A fiber optical coherence tomography (OCT) probe is used for three dimensional dental imaging. The probe has a
lightweight miniaturized design with a size of a pen to facilitate clinic in vivo diagnostics. The probe is interfaced with a
swept-source / Fourier domain optical coherence tomography at 20K axial scanning rate. The tooth samples were
scanned from occlusal, buccal, lingual, mesial, and distal orientations. Three dimensional imaging covers tooth surface
area up to 10 mm x 10 mm with a depth about 5 mm, where a majority of caries affection occurs. OCT image provides
better resolution and contrast compared to gold standard dental radiography (X-ray). In particular, the technology is well
suited for occlusal caries detection. This is complementary to X-ray as occlusal caries affection is difficult to be detected
due to the X-ray projectile scan geometry. The 3D topology of occlusal surface as well as the dentin-enamel junction
(DEJ) surface inside the tooth can be visualized. The lesion area appears with much stronger back scattering signal
intensity.
Infrared sensors play a critical role in detection, guidance, and targeting in today's military systems and warfighter
equipment, ranging from man-portable to space-borne. Although significant progress is being made in the development
of IR imagers, another important component of IR sensors has not evolved significantly-the optics. Current IR lenses
are primarily made of expensive single-crystal germanium with tedious mechanical fabrication operations that include
grinding, polishing, and edging. There is an industry wide need for lower cost and higher performance IR lenses.
Agiltron has developed a technology to directly mold IR lenses to net-shape without additional finishing operations.
This manufacturing technology produces optics with many-fold reductions in cost, size, weight, and fabrication time.
The ability to reproducibly manufacture aspheric optics with complex net-shapes reduces the number of lenses
traditionally required for imaging systems, providing aberration correction as well as system weight and size reductions.
Additionally, anti-reflective surfaces can be molded into the glass, eliminating the need for expensive AR coatings. This
technology utilizes a new chalcogenide glass material that reduces temperature induced index of refraction changes to
near zero, and has a thermal expansion coefficient similar to aluminum. The result is a new generation of low cost, high
performance and thermally robust IR lens systems.
We report here a novel photonic infrared scene generator based on integration of IR fiber with
MEMS attenuation technologies. We employed an infrared transmission fiber image bundles
with one end coupled to an IR light source and the other end for display. A robust
electromagnetic actuated MEMS attenuator array is incorporated into each fiber to individually
modulate the IR light intensity, forming a 2D and high grayscale scene. The design is versatile,
promising to realize the desirable performance specification for IR scene generator. Using an IR
lamp as the broadband light source, our scene generator covers the wavelength range from
2~14μm, and provides the sufficient IR power for the high apparent temperature. We reported
here a 4×4 format array demonstration unit. This performances achieved to date include: high
apparent temperature of 1700°C, high dynamic range over 40dB, high pixel isolation over 40dB,
cool ambient background, and the moderate response speed of a few ms as well as continuous
gray-scale without flick-ness.
The value of infrared imaging in defense, security and public safety applications has been well established. A number of camera technologies have been developed and are commercially available. Yet the cost, size and power consumption of the typically cryogenically cooled cameras remain a significant impediment to more widespread deployment for these missions and extended exploitation in other fields. Agiltron has been developing a MEMS microcantilever technology offering high sensitivity and expanded operating temperature range in order to address the fundamental shortcomings of currently available technology. Here we report results achieved to date with our imagers and present an analysis of the performance potential of the architecture. We derive the fundamental mechanical limit to NEDT of this photomechanical imager architecture.
One dimensional photonic bandgap structures can be used to enhance the efficiency of nonlinear optical parametric processes. Structural dispersion can be used to achieve phase matching, and resonant effects can be used to increase the intensity of the pump beams in the nonlinear optical material. In this paper these ideas are used to derive for the a continuous wave or a quasicontinuous wave THz signal and show that an improvement of three orders of magnitude in the
output intensity can be achieved for a structure involving as few as four layers of ZnTe.
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