Abstract: Apparatuses, systems, and techniques to train one or more neural networks using stratified sampled training data parameters. In at least one embodiment, one or more stochastic training data parameters may be stratified sampled from one or more sampling ranges to compute a gradient for updating the one or more neural networks.

Abstract: There is set forth herein an apparatus comprising: a non-contacting array of sensors adapted for positioning at a position spaced from and proximate a position of a patient; and a signal processing circuit in communication with the array of sensors, wherein the signal processing circuit is configured for: generating a plurality of time varying signals using the array of sensors; processing the plurality of time varying signals; and outputting one or more indicator based on the processing. The apparatus can be adapted for use in a variety of applications including emergency applications such as live birth applications in which neonate resuscitation protocols are observed.

Abstract: Method for limiting amount of radiation impinging on a radiation-sensitive detector device by directing radiation toward the detector, permitting the radiation to impinge upon the detector device when the radiation is below a predetermined threshold, and utilizing radiation having wavelengths different from signals of interest to initiate limiting of the radiation impinging upon the detector when the predetermined threshold is exceeded. The optical limiter includes an IR limiting layer pair selected so that energy from visible and near infrared radiation activates the optical limiter. The limiting layer pair may includes a layer closer to the source of radiation of e.g. vanadium dioxide, vanadium sesquioxide, or germanium crystal and a layer further from the source of radiation of e.g. chalcogenide glass, germanium crystal, or sodium chloride crystal.

Abstract: A night vision apparatus and method comprising employing a detector operating in the 7 to 14 microns wavelength region, converting via electronics and/or photonics the received light to the region visible to the human eye, and displaying the visible light on a display, wherein a housing contains the detector, the electronics and/or photonics, and the display.

Abstract: A night vision apparatus and method comprising employing a detector operating in the 7 to 14 microns wavelength region, converting via electronics and/or photonics the received light to the region visible to the human eye, and displaying the visible light on a display, wherein a housing contains the detector, the electronics and/or photonics, and the display.

Abstract: Method for limiting the amount of radiation impinging on a radiation sensitive detector (RSD) responsive to signals having infrared wavelengths of approximately 3 to 14 microns. Method includes: directing radiation signal through prism toward RSD; permitting radiation signal to impinge upon RSD when radiation is below predetermined threshold; and directing radiation associated with radiation signal but of different wavelengths from signals of interest on path external to prism, to initiate limiting of radiation impinging upon RSD when predetermined threshold is exceeded. Also, Total Internal Reflection device including prism having thin film coated on back surface of prism. Material making up prism and thin film are selected so that, in presence of radiation having intensity less than certain threshold, refractive index of thin film is lower than that of prism, and when radiation has intensity higher than that certain threshold, refractive index of thin film is higher than that of prism.

Abstract: An IR limiting device for a detector that is based on a micro-optomechanical cantilever array is disclosed. In the normal state, each microcantilever device in the array behaves like a mirror that reflects the infrared signal to the detector. The microcantilever device absorbs radiation outside the desired infrared region. When the radiation is stronger than a predetermined threshold, the microcantilever device bends as a result of thermo-mechanical forces, and it reflects the signal away from the detector, thereby limiting the radiation. The advantage of such a system is that each pixel in the detector can be addressed individually, and the limiting is localized.

Abstract: Method for limiting amount of radiation impinging on a radiation-sensitive detector device by directing radiation toward the detector, permitting the radiation to impinge upon the detector device when the radiation is below a predetermined threshold, and utilizing radiation having wavelengths different from signals of interest to initiate limiting of the radiation impinging upon the detector when the predetermined threshold is exceeded. The optical limiter includes an IR limiting layer pair selected so that energy from visible and near infrared radiation activates the optical limiter. The limiting layer pair may includes a layer closer to the source of radiation of e.g. vanadium dioxide, vanadium sesquioxide, or germanium crystal and a layer further from the source of radiation of e.g. chalcogenide glass, germanium crystal, or sodium chloride crystal.

Abstract: An IR limiting device for a detector that is based on a micro-optomechanical cantilever array is disclosed. In the normal state, each microcantilever device in the array behaves like a mirror that reflects the infrared signal to the detector. The microcantilever device absorbs radiation outside the desired infrared region. When the radiation is stronger than a predetermined threshold, the microcantilever device bends as a result of thermo-mechanical forces, and it reflects the signal away from the detector, thereby limiting the radiation. The advantage of such a system is that each pixel in the detector can be addressed individually, and the limiting is localized.

Abstract: Method for limiting the amount of radiation impinging on a radiation sensitive detector that is responsive to signals of interest having infrared wavelengths of approximately 3 to 14 microns, such as an infrared camera. The method includes: directing a radiation signal through a prism and toward the radiation sensitive detector; permitting the radiation signal to impinge upon the radiation sensitive detector, e.g. upon an infrared focal plane array in the camera, when the radiation is below a predetermined threshold; and directing radiation associated with the radiation signal but having wavelengths different from said signals of interest—e.g., wavelengths in the visible and near-infrared range—on a path external to the prism, in order to initiate the limiting of the radiation impinging upon the radiation sensitive detector when the predetermined threshold is exceeded. Also, a Total Internal Reflection device that includes a prism having a thin film coated on the back surface of said prism.

Abstract: An all-optical switching array for switching a direction of optical signals is presented. The all-optical switching array includes a first substrate. Furthermore, the all-optical switching array includes a plurality of optical switches disposed on the first substrate, wherein each of the plurality of optical switches comprises a first state and a second state and is configured to change the direction of an optical signal, depending on whether the optical switch is in the first state or the second state. The transition of the switch between the first state and the second state is triggered by an ultra-fast laser beam.

Abstract: The invention provides a system for generating X-rays via the process of inverse Compton scattering. The system includes a high repetition rate laser adapted to direct high-energy optical pulses in a first direction in a laser cavity and a source of pulsed electron beam adapted to direct electron beam in a second direction opposite to the first direction in the laser cavity. The electron beam interacts with photons in the optical pulses in the laser cavity to produce X-rays in the second direction.

Abstract: Disclosed herein is a method for imaging anisotropic media comprising selecting multiple points within the anisotropic media, which is to be imaged; determining an acoustic path between each selected point in the anisotropic media and a receiver position on the surface of the anisotropic media; calculating an acoustic wave velocity at all necessary points; determining an acoustic path length based on each selected point in the anisotropic media and the receiver position; determining a time delay for each acoustic wave between each image point and the receiver position on the surface of the anisotropic media; calculating a sum for each point selected based on the appropriate acoustic wave velocities and the acoustic path lengths; and generating an image of the anisotropic media using the coherent sums generated for each said image point selected.

Abstract: Holographic storage media including a substrate and a dye material capable of undergoing a photo-induced change are disclosed. Data may be written into the holographic storage media using light of one wavelength and read using light of a different wavelength.

Abstract: A method and system for localization of fluorescence in a scattering medium such as a biological tissue are provided. In comparison to other optical imaging techniques, this disclosure provides for improved spatial resolution, decreased computational time for reconstructions, and allows anatomical and functional imaging simultaneously. The method including the steps of illuminating the scattering medium with an excitation light to excite the fluorescence; modulating a portion of the emitted light from the fluorescence within the scattering medium using an ultrasonically induced variation of material properties of the scattering medium such as the refractive index; detecting the modulated optical signal at a surface of the scattering medium; and reconstructing a spatial distribution of the fluorescence in the scattering medium from the detected signal.

Abstract: The present invention provides an optical filter assembly that reduces the phase and amplitude noise of a detection laser used to detect ultrasonic displacements. The filtered detection laser is directed to the surface of a remote target. Ultrasonic displacements at the surface scatter the filtered detection laser. Collection optics then gather phase modulated light scattered by the surface and direct the phase modulated light to an optical processor to produce a signal representative of the ultrasonic displacements with an improved SNR. Additional processors may determine the structure of the remote target.

Abstract: The invention is directed to a system and method for detecting defects in a manufactured object. These defects may include flaws, delaminations, voids, fractures, fissures, or cracks, among others. The system utilizes an ultrasound measurement system, a signal analyzer and an expected result. The signal analyzer compares the signal from the measurement system to the expected result. The analysis may detect a defect or measure an attribute of the manufactured object. Further, the analysis may be displayed or represented. In addition, the expected result may be generated from a model such as a wave propagation model. One embodiment of the invention is a laser ultrasound detection system in which a laser is used to generate an ultrasonic signal. The signal analyzer compares the measured ultrasonic signal to an expected result. This expected result is generated from a wave propagation model. The analysis is then displayed on a monitor.

Abstract: An image processing method for structured light profiling includes sampling an image of a structured light pattern to obtain an intensity distribution, selecting a number of sets of sampled points from the intensity distribution. Each of the respective sets includes a number of sampled points. The image processing method further includes fitting each of the sets of sampled points to a respective distribution function and filtering the distribution functions to select a representative distribution function for the intensity distribution.