G01N2021/216

Polarization property image measurement device, and polarization property image measurement method

A polarization property image measurement device includes: a first radiation unit that radiates light beams in different polarization conditions onto a target object after subjecting the light beams to intensity modulation at frequencies different from one another; a light receiving unit including first photoelectric conversion units that photoelectrically convert the light beams having been radiated from the first radiation unit and scattered at the target object in correspondence to each of the different polarization conditions, and second photoelectric conversion units that photoelectrically convert visible light from the target object; and a processor that detects signals individually output from the first photoelectric conversion units at the different frequencies and differentiates each signal from other signals so as to determine an origin of the signal as one of the light beams; and creates an image of the target object based upon signals individually output from the second photoelectric conversion units.

APPARATUS FOR CARRYING OUT POLARIZATION RESOLVED RAMAN SPECTROSCOPY
20210270669 · 2021-09-02 ·

An apparatus for carrying out polarization resolved Raman spectroscopy on a sample (15), in particular a crystalline sample, comprises: at least one light source (11), in particular at least one laser, for providing excitation radiation to a sample (15), a spectrograph (31) for dividing light from the sample (15), in particular Raman scattered light from the sample (15), into at least one spectrum of spatially separated wavelength components and for directing at least a portion of the at least one spectrum to a detector (29), in particular a CCD detector, a polarization state control element (27) for the light from the sample (15), the polarization state control element (27) being arranged in a light path of at least one light beam (25) traveling from the sample (15) towards the detector (29), and the polarization state control element (27) comprising at least one polarization sensitive optical element (45, 47), in particular a Wollaston prism, the at least one polarization sensitive optical element being adapted to split the at least one light beam (25) into at least two, in particular orthogonally, polarized light beams (35a, 35b, 37a, 37b).

VIBRATIONAL CIRCULAR DICHROISM SPECTROSCOPY
20210247307 · 2021-08-12 ·

A vibrational circular dichroism (VCD) spectroscopy method and apparatus that can significantly reduce the measurement time needed to acquire a differential absorption spectrum compared to known approaches. A dual-comb is generated by superimposing the outputs from two quantum cascade laser sources, thus providing a third comb interferogram with beat frequencies higher than the polarization modulation frequency. Consequently, for each of the left and right circularly polarized light, the measurement signal measures transmission through the sample across the full wavelength range of interest during each period of the polarization modulation. A complete vibrational spectrum is thus acquired in each modulation of a polarization modulator, instead of only acquiring data for a single wavelength during each modulation of the polarization, as in dispersive or tunable laser VCD, or only a single Fourier component of the spectrum, as in Fourier transform VCD.

SPECTROSCOPIC ANALYSIS DEVICE

A spectroscopic analysis device includes a light source configured to emit light including a plurality of wavelength components, a polarizer configured to convert the light emitted from the light source to a light of linearly polarized light to be radiated to a sample, a polarizing diffraction element configured to diffract and spectrally disperse a first polarization component included in the light having passed through the sample in a first direction, the polarizing diffraction element being configured to diffract and spectrally disperse a second polarization component included in the light in a second direction different from the first direction, a prism which is disposed on an exit side of the polarizing diffraction element and which has a first exit surface crossing the first direction and a second exit surface crossing the second direction, and in which angles of the first exit surface and the second exit surface with respect to a reference plane including the first direction and the second direction are different, an imaging element configured to capture an image of the first polarization component emitted from the first exit surface of the prism and an image of the second polarization component emitted from the second exit surface, and a processor configured to analyze the sample based on an imaging result of the imaging element.

Method and apparatus for analysing a component
11125679 · 2021-09-21 · ·

A method of analysing a component formed from a metal alloy to identify a possible defect, wherein the metal alloy comprises a first crystal grain region and the possible defect comprises a second crystal grain region aligned to a different axis to the first crystal grain region, the method comprising the steps of: obtaining a first image of the component illuminated using a first polarisation state of light, the first image comprising first polarisation data; obtaining a second image of the component illuminated using a second polarisation state of light different to the first polarisation state, the second image comprising second polarisation data; determining a difference in polarisation data for plural pixels of the first image between each pixel of the first image and a corresponding pixel of the second image; and identifying pixels corresponding to the second crystal grain region based on the difference in polarisation data.

CHOLESTERIC LIQUID CRYSTAL LAYER, LAMINATE, OPTICALLY ANISOTROPIC BODY, REFLECTIVE FILM, METHOD FOR PRODUCING CHOLESTERIC LIQUID CRYSTAL LAYER, ANTI-COUNTERFEIT MEDIUM, AND DETERMINATION METHOD

Provided are a cholesteric liquid crystal layer having an excellent reflection anisotropy, a low haze, and a high circular polarization degree of reflected light, and a method for producing the same. In addition, provided are a laminate, an optically anisotropic body, and a reflective film, each of which including the cholesteric liquid crystal layer. A cholesteric liquid crystal layer formed using a liquid crystal compound, in which, in at least one main plane out of a pair of main planes of the cholesteric liquid crystal layer, a direction of a molecular axis of the liquid crystal compound changes while continually rotating along at least one in-plane direction, the molecular axis of the liquid crystal compound is tilted with respect to the main plane of the cholesteric liquid crystal layer, and an arrangement direction of bright portions and dark portions derived from the cholesteric liquid crystalline phase, as observed under a scanning electron microscope in a cross section perpendicular to the main plane, is tilted with respect to the main plane of the cholesteric liquid crystal layer.

Configurable retro-reflective sensor system for the improved characterization of the properties of a sample

Disclosed is a retroreflector-based sensor system for optical characterization of a sample, having a transmitter for irradiating the sample, a retroflector positioned behind the sample, the transmitter, the sample, and the retroreflector being positioned such that radiation reflected back from the retroreflector is again incident on the sample and is reflected back from the latter in the direction towards the transmitter, and a receiver which is positioned in the receiving beam path such that it detects radiation reflected back from the retroreflector, incident again on the sample and reflected back from the latter, in the direction towards the transmitter.

METHOD AND APPARATUS FOR ANALYSING A COMPONENT
20210048384 · 2021-02-18 · ·

A method of analysing a component formed from a metal alloy to identify a possible defect, wherein the metal alloy comprises a first crystal grain region and the possible defect comprises a second crystal grain region aligned to a different axis to the first crystal grain region, the method comprising the steps of: obtaining a first image of the component illuminated using a first polarisation state of light, the first image comprising first polarisation data; obtaining a second image of the component illuminated using a second polarisation state of light different to the first polarisation state, the second image comprising second polarisation data; determining a difference in polarisation data for plural pixels of the first image between each pixel of the first image and a corresponding pixel of the second image; and identifying pixels corresponding to the second crystal grain region based on the difference in polarisation data.

METHOD FOR IMAGING BIOLOGICAL TISSUE USING POLARIZED MAJORANA VECTOR AND COMPLEX VORTEX PHOTONS FROM LASER AND SUPERCONTINUUM LIGHT SOURCES
20210080382 · 2021-03-18 · ·

A super class of polarized transverse vector vortex photon beams patterns are mathematically represented here, which are Majorana-like among them are the radial and azimuthal Laguerre-Gaussian, hybrid -vector beams, and Airy beams. These optical beams are consider spin-orbit coupled beams based on OAM and SAM parts of light. A Majorana photon is a photon that is identical to its anti-photon. It has within itself both chirality, right and left-handed twist in polarization (SAM) and wavefront (OAM). Applications using Majorana photons improve optical deeper imaging, higher resolution imaging, Nonlinear Optics effects (SHG, SRS, SC), optical communication in free space and fibers, quantum computer as basic qubit, and entanglement for security.

Retardation profile for stress characterization of tubing
10871400 · 2020-12-22 · ·

Provided herein are systems and methods for monitoring radial stresses in glass tubing. In some embodiments, a measurement system includes a light source delivering a light to a tube, and a polarizer receiving the light after the light is refracted through a wall of the tube. The measurement system may further include a detector receiving the light from the polarizer, the detector operable to capture a first image of the light at a first polarization state and a second image of the light at a second polarization state. The system may further include a controller operable to determine a retardation profile related to the stress profile of the wall of the tube by determining a retardation magnitude of the light refracted through the wall of the tube based on a difference between the first image of the light and the second image of the light.