64 results about "Polarization modulation" patented technology

The present application belongs to the field of geophysical exploration and geoscience information sensing technology, and relates to an intelligent sensing system for ground construction risk monitoring, comprising: a pulse generation module for generating a detection pulse sequence with a preset time interval; an orthogonal polarization modulation module for mapping the detection pulse sequence with an orthogonal polarization state and loading a time delay modulation; a distributed sensing module for receiving pulse combination and generating a backscattering signal; a common mode interference cancellation module for superimposing the backscattering signal in the photon domain to generate a phase push effect, in-situ canceling a static resident stress background noise, and extracting a dynamic birefringence phase shift amount; and a signal decoupling analysis module for identifying a dynamic shear signal according to a covariance tensor principal eigenvalue extraction value. The present application utilizes an optical domain physical interference cancellation mechanism to annihilate static background interference, realizes high-fidelity physical extraction of weak dynamic signals, and improves the identification ability of the system for structural medium shear instability.

This invention proposes a multi-target detection method based on entangled photons. First, a pump light is generated using a continuous narrow-linewidth semiconductor laser, which, after polarization modulation and focusing, illuminates a PPKTP crystal. A spontaneous parametric down-conversion process generates polarization-entangled photon pairs, which are then separated into signal and reference light. These are received by a single-photon detector to obtain two time series. Second, coincidence measurements are performed on the time series in different scanning directions within the observation area to obtain a coincidence count matrix. Then, a two-dimensional constant false alarm rate (CFAR) detection algorithm is introduced, using ordered statistics to estimate background noise and adaptively adjust the detection threshold to screen candidate target points. Third, a density clustering algorithm based on correlation strength weighting is employed, combining the correlation strength and spatial distribution of entangled photon pairs to detect different targets and suppress isolated noise. Finally, the coincidence count peak points within each target cluster are selected as the final detection targets, thereby achieving multi-target detection with unknown numbers and randomly distributed locations.

The application discloses an optical element subsurface defect detection method and system based on phase contrast digital holography, and belongs to the field of precision measurement technology; the system adopts annular Bessel beam Kohler illumination, utilizes polarization modulation technology and a specially-made polarization contrast ring to realize synchronous four-step phase shift high-speed quantitative phase measurement in a U-shaped light path; the method acquires complex amplitude through a polarization camera, compensates for resolution loss by using a self-supervision super-resolution reconstruction algorithm fused with a physical model; full-field and local inverse diffraction reconstruction is carried out based on angular spectrum diffraction theory, high-precision depth positioning is realized based on the diffraction light complex amplitude distribution characteristics as a focusing criterion; three-dimensional information representation of defects is realized in combination with an optical field scattering and diffraction model and a machine learning algorithm; the application can realize high-sensitivity, high-signal-to-noise ratio, real-time in-situ quantitative detection and three-dimensional reconstruction of submicron defects without significantly increasing the cost.

This invention discloses a polarization state modulation method based on regular polyhedral constellation points, comprising: selecting the order of polarization modulation and the corresponding regular polyhedral class; dividing the original binary bitstream into a conventional modulation bitstream and a polarization state modulation bitstream, wherein the conventional modulation bitstream is used to generate conventional modulation symbols, and the polarization state modulation bitstream is used for polarization state mapping; obtaining the corresponding polarization state description parameters using the polarization state modulation bitstream and the order of polarization modulation, determining the polarization weighting factor and performing polarization weighted fusion to obtain dual-channel high-dimensional modulation symbols to be transmitted; transmitting the symbols through an orthogonal dual-polarization antenna after preprocessing; performing RF front-end processing on the received horizontal and vertical polarization components of the RF signal at the receiving end to obtain the Jones vector representation of the baseband received signal; recovering the polarization state information by combining the Stokes parameters, and recovering the original binary bitstream by combining the conventional modulation and demodulation results.

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.

The application discloses an optical signal inner circulation delay system based on electro-optic polarization modulation, comprising a signal light source, a first polarization beam splitter prism, a first electro-optic polarization modulator, a second polarization beam splitter prism, a second electro-optic polarization modulator, a third polarization beam splitter prism, a first full reflection mirror, a first lens, a first optical fiber collimator, a single-mode / multi-mode optical fiber, a second lens, a second optical fiber collimator and a second full reflection mirror, forming a ring-shaped light path. The length of the single-mode / multi-mode optical fiber and the high level duration of the modulation electric signal are adjusted, the repetition frequency and the pulse width of the output optical signal can be changed respectively, and therefore the application can also be used for converting continuous light into controllable pulsed light. The number of times that the signal light circulates in the ring-shaped light path can be controlled through the loaded electric signal, the delay time is flexibly adjusted, and the delay time range is expanded.

The application discloses a Brewster window stack polarization modulation device. The device comprises a Brewster window stack assembly, a clamping assembly, and an installation base. The Brewster window stack assembly comprises a plurality of optical window pieces arranged in parallel and at intervals, and the included angle between the surface normal and the incident light is a Brewster angle. The installation base has a vertical part and a horizontal part. The clamping baffle is arranged opposite to the vertical part of the installation base at intervals. The optical window pieces and the gaskets are alternately arranged in parallel at intervals. One adjusting screw is arranged on each side of the installation base. The adjusting screw passes through the clamping baffle and each gasket in sequence, and is screwed with the vertical part of the installation base. The rotation of the adjusting screw is converted into the linear motion of the clamping baffle along the support surface, so as to change the distance between the clamping baffle and the vertical part and / or realize the clamping and fixing of the Brewster window stack assembly. The device can realize linearly polarized light output with high extinction ratio and high stability in a wide range of incident angles and spectral bands.

This invention discloses a chip testing device and a chip testing method. The device includes a probe module, a polarization-modulated multispectral optical path system, an excitation sampling unit, and a heterogeneous data fusion processing system. The probe module includes an opaque carrier, a transparent element embedded in a hole in the carrier, and a cantilever probe array arranged at the bottom of the carrier. The polarization-modulated multispectral optical path system is arranged above the transparent element. The excitation sampling unit is used to apply power pulse excitation to the chip under test, and can simultaneously acquire the electrical response sequence generated by the probe module and the optical feature image stream acquired by the polarization-modulated multispectral optical path system. The heterogeneous data fusion processing system includes a visual recognition module and a physical inversion module. The visual recognition module is used to identify stress distortion regions from the optical feature images. The physical inversion module substitutes the stress distortion regions into the PINN model, combines the electrical response sequence, and inversely deduces the deep physical state variables inside the chip under test.

The application discloses an aluminum alloy floor protective layer defect image recognition method and system, relates to the technical field of computer vision image recognition, and comprises several function modules, including: a three-dimensional morphology pre-perception module, which obtains three-dimensional point cloud data of the surface of an aluminum alloy floor protective layer, calculates a local normal vector and a high light reflection risk coefficient, and divides a field of view into a low-curvature area and a high-curvature area to be scanned based on the high light reflection risk coefficient; an adaptive polarization regulation and control imaging module, which calculates an optimal extinction angle for the low-curvature area according to the local normal vector, fixes a detection angle, collects a single frame of polarized image, performs detection angle gradual scanning with the optimal extinction angle as the center for the high-curvature area to be scanned, and collects a plurality of polarized image sequences; and a multi-frame polarization fusion and defect enhancement module, which establishes a physical model of light intensity change with a detection angle for a plurality of polarized image sequences pixel by pixel, and separates a non-polarized light intensity component image and a polarization modulation amplitude image through fitting.

The application discloses a polarization perception adaptive defogging method and device based on autonomous prompts, which is based on Fourier polarization modulation, obtains a descriptor according to a polarization input feature image, projects the descriptor into a latent space with a set scale to obtain a descriptor under a scale s, obtains a reparameterized prompt word according to a prompt library based on a polarization characteristic and the descriptor under the scale s, and finally inputs an intensity input image into a prompt enhancement U-Net module based on a cross attention mechanism to obtain a defogged image according to the reparameterized prompt word and the intensity input image. Therefore, the application constructs a high-robustness image processing method for extreme atmospheric environment, and improves the generalization ability and robustness in a complex environment.

This invention relates to a multi-field-of-view coding method and system based on intermediate image plane polarization mask modulation, belonging to the field of space optics technology. It addresses the technical problems in existing technologies where feature aliasing and mutual interference easily occur when multi-field-of-view signals are superimposed, and where encoded features are easily distorted in the presence of optical errors or system deviations. The coding method includes the following steps: multi-field-of-view division; polarization coding parameter allocation; polarization modulation implementation; optical folding and signal superposition; and coding result output. The multi-field-of-view coding method and system based on intermediate image plane polarization mask modulation of this invention, by introducing polarization modulation in the imaging stage, maps multi-field-of-view spatial information to the polarization dimension, realizing an extension from traditional "scalar intensity coding" to "vector polarization coding."

This invention relates to the field of optical communication technology and proposes an optoelectronic fusion transmitter and method based on all-silicon technology. The transmitter includes an optical transmitter, an all-silicon photodetector, and a control circuit. The all-silicon photodetector performs real-time in-situ acquisition of multi-wavelength random polarization modulation signals and optical signals from internal nodes of the optical transmitter. The optical signals are converted into monitoring electrical signals and sent to the control circuit. The all-silicon photodetector is a serpentine waveguide avalanche photodetector. An avalanche multiplication region with a reverse bias voltage is configured at the starting end of the serpentine waveguide. As the optical signals from internal nodes of the optical transmitter propagate along the serpentine waveguide, they are absorbed segment by segment, generating primary photogenerated carriers. These carriers are amplified by the avalanche multiplication effect in the high-field region to form the monitoring electrical signal. By employing an all-silicon photodetector, polarization management, multi-wavelength channel allocation, electro-optic modulation, and closed-loop power control are integrated onto a unified all-silicon technology platform, improving the integration level.

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.

A modulator unit for modulating the polarization of an optical signal includes a light source, a polarization-dependent phase modulator, and a reflector. The light source outputs an optical signal and emits it as the input signal directed at the phase modulator. The optical signal contains a first and a second polarization components having a first and a second polarization directions, respectively. The phase modulator modulates a first phase of the first polarization component in the first polarization direction and passes on the modulated input signal to the reflector. The reflector retroreflects the received optical signal towards the phase modulator and changes its polarization by 90°. The phase modulator modulates a second phase of the second polarization component of the retroreflected optical signal in the first polarization direction. The modulator unit outputs the modulated optical signal as the polarization-modulated output signal.

This invention discloses a linear polarization beam splitting unit and a real-time monitoring device and method for the polarization degree of a linearly polarized laser. The monitoring device includes a polarization modulation unit, a polarization beam splitting unit, a photoelectric detection unit, and a signal processing unit. The polarization beam splitting unit includes a first polarization beam splitter and a second polarization beam splitter. The first polarization beam splitter receives the test light and splits it into a first transmitted light and a first reflected light. The first reflected light serves as the incident light for the second polarization beam splitter, which further splits the first reflected light into a second transmitted light and a second reflected light. This invention completely separates and extracts the main polarization component leaked by the first polarization beam splitter due to factors such as installation angle deviation, thermal drift, and mechanical vibration, using the second polarization beam splitter, directly restoring the true power extreme value of the orthogonal polarization direction of the laser under test.

A display apparatus (500; 700; 130), a picture source (200), an on-board system and a vehicle. By means of arranging a polarization modulation module or a filter module at a position optically conjugate to an eye box of a user, a polarization direction of picture light is changed by means of polarization modulation, and the filter module is used to perform selection on picture light of different polarization directions, such that a picture generation unit (201; 701) uses all pixels to generate two adjacent picture frames, thereby realizing the separation of picture light at different viewing angles, which not only ensures a high resolution of display, but also avoids the provision of a polarizing element at the position of the eye box of the user, thereby facilitating the implementation of a display system of an autostereoscopic picture and providing a more comfortable user experience for a viewer. In addition, left-eye and right-eye stereoscopic views can be more accurately controlled by means of the polarization characteristics and filtering selection of the picture light, thereby reducing the crosstalk between left-eye and right-eye pictures and achieving the effect of improving the display quality.

The application discloses a kind of simultaneous differential and phase diversity photonic time stretching systems of dual polarization modulation.The system realizes differential modulation by X and Y polarization state in a single dual polarization quadrature amplitude modulator, and realizes phase diversity by using two dual polarization quadrature amplitude modulators respectively arranged at different bias operating points.The system comprises a pulse generation module, a signal modulation module, a polarization separation module and a data processing module.The pulse generation module generates pre-chirped optical pulses.The signal modulation module modulates radio frequency signals, so that the radio frequency signals carried by the X and Y polarization sub-modulators in the two modulators are differential signals.The polarization separation module separates the X and Y polarization states by a polarization beam splitter.The data processing module uses maximum ratio combining algorithm to suppress the power periodic fading caused by dispersion.The present scheme greatly reduces the sampling rate requirement of the backend ADC, and realizes high-fidelity real-time acquisition of ultra-wideband transient signals with low-cost hardware.

This invention relates to the field of mineral conveying technology, and more particularly to a machine vision-based system for detecting and separating impurities in quartz glass raw materials. The system employs a data acquisition module to obtain image datasets of the quartz glass raw materials and synchronous environmental parameters. A raw material feature extraction module extracts particle size distribution and transmittance characteristics to determine the raw material's feature values. A raw material feature classification module classifies the raw materials into coarse-grained, high-transmittance or fine-grained, low-transmittance types based on the feature values, synchronous environmental parameters, and classification thresholds. An active optical modulation module applies polarization-modulated light or wavelength-selective modulation light based on the raw material type. A modulation analysis and processing module acquires the modulated light image, analyzes it, and outputs impurity information and early warnings. This invention achieves adaptive selection of optical modulation strategies based on the particle size and transmittance characteristics of the raw materials, overcoming the problem of missed detection caused by optical interference, improving the accuracy of impurity detection and system adaptability, and meeting the technical requirements for continuous and stable production of high-purity quartz sand.

A system for characterizing chiral molecules including an interaction zone arranged to receive a sample of chiral molecules; a laser source arranged to emit pulsed laser radiation, the laser radiation being suitable for interacting with the molecules in the interaction zone; a polarization modulator arranged to elliptically polarize the laser radiation; an optical cavity configured to redirect the pulsed laser radiation into the interaction zone several times; a detector arranged to measure a chiroptical signal produced by the interaction between the molecules and the laser radiation; and a determiner arranged and / or programmed to determine at least the chirality of the molecules from the detected chiroptical signal.

The present disclosure relates to the field of polarization computation imaging, and provides an infrared integrated polarization intelligent computation imaging system, which comprises an incident optical lens, an infrared polarization detection chip and an intelligent processing electric chip. The incident optical lens is arranged on the incident surface of the infrared integrated polarization intelligent computation imaging system, and is used for converging incident infrared light to the infrared polarization detection chip. The infrared polarization detection chip is used for polarization modulation of the incident infrared light, completion of light convolution operation, and output of the obtained light signal after being converted into an electric signal. The intelligent processing electric chip is used for processing the electric signal output by the infrared polarization detection chip, so as to obtain a polarization feature image of a detection target. The present disclosure reduces the convolution calculation amount of the back end, reduces the data transmission pressure and the back end intelligent processing pressure, can identify a target in a complex background through polarization information, further improves the image processing speed, reduces the volume, power consumption and weight of the imaging system, and realizes high-integration intelligent image processing on the end side.

The application provides a polarization modulation method and system based on a Sagnac interferometer, belongs to the technical field of quantum communication, and has the following steps: presetting a polarization state of a polarization measurement module, adjusting a system frequency and a frequency of a modulation voltage signal, so that light intensity detected by the polarization measurement module is stable; the modulation voltage signal adopts a rectangular wave, and a duty cycle of the rectangular wave is adjusted to 50%; a delay is adjusted, so that a forward light pulse is at a high level; a high-level modulation voltage is adjusted until the light intensity detected by the polarization measurement module is maximum, and the modulation voltage at this time is recorded; different polarization states of the polarization measurement module are set, the system frequency, the duty cycle of the modulation voltage and the delay are kept unchanged, the high-level modulation voltage is adjusted until the light intensity detected by the polarization measurement module is maximum, and the modulation voltage corresponding to different theta is recorded respectively, the polarization modulation rate limitation of the Sagnac ring system is broken, and the polarization instability problem caused by the transmission delay of the electric signal is solved.

This invention provides a method and system for multidimensional multiplexing optoelectronic convolution calculation based on dual polarization modulation. The method includes: mapping a weight matrix to a Kerr optical frequency comb generated based on continuous single-wavelength laser to output an optical carrier signal loaded with the weight matrix; employing electro-optic modulation technology based on dual polarization, dual parallelism, and multidimensional multiplexing to divide the optical carrier signal loaded with the weight matrix into multiple power components; performing multi-path parallel single-sideband orthogonal amplitude modulation and merging on multiple electrical signals to be transmitted obtained from the data to be transmitted and multiple optical carrier signals loaded with the weight matrix to output an optical carrier signal loaded with the data to be transmitted and the weight matrix; performing dispersion compensation and polarization drift compensation on the signal for transmission, and outputting a delayed optical carrier signal loaded with the data to be transmitted and the weight matrix to enable the receiving end to receive the delayed signal; separating the different polarization states of the delayed signal and performing direct detection to obtain the convolution calculation result of the data to be transmitted and the weight matrix.

The application discloses a high-speed transmission type optical communication module for network attack resistance, and relates to the field of optical communication.In the device, a transmission link protection unit is used for dynamically disguising link characteristics by polarization modulation and power spectrum shaping to obtain dynamically changed link characteristics; a transmission link positioning unit is used for positioning optical domain attack characteristics and signal distortion states of the transmission link, and is used for performing optical domain attack positioning, link abnormal distortion discrimination and attack point position analysis by using an acoustic time delay fusion algorithm and a graph light distortion fusion algorithm; a transmission priority control unit is used for performing optical domain attack positioning discrimination on the transmission link by using an electrical attack sorting fusion algorithm; and a transmission encryption unit and a transmission link repair unit are cooperatively used for realizing constellation mapping encryption and optical path self-recovery.The application can improve the security and transmission efficiency of optical communication.

One aspect of the present invention is a signal detection device including a mode demultiplexer configured to convert N (N is a natural number) spatial mode signals including a plurality of higher modes excited in a transmission path fiber into N base modes and output the N basis modes, a frequency conversion unit configured to convert N optical signals into frequencies different from each other, a multiplexing unit configured to multiplex the N optical signals having frequencies that have been converted, and a reception unit configured to photoelectrically convert a multiplexed optical signal while maintaining modulation information for a phase and polarization, perform digital signal conversion and signal processing, and demodulate an original information sequence.

This invention relates to the field of automated laser chip heating processing control technology, and in particular to a laser heating rework system. The system includes a spectral mapping module that obtains wavelength drift data by analyzing transient photoluminescence spectra collected by a fluorescence thermometer, and uses this data to identify the coordinates of poorly heated locations to generate a transient thermal state matrix. A tensor calculation module combines the microscopic orientation data of the material's crystal lattice structure to calculate the thermal conductivity coefficient and generate a thermal conductivity tensor matrix. A polarization synthesis module retrieves photon absorption cross-section difference parameters to inversely deduce a physical compensation array and generate a spatial polarization phase map. A polarization modulation device generates a non-uniform vector polarized light field based on this map, driving a laser output device to inject the light field into the coordinates of the poorly heated location to perform targeted heat injection. This invention utilizes the difference in physical absorption rate of photons with different polarization states in the underlying crystal lattice arrangement to correct local thermal distribution anomalies while achieving zero thermal damage overflow in the surrounding area, thus improving the overall processing yield.