Abstract: A method for estimating a wetted length of a solid surface includes sensing intensity of light reflected from a gas-liquid interface on the solid surface. A waveguide faces the gas-liquid interface and a diffused light is propagated to the gas-liquid interface through the waveguide. At least one optical receiver is positioned on a side of the waveguide to receive light reflected from the gas-liquid interface.

Abstract: There is set forth herein, in one example, an apparatus. The apparatus can comprise, for example: a first reaction site and a second reaction site over a single pixel. There is set forth herein, in one example, a method. The method can include, for example: detecting a signal emitted from a first reaction site and a second reaction site; determining the identity of a first analyte of interest in a first reaction site using an amplitude of the detected signal; and determining the identity of a second analyte of interest in a second reaction site using the amplitude of the detected signal.

Abstract: An apparatus, system, and method for a see-through optical verification tester are described herein. In some aspects, a heating element such as a Peltier or Thermoelectric Cooler “TEC” may be used to control a temperature of an optical element. In examples, the see-through optical transmission tester includes a see-through void and may control temperature, humidity, and pressure of an environmental enclosure to facilitate optical see-through and reflective tests.

Abstract: An optical measurement apparatus includes a light source unit generating and outputting light, a polarized light generating unit generating polarized light from the light, an optical system generating a pupil image of a measurement target, using the polarized light, a self-interference generating unit generating multiple beams that are split from the pupil image, and a detecting unit detecting a self-interference image generated by interference of the multiple beams with each other.

Abstract: A method for generating a illumination dual-comb signal that provides a low frequency train of interferograms (180) readable by a regular video-rate camera (160) comprising N pixels and a sampling frequency of V Hz to extract hyperspectral information (170), the method comprising providing a monochromatic signal, splitting the monochromatic signal in two split monochromatic signals, frequency shifting each monochromatic signal with an offset frequency below V 2 ? Hz , generating two frequency combs having a difference in repetition below V 2 ? Hz by a nonlinear modulation of the two split monochromatic signals, generate the illumination dual-comb signal, Illuminating a target and employing a video-rate camera (160) to read a low frequency train of interferograms (180) based on a reflected and/or transmitted signal of the illumination dual-comb signal and performing Fourier transformation of the low frequency train of interferograms (180) detected by each pixel from the N pixels to e

Abstract: A micro-probe laser frequency modulation interferometric ranging method and system, under the premise of not introducing an absolute laser rangefinder to introduce new uncertainties, continuously and slowly changes the modulated laser wavelength, resulting in a continuous periodic phase change in the interference signal obtained by the detector. The laser modulation absorption spectrum shifts from the initial locked absorption peak to another locked peak, and the wavelength changes of the two locked absorption peaks before and after are obtained by checking the table. Meanwhile, calculating the phase difference demodulated by the phase generated carrier (PGC) before and after, and the initial length of optical dead-path is calculated using wavelength scanning technology. Afterwards, utilizing the advantages of high relative distance measurement accuracy of micro-probe fiber optic laser interferometer, real-time measurement of the measured distance is achieved.

Abstract: A rotary encoder is incorporated in an annular space formed between a hollow rotating shaft and an encoder case. The rotary encoder has an annular printed wiring substrate, a plurality of mounting substrates that are outward from the printed wiring substrate in the radial direction and are arranged in the circumferential direction, and inter-substrate wiring cables bridged between the printed wiring substrate and each of the mounting substrates in the radial direction. Power supply to the mounting substrates and signal transmission and reception between the mounting substrates can be accomplished without routing around the wiring cables. It is possible to achieve a rotary encoder that is suitable for being incorporated in a narrow annular space.

Abstract: Optical sample characterization facilitates measurement and testing at any angle in a full range of angles of light propagation through an optical sample, such as a coated glass plate, having a higher than air index of refraction. A rotatable assembly includes a cylinder having a hollow, and a receptacle including the hollow. The receptacle also contains a fluid with a known refractive index. An optical light beam is input normal to the surface of the cylinder, travels through the cylinder, then via the fluid, to the optical sample, where light beam is transmitted and/or reflected, then exits the cylinder and is collected for analysis. Due at least in part to the fluid surrounding the optical sample, the optical sample can be rotated through a full range of angles (±90°, etc.) for full range testing of the optical sample.

Abstract: A method for distributed acoustic sensing includes sending a first optical pulse down an optical fiber, wherein light from the first optical pulse is backscattered from positions along a length of the optical fiber according to coherent Rayleigh scattering; splitting backscattered light from the first optical pulse into a first portion for a first interferometer and a second portion for a second interferometer, the first interferometer having a first gauge length and the second interferometer having a second gauge length, wherein the first gauge length is different from the second gauge length; detecting a first interferometric signal from the first interferometer responsive to the first portion of backscattered light; detecting a second interferometric signal from the first interferometer responsive to the second portion of backscattered light; and processing the first and second interferometric signals for two different sensing applications adapted for the first and second gauge lengths, respectively.

Abstract: Systems and methods for inspecting or characterizing samples, such as by characterizing patterned features or structures of the sample. In an aspect, the technology relates to a method for characterizing a patterned structure of a sample. The method includes directing a pump beam to a first position on a surface of the sample to induce a surface acoustic wave in the sample and directing a probe beam to a second position on the sample, where the probe beam is affected by the surface acoustic wave when the probe beam reflects from the surface of the sample. The method also includes detecting the reflected probe beam, analyzing the detected reflected probe beam to identify a frequency mode in the reflected probe beam, and based on the identified frequency mode, determining at least one of a width or a pitch of a patterned feature in the sample.

Abstract: Disclosed is a multi-axis atom interferometer system, including a source of cold atoms, a laser source generating a first light pulse configured in such a way as to spatially split the source of cold atoms into a first cloud of atoms propagating along a first trajectory along a first axis and a second cloud of atoms propagating along a second trajectory along a second axis, a second light pulse adapted to spatially deflect the first trajectory along the second axis and simultaneously the second trajectory along the first axis towards a first point and a last light pulse adapted to recombine the at least one part of the first cloud of atoms and the at least one part of the second cloud of atoms at the first point, and a detection system measuring an interferometric phase-shift accumulated between the first light pulse and the last light pulse.

Abstract: A method comprising: generating a pulsed laser beam comprised of non-interfering pulse-pairs having a phase difference, wherein the phase difference changes between each two consecutive cycles of the pulse-pairs; directing the pulsed laser beam at one or more optical resonators, wherein each of the one or more optical resonators is impinged by acoustic waves, to cause the pulsed laser beam to propagate through each of the one or more optical resonators, thereby interfering the pulse-pairs; and calculating shifts in a spectral response of each of the one or more optical resonators based on measuring the interference, wherein the shifts are indicative of a waveform of the acoustic waves.

Abstract: A swept-source optical coherence tomography (SS-OCT) apparatus includes a plurality of wavelength-tunable light sources. The SS-OCT apparatus includes a first optical coupler configured to receive an output from each of the plurality of wavelength-tunable light sources. The optical coupler is configured to split the received output from the plurality of wavelength-tunable light sources into a reference optical path and a sample optical path. The sample optical path is configured to illuminate a sample. The SS-OCT apparatus includes a second optical coupler configured to receive return optical signals from the reference optical path and the sample optical path, and to output an optical interference signal. The SS-OCT apparatus includes a detector configured to detect the optical interference signal; and a controller configured to receive an electrical signal based on the detected optical interference signal. The controller is configured to generate a depth profile of the sample using compressed sensing.