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2212 results about "Light modulation" patented technology

Electro-optical modulator and light quantum computer

The embodiment of the invention provides an electro-optical modulator and a light quantum computer. The electro-optical modulator comprises an electrode assembly and an optical waveguide assembly. The electrode assembly comprises a positive signal electrode, a negative signal electrode, a first grounding electrode and a second grounding electrode, and the positive signal electrode and the negative signal electrode are arranged between the first grounding electrode and the second grounding electrode. The optical waveguide assembly is configured to bear optical signals and comprises a first optical waveguide and a second optical waveguide, the first optical waveguide is located between the positive signal electrode and the negative signal electrode and used for bearing first optical signals, and the second optical waveguide is located between the first grounding electrode and the positive signal electrode or between the second grounding electrode and the negative signal electrode and used for bearing second optical signals. The carrier is used for bearing second optical signals. Constant-amplitude voltage signals with opposite phases are applied to the positive signal electrode and the negative signal electrode which are tightly coupled, so that the modulation efficiency can be improved, and the common-mode noise can be reduced.
Owner:SHANGHAI TURING INTELLIGENT COMPUTING QUANTUM TECHNOLOGY CO LTD +1

Wide-field dynamic magnetic imaging device and method

PCT designated stageWO2026020308A1Optically investigating flaws/contaminationFluorescence/phosphorescenceFluorescence modulationMagnetic image
A wide-field dynamic magnetic imaging device and method. The wide-field dynamic magnetic imaging device comprises: a probe assembly (1), comprising a diamond (101) containing NV centers; a microwave magnetic field assembly (2) configured to generate a uniform microwave field and a uniform bias magnetic field in the vicinity of the diamond (101), so as to regulate the spin energy level of the diamond (101) and the quantum state evolution process; a laser modulation assembly (3) configured to output an initial uniform pulsed laser to excite the diamond (101) to emit fluorescence; a fringe light modulation assembly (4) configured to modulate the initial uniform pulsed laser to output a fringe pulsed laser, causing the fluorescence emitted by the diamond (101) to be fringe fluorescence, or to modulate the fluorescence emitted by the diamond (101) into fringe fluorescence; a fluorescence detection assembly (5) configured to perform spatial imaging on the fringe fluorescence to obtain magnetic field information of a sample under test (7), thereby obtaining an initial magnetic image of said sample (7); and a data processing assembly (6) configured to perform Fourier transform and inverse Fourier transform on the initial magnetic image to obtain a first magnetic image.
Owner:UNIV OF SCI & TECH OF CHINA +1

Wave plate polarization conversion-based light spot shaping device and use method

The invention discloses a light spot shaping device based on wave plate polarization conversion and a use method, and relates to the technical field of laser processing, the device divides random polarized light into S / P light through a first polarization beam splitter (PBS), converts the S light into P light through a first 1 / 2 wave plate, modulates the S light through a conventional silicon-based liquid crystal spatial light modulator (LCoS SLM), and converts the P light into the S light through a second 1 / 2 wave plate. And the beams are combined by the second PBS. The method comprises the steps of light splitting, polarization conversion, phase modulation, beam combining, beam expanding and focusing and the like. The double 1 / 2 wave plates are combined with the conventional PBS, the laser energy utilization rate is higher than 85%, commercial SLM equipment is adapted, the machining efficiency of the shaped annular light spots is remarkably improved compared with that of Gaussian beams, the method is suitable for laser welding and metal 3D printing, and the problems of energy waste and high cost are solved.
Owner:JIANXIN OPTOELECTRONICS (SUZHOU) CO LTD

Microspace structure light three-dimensional reconstruction system and method

The system comprises a projection module, an imaging module and a phase resolving module, the projection module comprises at least three light source units and light modulation units corresponding to the light source units, an emergent light path of at least one light source unit is provided with an optical coupling assembly, and the emergent light path of at least one light source unit is provided with an optical coupling assembly. The light modulation unit is used for carrying out gradient phase modulation on a light beam, and the optical coupling assembly couples a light path modulated by the light modulation unit to a coaxial light path of the imaging module; the imaging module is arranged on a path sharing the same optical axis with the optical coupling assembly and is used for acquiring a stripe image modulated on the surface of the measured object; the phase resolving module is used for solving a wrapping phase of the fringe image output by the imaging module and unwrapping the wrapping phase based on a quality image guided space phase unwrapping algorithm; while the high-frequency sine fringe generation capability is ensured, collaborative optimization of phase distribution and light intensity characteristics is realized, and the contradiction between device miniaturization and optical performance is effectively reconciled.
Owner:TSINGHUA SHENZHEN INTERNATIONAL GRADUATE SCHOOL

Path planning method and device based on photon pulse reinforcement learning network

The invention discloses a path planning method and device based on a photon pulse reinforcement learning network, and relates to the field of photon pulse reinforcement learning networks, and the method comprises the steps: adjusting the phase of each phase shifter in an explicit MZI network according to a multi-level pulse neural network, and configuring a weight matrix; carrying out pulse signal loading on the light source by using a light modulator to obtain an input signal; obtaining a plurality of linear calculation results by using the weight matrix and the input signal through an interference effect and a coupling effect; inputting the plurality of linear calculation results into the DFB-SA laser, and obtaining a nonlinear activation result by adjusting the injection current of a gain region of the laser and the reverse bias voltage of a saturation region of the laser; and taking the nonlinear activation result as a new input signal, and returning to the step of obtaining a plurality of linear calculation results by using the weight matrix and the input signal until calculation of all levels in the pulse neural network is completed, so that path planning which is high in speed, low in power consumption and easy to configure is realized.
Owner:XIDIAN UNIV

Spontaneous-stimulated Raman co-localization single cell substructure atlas analysis system and method

The invention relates to the technical field of spectral imaging detection, in particular to a spontaneous-stimulated Raman co-localization single-cell substructure atlas analysis system and a spontaneous-stimulated Raman co-localization single-cell substructure atlas analysis method. The system comprises a femtosecond pulse excitation module used for outputting two beams of broadband femtosecond pulse laser with different frequencies and continuously adjustable optical power; the Stokes light modulation module is used for modulating the Stokes light and carrying out space beam combination on the Stokes light and the pump light; the pump light modulation module is used for modulating pump light; the spontaneous Raman laser continuous adjusting module is used for outputting spontaneous Raman laser; the stimulated Raman exciting light co-positioning module is used for combining the combined laser and the spontaneous Raman laser again, focusing the combined laser and the spontaneous Raman laser on a sample, exciting a stimulated Raman scattering signal, converting the stimulated Raman scattering signal into a digital signal and carrying out data acquisition; and the spectrum detection module is used for collecting the spontaneous Raman scattering light which is reflected and returned along the original light path, and collecting a spectrum signal to form a Raman spectrum. The method has the advantage of improving the accuracy of single-cell heterogeneity structure and cancer cell type discrimination.
Owner:CHANGCHUN INST OF OPTICS FINE MECHANICS & PHYSICS CHINESE ACAD OF SCI

Adjustment method of laser processing apparatus, and laser processing apparatus

An adjustment method of a laser processing apparatus includes a spatial light modulator adjustment step of adjusting a spatial light modulator into a state ready for splitting a laser beam emitted from a laser oscillator and applying a plurality of laser beams such that laser beams will have a desired positional relation, a processing mark formation step of operating the laser oscillator to apply the laser beams to a wafer such that a plurality of processing marks is formed, an imaging step of stopping the laser oscillator, and imaging the processing marks formed at the wafer, and an aberration correction step of correcting aberration of the condenser by comparing the desired positional relation and a positional relation among the imaged processing marks, and adjusting the spatial light modulator such that the positional relation among the processing marks conforms to the desired positional relation.
Owner:DISCO CORP

Transparent part defect detection method and system based on dual-optical-path phase deflection technology

The invention discloses a transparent part defect detection method and system based on dual-optical-path phase deflection, and belongs to the technical field of optical detection. The system comprises a camera, a reflection light source, a spectroscope, a backlight light source and a processing unit. The detection method comprises the steps of primary measurement, product overturning, secondary measurement and defect comprehensive analysis and classification. A depth map and a modulation degree map of the surface of a product are obtained through reflective measurement, a phase difference map and a backlight modulation degree map are obtained through transmission-type zero reference surface differential measurement, multi-dimensional data are fused, and accurate detection and classification of concave and convex points, foreign matter, scratches and other defects are achieved according to preset logic. The method can effectively eliminate inherent errors of the system, realizes double-sided full detection without omission, is high in detection precision and accurate in defect classification, and is suitable for defect detection of transparent parts such as multilayer transparent glass.
Owner:FREESENSE IMAGE TECH

Laser frequency stabilization system based on Faraday anomalous dispersion atomic filtering

The invention discloses a laser frequency stabilization system based on Faraday anomalous dispersion atomic filtering, which is used for carrying out frequency stabilization on phase modulation multi-sideband laser, and comprises a frequency doubling laser unit which is configured to comprise a fundamental frequency seed light source, an electro-optical modulator, a fundamental frequency amplifier and a frequency doubling crystal; the light splitting module unit is configured to split the frequency doubling light into a main output light path and a monitoring light path; the atomic optical rotation filter is located on the monitoring light path and is configured to maintain the purity of the frequency-stabilized laser spectrum through purification treatment under the control of the axial magnetic field and the temperature; the frequency stabilization unit is configured to be a frequency stabilization light path and a servo system, and the frequency stabilization light path is used for obtaining laser frequency information and generating an error signal; the servo system is used for controlling the frequency of the fundamental frequency seed light source according to the error signal feedback. According to the laser frequency stabilization system provided by the invention, the spectrum purification and frequency stabilization precision can be improved, so that high-frequency stability locking is realized.
Owner:NATIONAL INSTITUTE OF METROLOGY CHINA

Second harmonic characterization system based on spatial light regulation and control

The invention relates to a secondary harmonic characterization system based on spatial light regulation and control. The secondary harmonic characterization system comprises an incident light path unit, a detection light path unit and a sample table, the incident light path unit sequentially comprises a laser, a polarizer, a half-wave plate, a light modulator, a long-pass optical filter and an incident objective lens in the light beam incident direction; a wafer is carried on the sample table; the detection light path unit sequentially comprises an adjustable detection objective lens, a light path adjuster, a polarization analyzer, a short-pass optical filter and a detector in the light beam reflection direction; according to the SHG signal representation detected by the detector, all control parameters of the light modulator, the adjustable detection objective lens, the light path adjuster and the sample table are regulated and controlled, and the SHG signal receiving efficiency of the detector is improved. According to the invention, it is ensured that the detector efficiently receives the SHG signal, and the SHG characterization precision is improved.
Owner:INST OF MICROELECTRONICS CHINESE ACAD OF SCI LTD

High-power picosecond pulse train laser with programmable sub-pulse energy and method

The invention discloses a high-power picosecond pulse train laser with programmable sub-pulse energy and a method, and relates to the related technical field of lasers, the high-power picosecond pulse train laser comprises a mode-locked fiber laser, an acousto-optic modulator and a solid amplification chain which are sequentially arranged along an optical transmission path; the mode-locked fiber laser generates a mode-locked picosecond pulse sequence; the acousto-optic modulator performs pulse selection and pulse string grouping on the mode-locked picosecond pulse sequence, and performs pre-programming shaping on sub-pulse energy in a pulse string according to set intensity distribution to generate a pre-shaped pulse string; the solid amplification chain comprises at least one stage of solid amplifier, and the solid amplifier comprises a dichroscope, a laser gain crystal, a coupling optical assembly and an LD pumping source; and the dichroscope is used for focusing the pre-shaped pulse string amplified at the previous stage and the LD pump light transmitted by the coupling optical assembly into the laser gain crystal. Independent programmable regulation and control of the energy of each sub-pulse in the pulse string are realized, and the energy distribution of each sub-pulse in the pulse string can be flexibly adjusted.
Owner:SHANDONG UNIV

Spatial light modulator, self-checking device thereof and light computing device

The invention provides a spatial light modulator, a self-checking device thereof and a light computing device, and relates to the technical field of optical modulation.The spatial light modulator comprises an incident waveguide structure, a covering plate, a liquid crystal layer, a substrate and an emergent waveguide structure; the incident waveguide structure is optically coupled with the cover plate and is used for guiding externally incident laser into the cover plate at a preset angle; the covering plate is used for enabling laser to be propagated in the covering plate in a total reflection form; the substrate bears the liquid crystal layer, integrates the driving circuit and is used for applying regulation and control voltage to the liquid crystal layer; the liquid crystal layer is arranged on the lower side of the covering plate and used for conducting phase modulation on the laser transmitted to the liquid crystal layer in a total reflection mode in response to the regulation voltage. And the emergent waveguide structure is optically coupled with the covering plate and is used for guiding the laser modulated by the liquid crystal layer out of the covering plate to a free space. According to the spatial light modulator, efficient spatial modulation and accurate control of the light field are realized, so that the integration and function accuracy of the spatial light modulator in self-inspection and light calculation are improved.
Owner:SOUTHEAST UNIV

Projector and projector system

A projector includes a first light source, a light modulator that modulates visible light output from the first light source to form a projection image, a first relay optical system that forms the projection image at a first position, an enlarging optical system, an invisible image generator that forms an invisible image made of invisible light, and a light combiner that is disposed in the optical path between the enlarging optical system and the light modulator and combines the visible light and the invisible light with each other into combined light. The invisible image is formed at a second position conjugate with the position where the projection image is formed. The enlarging optical system forms an image at the first position and projects the combined light to display the projection image and the invisible image on a single projection surface.
Owner:SEIKO EPSON CORP

On-line rotor and stator axial clearance measuring device and method based on optical carrier microwave interference

The invention discloses a rotor and stator axial clearance online measuring device and method based on optical carrier microwave interference. The measuring device comprises a broadband light source, a first polarization maintaining optical fiber, an electro-optical modulator, a second polarization maintaining optical fiber, an optical fiber circulator, a first single-mode optical fiber and a coated optical fiber probe which are connected in sequence, and the coated optical fiber probe directly faces the axial end face to be measured; a first port of the optical fiber circulator is connected with the second polarization maintaining optical fiber, a second port of the optical fiber circulator is connected with the first single-mode optical fiber, and a third port of the optical fiber circulator is sequentially connected with the second single-mode optical fiber, the photoelectric detector, the signal conditioning unit, the signal acquisition unit and the digital processing unit; the signal acquisition unit is connected with the micro-control unit, the micro-control unit is connected with the microwave frequency sweep signal generation unit, and the microwave frequency sweep signal generation unit is connected with the electro-optical modulator. According to the invention, non-contact on-line high-precision measurement of the axial clearance of the rotor and the stator of the aero-engine under the conditions of limited measurement space and complex signal leading-out path can be realized.
Owner:TIANJIN UNIV +1

Double-optical-comb-cavity modulated gas measurement system and method based on electro-optical modulation

The invention provides a double-optical-comb-cavity modulated gas measurement system and method based on electro-optical modulation, in the use process, a detection optical comb and a reference optical comb which are coherent are generated through a double-optical-comb output module, the detection optical comb enters a resonant cavity to interact with gas to be measured, and the reference optical comb directly reaches a data acquisition and analysis module; the data acquisition and analysis module is communicated with the resonant cavity and the double-optical-comb output module, and is used for receiving the reference optical comb and the detection optical comb output from the resonant cavity, and performing component and concentration analysis on the to-be-detected gas according to the detection optical comb and the reference optical comb; in the measuring process, the electro-optical modulation module is used for acquiring the detection optical comb output from the resonant cavity in real time, and the optical field of the detection optical comb in the resonant cavity is dynamically modulated based on the detection optical comb, so that the optical comb mode is matched with the free spectral range of the resonant cavity in real time, and efficient coupling is formed in the resonant cavity; the influence of the gas dispersion effect on the measurement precision is eliminated.
Owner:NORTHWESTERN POLYTECHNICAL UNIV

Single laser printing device and method capable of modulating line width

The invention relates to a single laser printing device and method capable of modulating line width. The device comprises a focusing unit, a galvanometer unit, a light beam adjusting module and an angle adjusting module, wherein the light beam adjusting module and the angle adjusting module are sequentially arranged in front of laser light paths of the focusing unit and the galvanometer unit; the light beam adjusting module is used for modulating circular laser into long-strip-shaped laser and modulating the length of the long-strip-shaped laser according to the size of a pattern at a printing position when the same straight line is scanned; the long-strip-shaped light beams are always parallel to one another during galvanometer scanning, and laser energy in variable-width lines scanned by the galvanometer is evenly distributed. The angle adjusting module is used for adjusting the line width direction of the long-strip-shaped laser to be perpendicular to the scanning direction of the galvanometer unit. For different positions in each printing area, the laser is modulated into long-strip-shaped laser with the width consistent with the width of an image at the printing position through the light beam adjusting module, then the width direction of the long-strip-shaped laser is perpendicular to the scanning direction of the galvanometer through the angle adjusting module, and scanning of one printing area can be achieved only through one-time scanning of the galvanometer unit. And the printing precision is ensured while the printing efficiency is greatly improved.
Owner:AMSKY TECHNOLOGY CO LTD

Laser interferometer and light splitting device

Provided are a laser interferometer capable of reducing the frequency of a signal calculated and processed in a demodulation circuit and reducing the cost of the demodulation circuit, and a spectroscopic device provided with the laser interferometer. A laser interferometer is provided with: an optical modulator that adds a modulation signal to laser light using a resonator element; a light receiving element that detects a change in the intensity of the laser light including the sampled signal and the modulated signal, and outputs a laser reception signal; a signal oscillation unit that generates a reference signal of a first frequency with the vibration element as a source vibration; and a demodulation circuit that demodulates the sampled signal from the laser reception signal on the basis of the reference signal, the demodulation circuit comprising: a DC offset removal unit that removes the offset; a first phase regulator that regulates the phase of the reference signal; a first multiplier that multiplies the laser reception signal by a reference signal; a first filter; a second multiplier multiplying the first multiplication signal by a reference signal; a second filter; and a phase calculator that calculates a phase.
Owner:SEIKO EPSON CORP

Dual-mode gravitational acceleration precision measurement system and method based on light floating effect

The invention provides a dual-mode gravitational acceleration precision measurement system and method based on a light floating effect. According to the system, a 1064nm laser double-beam correlation structure is adopted, a strong focusing light trap is formed in a gravity orthogonal direction, and micron-sized silicon dioxide particles are stably captured. In the absolute measurement mode, the acousto-optic modulator is used for controlling the on-off of the laser, the high-speed position detection module is used for detecting and recording the free falling motion trail of the particles and the displacement amplitude showing the resonance state after re-capturing, and the absolute gravitational acceleration parameter is inverted. In a relative measurement mode, weak focusing 532nm laser is configured along the gravity direction to construct a gravity compensation light trap, and after absolute gravitational acceleration reference measurement is completed, the laser is modulated by an acoustic optical modulator to accurately balance the gravity of particles, so that the particles enter a quasi-balance state. When the external gravitational field changes slightly, the characteristic displacement of the particles in the gravity direction is extracted, and the change of the relative gravitational acceleration can be monitored continuously.
Owner:BEIHANG UNIV

ODAC (Optical Digital-to-Analog Converter) implementation system and method based on five-segment thermo-optical phase modulator

The invention discloses an ODAC implementation system and method based on a five-segment thermo-optical phase modulator, and relates to the technical field of optical communication, and the method comprises the following steps: obtaining single-mode laser input, dividing the single-mode laser input into two paths through a multi-mode interference device beam splitter, and transmitting the single-mode laser input into an upper arm and a lower arm of a Mach-Zehnder modulator; the current is adjusted through the thermo-optic phase modulator to control the temperature, the refractive index is changed to introduce phase delay, and the phase difference of two arms of the Mach-Zehnder modulator is calibrated; on the basis of a five-segment thermo-optical modulator, hierarchical amplitude modulation is carried out on beam splitting light according to digital input, a phase space is constructed by utilizing weight combination, and a linear optimal discrete state is screened; the modulated light is combined by a multi-mode interference device beam combiner, and digital-analog mapping output of light intensity is carried out; a detector installed at an output port of the five-segment thermo-optical phase modulator is used for monitoring output optical power in real time, the output optical power is fed back to a control circuit to calculate errors, thermo-optical modulation current is dynamically adjusted to compensate offset point drift, and optical digital analog conversion is achieved.
Owner:SHENZHEN ZHONGKE TIANYING TECH CO LTD

Multi-component gas concentration detection system

The present invention discloses a multi-component gas concentration detection system, which relates to the field of gas concentration detection, and comprises: a light source, which is used for emitting detection light covering the absorption wave band of a target gas; the light splitting assembly is used for dispersing the detection light and at least splitting the detection light into a first light beam and a second light beam; the air chamber is provided with an optical signal detection module and an acoustic signal detection module; the first light modulator is used for carrying out wavelength selection and modulation on the second light beam; wherein the first light beam is received by the light signal detection module to form an absorption spectrum detection light path; the second light beam is absorbed by the gas to be detected and then excites a sound wave signal through a photoacoustic effect, and the sound wave signal is received by the sound signal detection module to form a photoacoustic spectrum detection light path. By adopting the scheme, synchronous detection of multi-component gas, compactness of a detection structure and high-sensitivity detection of low-concentration gas can be considered.
Owner:SHANGHAI CHEYITIAN TECH CO LTD

Electro-optic modulator and method of forming the same

Various embodiments may relate to an electro-optic modulator. The electro-optic modulator may include a waveguide configured to carry optical light along a longitudinal length of the waveguide. The electro-optic modulator may also include a first electrically conductive sub-wavelength grating on a first side of the waveguide, the first electrically conductive sub-wavelength grating including a plurality of fingers extending substantially perpendicular to the longitudinal length of the waveguide. The electro-optic modulator may further include a second electrically conductive sub-wavelength grating on a second side of the waveguide opposite the first side, the second electrically conductive sub-wavelength grating including a plurality of fingers extending substantially perpendicular to the longitudinal length of the waveguide. The electro-optic modulator may be configured to modulate the optical light upon application of a potential difference between the first electrically conductive sub-wavelength grating and the second electrically conductive sub-wavelength grating based on Pockels effect.
Owner:AGENCY FOR SCI TECH & RES

Infrared complex image formation of moving targets and sub-mirror array synthetic aperture imaging method and system

The present disclosure provides a method and system for forming an infrared complex image of a moving target and performing synthetic aperture imaging using a sub-mirror array. The method comprises: using a spatial light modulator to phase-modulate an initial linearly polarized laser local oscillator to obtain an orthogonal phase-modulated laser local oscillator; using a depolarizing beam splitter in each sub-mirror module to combine the orthogonal phase-modulated laser local oscillator and a target infrared signal processed by Fourier transform to obtain a combined beam signal; using a direct array detector to receive the combined beam signal, generate a holographic image corresponding to the sub-mirror module, and combine the laser local oscillator image to construct an infrared complex image corresponding to the sub-mirror module; and performing synthetic aperture imaging on the infrared complex images corresponding to the multiple sub-mirror modules based on sub-mirror array parameters and target distance parameters to obtain a synthetic aperture imaging result, wherein the infrared complex images corresponding to each of the multiple sub-mirror modules are obtained at the same moment during the motion of the moving target.
Owner:AEROSPACE INFORMATION RES INST CAS

Health data intelligent early warning method and system

The invention relates to the technical field of digital health, in particular to an intelligent health data early warning method and system.The method comprises the steps that multi-channel signals such as electrocardio signals, pulse oximeter signals and continuous blood pressure signals which are synchronously filtered are injected into an erbium-doped annular cavity through light modulation to generate delay chaos, and sparse binary vectors are obtained through frequency domain hash coding; the vector predicts a future cardiovascular state through a spiking neural network and a reversible ordinary differential equation network; inputting the continuous prediction frame into a reversible tensor flow network, and obtaining a risk vector through anti-fact disturbance; splicing risks, states, codes and contexts to calculate risk energy, and outputting personalized intervention actions by means of a diffusion generation model; and synchronously updating model parameters and coupling coefficients according to the rewards. According to the invention, millisecond-level prospective early warning, low-power-consumption operation and interpretable intervention are realized, and the method is suitable for long-term wearable health monitoring.
Owner:ZHEJIANG TONGJI VOCATIONAL COLLEGE OF SCI & TECH

High performance optical modulators and drivers

An interface for an optical modulator and the optical modulator are described. The interface includes first and second differential line pairs. The first differential line pair has a first negative line and a first positive line arranged on opposing sides of a first waveguide. The first negative line is on a distal side of the first waveguide relative to a second waveguide. The first positive line is on a proximal side of the first waveguide relative to the second waveguide. The second differential line pair has a second negative line and a second positive line arranged on opposing sides of the second waveguide. The second negative line is on a distal side of the second waveguide relative to the first waveguide. The second positive line is on a proximal side of the second waveguide relative to the first waveguide. The first and second waveguides each include lithium niobate and / or lithium tantalate.
Owner:HYPERLIGHT CORP

Electro-optical modulator and modulation method thereof

The invention provides an electro-optical modulator and a modulation method thereof, the electro-optical modulator comprises a substrate, a buried oxide layer and a lithium niobate waveguide layer are sequentially stacked on the substrate, and the lithium niobate waveguide layer comprises a first optical waveguide and a second optical waveguide; the electrode layer comprises a composite traveling wave electrode and a direct-current electrode, and the direct-current electrode is arranged on one side, in the signal transmission direction, of the composite traveling wave electrode; wherein the composite traveling wave electrode comprises a metal electrode and a polymer electrode, the metal electrode is embedded into the buried oxide layer, the polymer electrode is arranged on the surface of the buried oxide layer, and the composite traveling wave electrode is arranged between the first optical waveguide and the second optical waveguide and arranged on the side faces of the first optical waveguide and the second optical waveguide respectively; wherein the direct current electrode is arranged between the first optical waveguide and the second optical waveguide. The electro-optical modulator is high in electro-optical conversion efficiency, the plasma effect caused by light field coupling is effectively avoided, and the light loss of the device is remarkably reduced.
Owner:INST OF SEMICONDUCTORS - CHINESE ACAD OF SCI

Normally-on flexible liquid crystal dimming film and preparation method thereof

The invention relates to the technical field of liquid crystal devices, and particularly discloses a normally-on flexible liquid crystal dimming film and a preparation method thereof. The structure of the normally-on flexible liquid crystal dimming film sequentially comprises a first flexible transparent substrate, a first vertical alignment layer, a dye liquid crystal layer, a second vertical alignment layer and a second flexible transparent substrate from top to bottom, wherein the materials of the first vertical alignment layer and the second vertical alignment layer are selected from side chain type transparent polyimide materials; the dye liquid crystal layer comprises black dichroic dye and negative phase liquid crystal. By accurately controlling the orientation arrangement of liquid crystal molecules, a high-precision pretilt angle is realized, the light modulation amplitude in a visible light broadband range reaches 45% or above, and the photoelectric property is equivalent to that of a normally dark (forward) mode liquid crystal dimming film.
Owner:AVIC BEIJING AERONAUTICAL MFG TECH RES INST

Self-adaptive underwater single-pixel imaging technology based on Fourier modulation

The invention discloses a self-adaptive underwater single-pixel imaging technology based on Fourier modulation, belongs to the technical field of computational optical imaging, is used for ocean detection and improvement of ocean surveillance and defense efficiency, and adopts a self-designed LED array to replace an expensive DMD and a four-quadrant detector composed of common photodiodes to replace an expensive barrel detector. And high-speed illumination and parallel acceptance are realized while the cost is greatly reduced. The technical route comprises a high-speed underwater single-pixel imaging device, a high-speed Fourier single-pixel imaging algorithm and an adaptive sampling strategy based on Fourier single-pixel imaging. The high-speed single-pixel imaging device comprises a self-designed LED array light modulation module, a converging lens module and a receiving module. The high-speed Fourier single-pixel imaging algorithm comprises a binarization algorithm based on error diffusion and an algorithm based on adaptive compressed sensing. According to the innovative self-adaptive sampling strategy based on Fourier single-pixel imaging, a specific sampling path is generated by fusing circular sampling and random sampling according to the characteristics of an image in a Fourier spectrum, so that Fourier coefficients which have great influence on image quality are acquired as much as possible under water with low sampling rate and high turbidity, and the image quality is improved. Therefore, the high-efficiency imaging of the underwater target object is realized, and the imaging speed and quality are both considered.
Owner:CHINA UNIV OF PETROLEUM (EAST CHINA)

Image recognition method and recognition system

The invention relates to the field of image recognition, discloses an image recognition method and an image recognition system, and systematically solves the core pain point of traditional document recognition through optical-topology fusion processing and a dynamic resource allocation mechanism. The image recognition method is composed of an acquisition module, a grid module, a phase module, a setting module and a distribution module, pixel brightness is calculated and coded based on document RGB data, and a two-dimensional coding matrix is generated; constructing a geometric correction grid, forming a nonlinear constraint field, and enhancing the anti-deformation capability of the image; generating spiral phase light waves in the constraint field by using a spatial light modulator, and generating a time-varying phase map; determining a local topology index by detecting the number of phase jump times; and extracting the closed boundary region as a character block, and generating an analysis result file. The system breaks through traditional limitation, improves image geometric correction precision, feature extraction sensitivity and boundary judgment accuracy, efficiently completes document analysis, and is suitable for scenes such as document digitization and information retrieval.
Owner:JIANGSU GUANGGUANG INFORMATION SYSTEM CO LTD

Wide-range narrow-linewidth laser wavelength and linewidth measuring system

The invention relates to the technical field of laser light source measurement, and discloses a wide-range narrow-linewidth laser wavelength and linewidth measurement system, which can be flexibly matched with the center frequency of laser to be measured through the arrangement of a tunable laser, breaks through the strict limitation of the existing beat frequency method on the center frequency, effectively expands the measurement range, and improves the measurement accuracy. By combining the synergistic effect of the absorption cell and the locking loop, the system stability is improved, the measurement precision of narrow linewidth laser is guaranteed, the integration time can be flexibly adapted without tedious adjustment of a delay optical path or change of parameters of acquisition equipment through the cooperation of the optical modulator and the delay optical fiber, the problem of inconsistent measurement resolution under different integration time is avoided, and the measurement accuracy is improved. And the accuracy of short-time measurement is obviously improved. The system integrates wavelength and line width measurement functions, can measure line width, center wavelength and long-time frequency stability of to-be-measured laser, is reasonable in structural design, retains the advantage of high precision of a beat frequency method, overcomes the defects that an existing method is narrow in measurement range and inconvenient to adjust integral time, and improves the measurement accuracy of the to-be-measured laser. And the measurement requirements of wide-range and narrow-linewidth laser are met.
Owner:XIAN INST OF OPTICS & PRECISION MECHANICS CHINESE ACAD OF SCI

Bragg light generation system and method applicable to Bragg-type atomic interferometers

This invention relates to a Bragg light generation system and method suitable for Bragg-type atomic interferometers. The system includes: a laser for generating a first laser beam with a frequency in a preset atomic absorption peak band; an optical circulator for propagating the first laser beam to a cascaded acousto-optic modulator and receiving two third laser beams returned from the cascaded acousto-optic modulator; a cascaded acousto-optic modulator for diffracting the first laser beam into two second laser beams with opposite propagation directions through Bragg diffraction of two acousto-optic crystals; an optical assembly for performing secondary diffraction on the two second laser beams and reflecting the two mutually perpendicular second laser beams to the cascaded acousto-optic modulator; and an output module for splitting and sampling the two third laser beams and modulating the sampled third laser beams into Bragg laser beams in the target frequency band. This invention reduces the path separation of the two Bragg laser beams by using a quasi-common optical path, thereby reducing phase noise and improving measurement accuracy.
Owner:CENT CHINA OPTOELECTRONICS TECH RES INST (CHINA STATE SHIPBUILDING CORP 717TH RES INST)