16results about "Polarisation spectroscopy" patented technology

This application relates to the field of optical polarization measurement technology, specifically to a wide-spectrum, high-bandwidth static spectral modulation Stokes polarization measurement device, comprising a polarization modulation module, a spectral sampling module, and a high extinction ratio polarizer. The polarization modulation module includes a phase retarder and a linear polarizer; the spectral sampling module has sub-nanometer spectral resolution; the high extinction ratio polarizer includes a halogen tungsten lamp and a Glan Taylor prism for generating high-purity linearly polarized light; the obtained demodulation factor and the modulation spectrum acquired by the spectral sampling module are used to invert the Stokes parameters using zero-heterodyne coherent demodulation technology. This application employs a phase retarder with high birefringence, which, for the same thickness, produces an optical path difference tens of times greater than that of quartz, increasing the Stokes polarization measurement bandwidth by a factor of the response and improving the measurement accuracy of polarization spectral parameters. Simultaneously, the zero-heterodyne coherent demodulation method is used to eliminate the dispersion interference of the phase retarder through calibration.

An optical spectrum obtaining apparatus includes: a beam splitting unit, a first / second optical spectrum computation unit, and a processing unit. The beam splitting unit is configured to: receive a light beam from a light source, split the light beam into a first polarization component and a second polarization component with different polarization directions, transmit the first polarization component to the first optical spectrum computation unit, and transmit the second polarization component to the second optical spectrum computation unit. The first optical spectrum computation unit is configured to compute an optical spectrum of the first polarization component. The second optical spectrum computation unit is configured to compute an optical spectrum of the second polarization component. The processing unit is configured to obtain an optical spectrum of the light beam based on the optical spectrum of the first polarization component and the optical spectrum of the second polarization component.

The application belongs to the technical field of precision optical instruments, and specifically discloses a general calibration method for system parameters of an ellipsometer not based on a model, which comprises the following steps: selecting standard samples of multiple categories as reference samples, placing the reference samples in an ellipsometer for polarization experiments, and collecting light intensity signals corresponding to the reference samples; obtaining light intensity matrices or light intensity coefficient matrices corresponding to the reference samples according to the light intensity signals of the reference samples; solving an analysis matrix describing an analyzing arm of the ellipsometer system and a modulation matrix describing a modulating arm of the ellipsometer system through multi-parameter joint optimization, and simultaneously obtaining characteristic parameters of the reference samples by using a nonlinear regression optimization method; applying the calibrated analysis matrix and the modulation matrix to a to-be-tested sample, and calculating based on a light intensity matrix or a light intensity coefficient matrix of the to-be-tested sample to solve optical parameters of the to-be-tested sample. The application can realize the generality and simplicity of the ellipsometer calibration process.

The application discloses a polarization multiplexed spectral imaging system based on an acousto-optic tunable filter and belongs to the technical field of spectral imaging. The system comprises, which are connected in sequence, a convergent incidence module, a spectral modulation module, a diffracted light separation correction module and an imaging module; the convergent incidence module converges and incides light into the spectral modulation module to obtain diffracted light and transmitted light with orthogonal polarization states containing specific spectra; the diffracted light separation correction module spatially separates the diffracted light and the transmitted light and shields the transmitted light, and compensates chromatic aberration and corrects inconsistency caused by polarization of the two beams of diffracted light through two branch lenses which are independent in parameters; and the imaging module combines and images the two beams of corrected diffracted light on the same pixel of a photoelectric detector, thereby solving the problem of large energy loss of a traditional acousto-optic tunable filter spectral imaging system caused by a front polarizer and realizing high-light-flux spectral imaging.

The invention relates to a measuring device (10) for measuring light (200) from a light source (2), comprising an optical unit (30) with a delay element (31) for splitting a polarized light beam (210) of the light (200) into a first partial beam (211) and a second partial beam (212) which have a defined phase shift relative to each other. The invention further relates to a measuring system (1) and a measuring method (100).

The application provides a kind of spatiotemporal modulation Fourier transform stokes polarization imaging spectrometer, including in turn along the direction of propagation of light beam: telescope system, polarization modulation system, converging system, polarization interference system and imaging system;Target scene emitted target light field is collimated into parallel light field in telescope system and is incident;Linearly polarized light field is obtained after collimated parallel light field is incident to polarization modulation system and is incident to converging system;Converging system is used to image linearly polarized light field to polarization interference system and produce superposition interference, form polarization interference imaging light field with specific optical path difference distribution characteristics and are incident to imaging system to obtain polarization interference image;By step scanning to target scene, obtain polarization interference image cube, by extracting each field of view corresponding interference order interference map, carry out stokes channel filtering and fourier transform, and then demodulate the spectral information of each stokes parameter of target light field.

The application discloses an active and passive integrated spectral polarization imaging device in an extreme light environment, and belongs to the field of target detection in an extreme light environment. The device comprises a main and passive common optical axis imaging module, a laser active illumination module, an imaging detection module and a mode control and signal processing module. The main and passive common optical axis imaging module establishes a common optical axis transmission channel in which an active emission light path and a target reflection receiving light path are spatially overlapped. The laser active illumination module provides 532nm and 808nm switchable coaxial illumination. The imaging detection module comprises a receiving imaging sub-module, a polarization modulation sub-module and a detection output sub-module, and is used for collecting intensity images and polarization images. The mode control and signal processing module realizes adaptive switching and cooperative control of an active illumination imaging mode and a passive polarization imaging mode. The device can realize natural correspondence of active intensity information and passive polarization information in space, and avoids parallax and registration errors caused by separate arrangement of multiple systems.

To provide methods and systems for performing simultaneous spectroscopic measurement of semiconductor structures at ultraviolet, visible and infrared wavelengths.SOLUTION: Wavelength errors are reduced by orienting a direction of wavelength dispersion on a detector 141 surface perpendicularly to the projection of a plane of incidence onto the detector 141 surface. A broad range of infrared wavelengths are detected by the detector 141 that includes multiple photosensitive areas having different sensitivity characteristics. Collected light is linearly dispersed on the detector 141 surface according to the wavelength. Each different photosensitive area is arranged on the detector 141 to sense a different range of incident wavelengths. In this manner, a broad range of infrared wavelengths are detected with a high signal-to-noise ratio by a single detector. These features enable high throughput measurement of high aspect ratio structures with high throughput, precision and accuracy.SELECTED DRAWING: Figure 1

Magneto-optical sensors for process or process chamber condition monitoring are described. In an example, a system includes a process chamber. The system also includes a laser source to provide a laser beam having an initial polarization, the laser beam to be directed through a first polarizer and then into the process chamber. The system also includes a magnet surrounding the process chamber, the magnet to provide a Faraday rotation of the laser beam, the laser beam to exit the process chamber and enter a second polarizer and then a detector to provide a detected polarization rotation for lock-in detection.

This invention provides an imaging device, a three-dimensional information acquisition method, and a three-dimensional reconstruction method. The imaging device includes a light source module, a light modulation system, and an imaging detector. The light source module emits broadband light within a target wavelength range towards a target object. The light modulation system includes a multifocal vector metalens, which is configured to separate the broadband light reflected from the target object into at least four target polarization states. The light modulation system separates the broadband light reflected from the target object into at least four target polarization states and into light of multiple target wavelengths, focusing them onto different imaging regions of the imaging detector to form multiple spectral atlases corresponding one-to-one with the target polarization states. Each spectral atlas includes multiple sub-images corresponding one-to-one with the target wavelengths. This improves the overall efficiency of the imaging device and also makes the imaging device more portable and has a higher degree of functional integration.

The present application relates to a kind of small-angle mueller matrix microscopic imaging spectrum system calibration method, comprising the following steps: providing standard sample and system make two compensators in system keep with certain rotation speed ratio rotation, to obtain different azimuth combinations, utilize photoelectric detection device in system to collect the light intensity data of all incident angles of incident light under different azimuth combinations;Point-to-point Fourier analysis is carried out to light intensity data under each wavelength, each incident angle, and the Fourier coefficient under different azimuth combinations is solved;Extract the Fourier coefficient spectrum under at least two different incident angles;The initial value of Fourier coefficient spectrum, system parameter is substituted into the theoretical model of mueller matrix, and the measured data of mueller matrix is calculated, which is compared with the theoretical data of mueller matrix;With the principle of reducing the difference between the two, adjust system parameter, until the two are matched.The present application provides a matching calibration method for small-angle mueller matrix microscopic imaging spectrum system, and the method is simple, accurate and efficient.

Magneto-optical sensors for process or process chamber condition monitoring are described. In an example, a system includes a process chamber. The system also includes a laser source to provide a laser beam having an initial polarization, the laser beam to be directed through a first polarizer and then into the process chamber. The system also includes a magnet surrounding the process chamber, the magnet to provide a Faraday rotation of the laser beam, the laser beam to exit the process chamber and enter a second polarizer and then a detector to provide a detected polarization rotation for lock-in detection.

The application discloses a kind of diffractive metasurface full stokes polarimetric spectrum detection system and method, belong to micro-nano optics and polarimetric spectrum detection technical field, the technical problem to be solved is the detection and reconstruction of polarimetric spectrum information, technical solution points are: optical coding module includes diffractive metasurface, the diffractive metasurface includes nanometer column arranged according to preset rule, for polarized multiplexing phase modulation and spectral dispersion coding to incident light, different polarization state and wavelength incident light information is converted into spatial diffraction distribution;Photoelectric conversion module is located on the diffraction light path of the diffractive metasurface, for single exposure recording the diffraction distribution, generates two-dimensional original intensity image;Information recovery module is connected with the photoelectric conversion module, built-in pre-trained deep learning model, for the full stokes polarimetric spectrum information of incident light in the two-dimensional original intensity image is decoupled and recovered.

An imaging spectroscopic ellipsometry apparatus and method configured to measure thin films with high spatial resolution. The apparatus includes a rotating compensator that enables to simultaneously collect both spectrometric ellipsometric data and ellipsometric imaging with the use of the same measurement beam of light. Collecting both data sets simultaneously increases the information content for analysis and affords a substantial increase in measurement performance.

This invention provides a snapshot-type Fourier transform Stokes polarization imaging spectrometer, comprising, in sequence along the beam propagation direction: a telescope system, a polarization modulation system, a converging system, a polarization interferometer system, and an imaging system. A target light field emitted from a target scene is incident on the telescope system. After passing through the telescope system, the target light field is collimated into a parallel light field and incident on the polarization modulation system. The parallel light field passes through the polarization modulation system sequentially to obtain a linearly polarized light field, which is then incident on the converging system. The converging system is used to perform multi-array imaging of the linearly polarized light field, resulting in multiple imaging light fields that are incident on the polarization interferometer system. The multiple imaging light fields generate superimposed interference at the light exit position of the polarization interferometer system, forming a polarization interferometric image field with specific optical path difference distribution characteristics. This image field is then incident on the imaging system to obtain an interferometric image array. Based on the aforementioned interferometric image array, the spectral information of each Stokes parameter of the target light field under each field of view is demodulated.

This invention belongs to the field of polarization imaging technology, specifically relating to a polarization tomography device and method based on a single-pixel detector. A polarization tomography device based on a single-pixel detector includes, from front to back, a light source module, a first modulation module, a second modulation module, an acquisition module, and an image processing module. The object to be measured is placed inside the first modulation module. The light source module emits a one-dimensional parallel beam. The one-dimensional parallel beam enters the first modulation module, is modulated by the first modulation module into beams carrying different polarization states representing information of the object to be measured, and then exits, before entering the second modulation module. The acquisition module acquires the beam signal emitted after modulation and encoding by the second modulation module, converts the beam signal into an electrical signal, and transmits it to the image processing module to reconstruct the image. The imaging device of this invention has a simple structure, low requirements for ambient light intensity, and high imaging quality.