio frequency-multiplexed excitation (FIRE) has emerged to enable an order-of-magnitude higher frame rate than the current technologies. Similar to all high-speed realtime imaging modalities, FIRE inherently generates massive image data continuously. While this technology entails high-throughput data sampling, processing, and storage in real-time, strategies in data compression on the fly is also beneficial. We here report that it is feasible to exploit the radio frequency-multiplexed excitation scheme in FIRE for implementing compressed sensing (CS) without any modification of the FIRE system. We numerically demonstrate that CS-FIRE can reduce the effective data rate by 95% without severe degradation of image quality.

We report frequency estimation of loudspeaker diaphragm vibrating at high speed by parallel phase-shifting digital holography which is a technique of single-shot phase-shifting interferometry. This technique records multiple phaseshifted holograms required for phase-shifting interferometry by using space-division multiplexing. We constructed a parallel phase-shifting digital holography system consisting of a high-speed polarization-imaging camera. This camera has a micro-polarizer array which selects four linear polarization axes for 2 × 2 pixels. We set a loudspeaker as an object, and recorded vibration of diaphragm of the loudspeaker by the constructed system. By the constructed system, we demonstrated observation of vibration displacement of loudspeaker diaphragm. In this paper, we aim to estimate vibration frequency of the loudspeaker diaphragm by applying the experimental results to frequency analysis. Holograms consisting of 128 × 128 pixels were recorded at a frame rate of 262,500 frames per second by the camera. A sinusoidal wave was input to the loudspeaker via a phone connector. We observed displacement of the loudspeaker diaphragm vibrating by the system. We also succeeded in estimating vibration frequency of the loudspeaker diaphragm by applying frequency analysis to the experimental results.

We demonstrate single-shot multiwavelength digital holography using a monochromatic image sensor and spacebandwidth capacity-enhance experimentally. Multiple wavelength information is multiplexed on the monochromatic image sensor plane in the space domain and is separated in the spatial frequency domain by utilizing the the spatial frequency of interference fringes. Both transmission and reflective multiwavelength digital holography systems can be constructed with a simple optical setup. The recordable space bandwidth utilized for object waves is extended by the space-bandwidth capacity-enhance. Both the three-dimensional and multiple wavelength information of an object with rough surface and a transparent specimen was recorded and reconstructed without unwanted image components.

The hyper-spectrum data exhibits the structure, materials, and semantic meaning of a nature scene and its fast acquisition is of great importance due to its potential for parse these properties of dynamic scenes. Targeting for high speed hyperspectrum imaging of a nature scene, this paper proposes to capture the coded hyper-spectrum reflectance of a nature scene using low cost hardware and reconstruct the latent data using a corresponding decoding algorithm. Except for a wide spectrum light source, the imaging system includes mainly a commercially available projector color wheel and a high speed camera, which work at their own constant periods and are self-synchronized by our algorithm. The introduced light source and color wheel cost less than 50 dollars and makes the proposed approach widely available. The results on the data captured by our prototype system show that, the proposed approach can reconstruct the high precision hyper-spectrum data at real time.

This paper investigates the random bitstream ranging model and proposes a new output SNR model based on statistical optics theory. We study the relationship of SNR and the fraction of 1 in bitstream with different dead time by Monte Carlo simulation. Theory model is almost consistent with Monte Carlo simulation. The results show that with the fraction of randomly distributed 1-bits in transmitted pattern increased, the system SNR gets better first and then gets worse. Best pattern of transmitted bit stream according to different dead time leads to the best SNR. According to new output SNR model, low dead time brings better SNR. The system SNR increases firstly then gets down with the growing signal photon counts. At last, Gaussian distribution timing jitter of 440ps FWHM is introduced to reconstruct received bitstream pattern formed from the arrival times of returning single photon. We find that higher rate of bitstream brings higher possibility error of single time value. Suitable bits rate is restricted to 1 GHz according to jitter of 440ps FWHM to reduce the probability of ranging error.

This article describes a method of the timing sequence design for CMOS image sensor LUPA-4000. A FPGA based imaging system with the function of adjustable integration time, multiple-slope integration, parallel integration an reading, windowing readout has been designed. This design can satisfy the frequency of 66M limit frequency of LUPA-4000 and 20 frames of a second. As the fixed noise of LUPA-4000 is aloud and the image is not clear, an efficient real-time image processing algorithm is also described in this paper. First a black image should be acquired as the fixed noise image. The real-time images can be send out after subtracting the noise image. This method can effectively eliminate the fixed noise o f the image, as the same time, the original image information has been maintained in the maximum degree. The test experiments on FPGA shows this design can drive LUPA-4000 working properly. Also this design takes full advantage of the accessibility features of the device, which provides a wider dynamic range and more flexible application of the device. The image sensor driven by this design improves imaging quality, which can be used for space exploration, especially for small space dynamic target tracking.

In the medical ultrasound imaging, the synthetic transmit aperture (STA) technique is very promising and has been a hot research topic. It is dynamically focused in both transmit and receive yielding an improvement in resolution. But this imaging technique sets high demands on processing capabilities and makes implementation of a full STA system very challenging and costly. Many attempts have been made to reduce the demands on the system making it a more realistic task to implement. In this paper we don’t consider how to reduce the demands, but consider how to accelerate the processing speed of the system. The recent introduction of general-purpose graphic processing units (GPU) seems to be quite promising in this view, especially for the affordable programming complexity. In this paper we explain the main computational features of STA processing unit, trying to disclose the degree of parallelism in the operations. On the basis of the compute unified device architecture (CUDA) programming model and the extremely flexible structure of the Single Instruction Multiple Threads (SIMT) model, we show that the optimization of STA processing unit can be performed more efficiently. The input data is read from Matlab, the post-processing and display also use Matlab. Performance shows that, using a single NIVDIA GTX-650 GPU board, this amount to a speed up of more than a factor of 30 compared to a highly optimized beamformer running on our test workstation with a 3.20-GHz Intel Core-i5 processor.

Because of its aerodynamic diameter of the aerosol particles are stranded in different parts of different human respiratory system, thus affecting human health. Therefore, how to continue to effectively monitor the aerosol particles become increasingly concerned about. Use flight time of aerosol particle beam spectroscopy of atmospheric aerosol particle size distribution is the typical method for monitoring atmospheric aerosol particle size and particle concentration measurement , and it is the key point to accurate measurement of aerosol particle size spectra that measurement of aerosol particle flight time. In order to achieve accurate measurements of aerosol particles in time-of-flight, this paper design an ECL-TTL high-speed timer with ECL counter and TTL counter. The high-speed timer includes a clock generation, high-speed timer and the control module. Clock Generation Module using a crystal plus multiplier design ideas, take advantage of the stability of the crystal to provide a stable 500MHz clock signal is high counter. High count module design using ECL and TTL counter mix design, timing accuracy while effectively maintaining , expanding the timing range, and simplifies circuit design . High-speed counter control module controls high-speed counter start, stop and reset timely based on aerosol particles time-of-flight, is a key part of the high-speed counting. The high-speed counting resolution of 4ns, the full scale of 4096ns, has been successfully applied Aerodynamic Particle Sizer, to meet the precise measurement of aerosol particles time-of-flight.

The statistical distribution of natural phenomena is of great significance in studying the laws of nature. Here, in this paper, based on laser scattering particle counter, a simple random pulse signal generating and testing system is designed for studying the counting distributions of three typical objects including particles suspended in the air, standard particles, and background noises. Moreover, in order to have a deep understanding of the experimental results from laser scattering particle counter, a random process model is also proposed theoretically to study the random law of measured results. Both normal and lognormal distribution fittings are applied to analyze the experimental results, and we have proved that statistical amplitude and width distributions of particles suspended in the air, standard particles, and background noise match well with lognormal distribution when natural numbers are used as the variables. This study is an important reference for statistical data processing for laser scattering particle counter, moreover, it will also be a useful guide for designing laser scattering particle counter with high accuracy and processing speed.

Optical computerized tomography (OCT), as a branch of computerized tomography (CT) techniques, has been widely used to display and diagnose a variety of complex flow fields, due to its characteristics of real-time, stable, non-contact and can supply 3-D distributions. In practical applications, we found some different phenomenon when they are adopted in clod and hot complex flow fields. In this paper, the cold and hot flow field’s OCT diagnosis is analyzed and compared. The results show that 1) OCT can directly reflect the spatial distribution of the measured flow field’s refractive index, for both the cold and the hot complex flow fields; 2) OCT can reflect the boundary or structure of the cold flow fields, but could not well done for the hot flow fields. The involved results will help us to make better use of OCT methods to diagnose various cold or hot complex flow fields.

An improved Brillouin-assisted photonic microwave downconverter that features simple structure and wide frequency tunable range is experimentally demonstrated. In order to obtain higher conversion efficiency, SBS-assisted notch filter is used to suppress the carrier of phase modulated signal. Due to the SBS-assisted notch-filtering is generated by the phase modulated signal itself, which simplify the system structure effectively. Furthermore, the effective suppression of the carrier of phase modulated signal and the diminishment of the second-order Stokes wave could be achieved simultaneously by optimizing the attenuation of the variable optical attenuator, which guarantee our scheme can operate over a wide frequency range.

In this paper, we experimentally demonstrate simultaneously all-optical optical time division multiplexing (OTDM) add-drop multiplexing (ADM) operation of two 80-Gbit/s OTDM signals by using a single highly nonlinear fiber (HNLF). The performance of ADM is experimental studied. The experimental results show that only a power penalty of 1.5dB for the channel dropping function and no distinct power penalty for the adding function.

In this paper, the aperture change of the aluminium alloy aerospace structure under real load is researched. Static experiments are carried on which is simulated the load environment of flight course. Compared with the traditional methods, through experiments results, it’s proved that 3D digital speckle correlation method has good adaptability and precision on testing aperture change, and it can satisfy measurement on non-contact,real-time 3D deformation or stress concentration. The test results of new method is compared with the traditional method.