Abstract: In some examples, automatic OTDR-based testing may include determining, based on analysis of a signal that is received from a DUT that is to be monitored, whether the DUT is optically connected. Based on a determination that the DUT is optically connected, a measurement associated with the DUT may be performed.

Abstract: A method and system for imaging thermodynamic phase of clouds includes obtaining a spatially-resolved polarimetric image of a region of the sky containing a cloud using a multipixel image sensor having multiple channels corresponding to different wavelength bands, determining a value of the Stokes S1 polarization parameter of incident light on each pixel corresponding to a portion of the image containing the cloud for multiple channels corresponding to different wavelength bands, and determining the thermodynamic phase of the cloud within the image based on the values of the Stokes S1 polarization parameter. The Stokes S1 polarization parameter values determined for a first channel corresponding to a first wavelength band is used to determine a liquid thermodynamic phase, and the Stokes S1 polarization parameter values determined for a second channel corresponding to a second, shorter wavelength band is used to determine an ice thermodynamic phase.

Abstract: A method for measuring a height map of a test surface having a varying reflectivity using a multi-sensor apparatus including a pre-scan sensor and a height measuring sensor is disclosed. The multi-sensor apparatus further comprises one or more light sources configured to illuminate the test surface and a spatial light modulator. The spatial light modulator is placed in a light path between the one or more light sources and a measuring location of the multi-sensor apparatus and is configured to modulate light emitted from at least one of the light sources. The method comprises performing a measurement for determining an illumination intensity map of the test surface and a measurement for performing a height map of the test surface.

Abstract: Provided are a signal source space sensing method and apparatus, and an active sensing system. The method includes: a controller controls a signal transmitter to transmit a first signal to an object to be tested; the controller controls a signal receiver to receive a second signal, which is obtained after the first signal is transmitted by the object; the controller determines a coordinate relationship between the spatial position of said object and a signal source space according to the first signal and the second signal, wherein the signal source space is a coordinate space where the first signal transmitted by the signal transmitter is located; and the controller maps the second signal back to the signal source space according to the coordinate relationship between the spatial position of the object and the signal source space, to obtain a signal source space signal so as to reconstruct a sensing signal.

Abstract: The present invention is to provide a backscattered light amplification device, an optical pulse test apparatus, a backscattered light amplification method, and an optical pulse test method for amplifying a desired propagation mode of Rayleigh backscattered light with a desired gain by stimulated Raman scattering in a fiber under test having the plurality of propagation modes. The backscattered light amplification device according to the present invention is configured to control individually power, incident timing, and pulse width of a pump pulse for each propagation mode when the pump pulse is incident in a plurality of propagation modes after the probe pulse is input to the fiber under test in any propagation mode.

Abstract: Sub-diffraction limited magneto-optical microscopy, such as Kerr or Faraday effect microscopy, provide many advantages to fields of science and technology for measuring, or imaging, the magnetization structures and magnetization domains of materials. Disclosed is a method and system for performing sub-diffraction limited magneto-optic microscopy. The method includes positioning a microlens or microlens layer relative to a surface of a sample to image the surface of the sample, forming a photonic nanojet to probe the surface of the sample, and receiving light reflected by the surface of the sample or transmitted through the sample at an imaging sensor. The methods and associated systems and devices enable sub-diffraction limited imaging of magnetic domains at resolutions 2 to 8 times the classical diffraction limit.

Abstract: A multi-core fiber includes multiple optical cores, and for each different core of a set of different cores of the multiple optical cores, a total change in optical length is detected. The total change in optical length represents an accumulation of all changes in optical length for multiple segments of that different core up to a point on the multi-core fiber. A difference is determined between the total changes in optical length for cores of the set of different cores. A twist parameter and/or a bend angle associated with the multi-core fiber at the point on the multi-core fiber is/are determined based on the difference.

Abstract: An optical pulse test apparatus according to the present disclosure includes a light generation unit configured to generate an optical pulse for generating backscattered light beams in an optical fiber under test and generate first light having an optical frequency for amplifying backscattered light in an LP11 mode out of the backscattered light beams in two LP modes through stimulated Brillouin scattering, and second light having an optical frequency for attenuating backscattered light in an LP01 mode out of the backscattered light beams in the two LP modes through stimulated Brillouin scattering, a mode demultiplexing unit configured to input the optical pulse, the first light, and the second light generated by the light generation unit into the optical fiber under test in the LP01 mode and separate, out of the backscattered light beams generated by the optical pulse, the backscattered light in the LP11 mode, a local oscillation light generation unit configured to generate local oscillation light by which t

Abstract: The present invention provides a planar three-dimensional displacement sensor for a multiaxis machining device. With the measurement of the (planar) three-dimensional displacement sensor in the multiaxis machining device, the multiaxis machining device and a multiaxis machining compensation method are able to eliminate various deformation effects effectively.

Abstract: A compact optical time domain reflectometer (OTDR) containing a small-scale OTDR, power source, and wireless communications electronics encompassed within the confines of a spool containing a time delay fiber optic waveguide coiled about the face of the spool. Data obtained by the OTDR is transmitted by wire or wirelessly to a computer or portable wireless device for graphical plotting of said data and evaluation by the user. The integration of the time delay waveguide eliminates the need for a separate time delay waveguide and provides a more compact testing solution. The Compact OTDR with Integrated Time Delay is used to test the integrity of an optical fiber waveguide.

Abstract: A distance measurement unit includes: a distance measurement light source that outputs distance measurement light; an objective lens through which the distance measurement light and reflected light are transmitted; an imaging lens through which the reflected light is transmitted and which forms an image at an imaging position; an optical path adjustment unit that adjusts an optical path of the reflected light; and a light detection unit that detects the reflected light. The objective lens allows the distance measurement light to be transmitted therethrough in a state in which an optical path of the distance measurement light is spaced apart from a central axis of the objective lens. The optical path adjustment unit adjusts the optical path so that the imaging position of the reflected light approaches a predetermined plane. A light reception surface of the light detection unit is located to follow along the predetermined plane.

Abstract: Provided are a method and an apparatus of optical module assembly, where the method includes: when an optical module to be aligned images, controlling an alignment mechanism clamping a lens to be assembled to move in a set direction by a set movement step; when the alignment mechanism moves each time, collecting, by an image acquisition device, light spots imaged by the optical module to be aligned sequentially, and selecting a light spot with a minimum size from the collected light spots; determining an optimal position of the alignment mechanism according to at least two light spots before the light spot with the minimum size and at least two light spots thereafter; and controlling the alignment mechanism to move to the optimal position to align the lens to be assembled.

Abstract: The present invention relates to a measuring device having a structure for adjusting inclination of an observation surface of a sample with respect to a reference surface which is orthogonal to an optical axis of an objective lens, and the like. The measuring device includes a scanner, arranged on a propagation path of illumination light traveling from a light source toward the sample, configured to change an emission angle of the illumination light, and inclination information of the sample is obtained by associating a signal value of a detection signal for reflected light from the sample and the emission angle of the illumination light, while changing the emission angle of the illumination light by the scanner.

Abstract: Disclosed herein include systems, devices, computer readable media, and methods for subsampling flow cytometric event data. First and second flow cytometric event data can be transformed into a lower-dimensional space, associated with a plurality of bins, and assigned to a first bin and a second bin. Subsampled flow cytometric event data comprising the first flow cytometric event data can be generated. The subsampled flow cytometric event data can comprise the second flow cytometric event data if the first bin and the second bin are different. The subsampled flow cytometric event data may not comprise the second flow cytometric event data if the first bin and the second bin are identical.

Abstract: An optical fiber characteristic measurement apparatus (1) includes: a light source (11) configured to output a laser beam of which frequency is modulated; an incident part (12, 13, 14, and 15) configured to make the laser beam output from the light source be incident from one end and another end of an optical fiber (FUT) as continuous light (L1) and pulsed light (L2), respectively; a light detector (16) configured to detect light projected from the optical fiber and output a detection signal (D1); and a detector (17 and 18a) configured to detect, in a first period (T1) in which scattering light based on the continuous light and the pulsed light is projected from the optical fiber and a second period (T2) shorter than the first period, in which the scattering light is not projected from the optical fiber, the scattering light based on integrated values acquired by integrating the detection signal for a predetermined time.

Abstract: Disclosed is a device and method for distributed detection of straightness of a working face of a scraper conveyor based on optical fiber sensing. The device includes a broadband light source, a first optical fiber circulator array, a second optical fiber circulator array, a collimator array, a reflecting film array, a third optical fiber circulator array, and an optical path analyzer. During transmission of light emitted from the broadband light source, the light with different wavelengths is separated via several optical gratings etched on a single-mode optical fiber (SMF), and reaches reflecting films adhered to the working face of the scraper conveyor through first optical fiber circulators, second optical fiber circulators, and collimators. The light with the different wavelengths is then reflected back from the reflecting films, enters the SMF through third optical fiber circulators, and finally enters the optical path analyzer.

Abstract: The present invention has an object to provide an optical fiber test method and an optical fiber test apparatus for measuring a mode dependent loss and an inter-modal crosstalk in a fundamental mode and a first higher-order mode at a connection point of a few-mode fiber. In the optical fiber test method and test apparatus according to the present invention, the mode dependent loss and the inter-modal crosstalk in the fundamental mode and the first higher-order mode at the connection point are calculated by using an approximation expression of an inter-modal coupling efficiency that is obtained in approximating electric field distributions of the fundamental mode and the first higher-order mode in a few-mode fiber by Gaussian function and Hermite Gaussian function.

Abstract: An optical test system capable of accurately measuring a loss of each mode at each position of an optical fiber which propagates a plurality of modes is provided.

Abstract: An object of the present disclosure is to provide a frequency division multiplexing coherent OTDR, a test method, a signal processing apparatus, and a program that can maintain, even in a case where a DFB laser is used, a spatial resolution equivalent to a spatial resolution achieved when a fiber laser or an external resonant laser is used.

Abstract: An imaging device blemish detection test enclosure and techniques for an optical imaging device includes a mounting structure for mounting an optical imaging device, a first body with a concave surface, and a second body holding the mounting structure relative to the first body. The mounting structure and the second body may orient an optical axis of a lens of the optical imaging device towards the concave surface and locate the lens relative to the concave surface where the interface between the first and second bodies is outside of a lens field of view of the lens. The system may include a light source disposed in the second body and directed towards the concave surface of the of the first body providing an evenly illuminating the concave surface. The concave surface may include a surface of a spherical sector greater than a hemisphere.