26 results about "Radial polarization" patented technology

The invention discloses a precise mold micropore size feature measurement method, which comprises the following steps: S1, parameter initialization: reading a mold RFID tag to obtain a nominal hole depth H and a curvature radius R, and calculating an initial interlayer spacing dz0 = 0.1 H; s2, dynamic optical scanning: irradiating the surface of the micropore with a radial polarization annular light source, and detecting polarization angle deviation in real time through a polarization sensor; s3, layered image reconstruction: performing wavelet packet denoising on the image output in S2; s4, three-dimensional measurement: mapping the virtual edge coordinates output in S3 to a three-dimensional space; s5, diameter calculation and verification: calculating a horizontal diameter and a vertical diameter line by line in effective lines in the step S4; and S6, outputting a result. The laser incident angle is regulated and controlled in real time through polarization feedback, closed-loop compensation is performed on reflection distortion in combination with a mold curvature radius parameter, the measurement error of the diameter of a curved surface micropore is reduced from + / -8 microns to + / -1.5 microns, and curved surface self-adaptive accurate detection is achieved.

The present application relates to a kind of stress line birefringence compensation method of optical current sensor, the optical current sensor includes laser source, polarizer, magneto-optical film, nanometer ring-shaped radial polarization grating, image beam and CMOS area array camera sequentially arranged in same optical path, the method includes the following steps: utilize laser source to emit light signal, under the action of current to be measured, the output signal of optical current sensor is superposed with Faraday magnetic rotatory angle θ And stress line birefringence δ, form synchronous rotating annular light spot;Determine the zero-crossing moment of the measured alternating current, the rotation angle of corresponding annular light spot is stress line birefringence δ at zero-crossing moment by CMOS area array camera and record;Based on the stress line birefringence δ of record, utilize model-free adaptive iterative learning method to predict the stress line birefringence δ of future time, and according to the prediction result, the output signal of optical current sensor is compensated.

According to the transmitting and receiving combined transducer and the self-contained underwater acoustic beacon system, the transmitting transducer has an omnidirectional transmitting working mode and a directional transmitting working mode, and stable and reliable monitoring of the beacon system in a complex water area working environment can be achieved through switching of the working modes. The transmitting-receiving combined transducer comprises a transmitting transducer and a receiving transducer which are coaxially arranged, the transmitting transducer and the receiving transducer both adopt radially polarized piezoelectric ceramic circular tubes, the inner wall surfaces of the transmitting transducer and the receiving transducer are positive electrodes, and the outer wall surfaces of the receiving transducer are negative electrodes; the positive electrode of the transmitting transducer adopts a circumferential segmented polarization form, namely the inner wall surface of the transmitting transducer is uniformly divided into eight segments along the circumferential direction for polarization to form eight segments of positive electrodes; the eight sections of positive electrodes of the transmitting transducer are divided into four groups in a radial symmetry manner; and the input voltage of the four groups of positive electrodes of the transmitting transducer is changed, and the working modes are switched.

The present invention provides a pixel-level full-vector, full-range polarization control device, comprising: an aperture, a radial polarization converter, a first phase-type liquid crystal spatial light modulator, a second phase-type liquid crystal spatial light modulator, a PC control terminal, a converging lens, and a polarization camera. Specifically, the aperture, the radial polarization converter, the first phase-type liquid crystal spatial light modulator, the second phase-type liquid crystal spatial light modulator, the converging lens, and the polarization camera are arranged in sequence along the horizontal direction and share a common rotational symmetry axis. The present invention relates to the technical field of vector light beam polarization control. The pixel-level full-vector, full-range polarization control device of the present invention can achieve full-range polarization control of the ellipticity angle [‑π / 4, π / 4] and the azimuth angle [‑π / 2, π / 2] for light incident in any polarization state.

The invention discloses a carving machining method and system based on vector pulse laser, and belongs to the technical field of laser carving, the carving machining method based on the vector pulse laser comprises the steps that linear polarization femtosecond pulse laser is split into femtosecond pre-pulse laser and picosecond main pulse laser; adjusting the pulse time delay between the femtosecond pre-pulse laser and the picosecond main pulse laser; combining the femtosecond pre-pulse laser and the picosecond main pulse laser after delay regulation and control; the femtosecond pre-pulse laser is converted into an angularly polarized femtosecond pre-pulse light beam, the picosecond main pulse laser is converted into a radially polarized picosecond main pulse light beam, and a double-pulse light beam combination of the angularly polarized femtosecond pre-pulse light beam and the radially polarized picosecond main pulse light beam is formed; and the to-be-machined workpiece is ablated and engraved through the double-pulse light beam combination. And by means of the synergistic effect of double pulses and precise time delay, the width and fusion damage of a heat affected zone are remarkably reduced, and high-precision and low-damage carving machining is achieved.

The invention provides micro-nano machining equipment based on a longitudinal light field, and belongs to the technical field of micro-nano machining, and the micro-nano machining equipment comprises a light source module which is used for providing an input light beam; the light beam shaping module is used for receiving the light beam output by the light source module and shaping the input light beam into an annular light beam; the polarization regulation and control module is used for receiving the annular light beam output by the light beam shaping module and adjusting the polarization state of the annular light beam into radial polarization; and the focusing module is used for receiving the radial polarization annular light beam output by the polarization regulation and control module and focusing the radial polarization annular light beam on a focal plane to generate a high-purity longitudinal light field. According to the device, efficient conversion from common Gaussian light to a high-purity longitudinal light field is achieved, the device can generate sub-wavelength light spots with energy highly concentrated in the axial direction, the high-purity longitudinal light field can be stably generated, transverse field interference can be restrained, and therefore the micro-nano machining resolution is improved, and breakthrough of the traditional optical diffraction limit is facilitated.

The present invention relates to a polarization-entangled photon voltage sensor, comprising a type II self-parametric down-conversion polarization-entangled photon source, a high-potential sensing optical path, and a ground-potential measurement optical path. The sensing optical path comprises a BZN ceramic, an electro-optical crystal, a quarter-wave plate, and a white screen. The measurement optical path comprises a collimating beam expander and a radial polarization grating. The type II self-parametric down-conversion polarization-entangled photon source outputs two polarization-entangled photons. One photon enters the high-potential sensing optical path and sequentially passes through the BZN ceramic, the electro-optical crystal, and the quarter-wave plate before annihilating on the white screen. The other photon enters the ground-potential measurement optical path, passes through the collimating beam expander to form spatial light, and then passes through a radial polarization grating for polarization analysis. The electro-optical phase delay is converted into a synchronous translation of a fixed light spot. By using an image sensor to position the light spot, direct linear measurement of the electro-optical phase delay can be achieved, thereby obtaining a voltage to be measured. The present invention overcomes the problems of optical power dependence, nonlinear measurement, and the inherent half-wave voltage of the crystal that limits the measurement range and sensitivity of Pockels effect optical voltage sensors.

The invention provides a laser processing device which is applied to the technical field of laser processing and comprises the steps that light intensity reinforcement is conducted on a weak light area of a first light beam through a target radial polarized light beam, and the problem that in the prior art, due to the fact that a single first light beam is used for through hole processing, laser energy is weakened along with the increase of the processing depth due to the existence of a light intensity area is avoided; and the light intensity area cannot effectively etch the processing target of the to-be-processed piece in the direction of the outlet hole area, so that the shapes of the inlet hole and the outlet hole of laser through hole processing can be kept consistent, and the side wall perpendicularity deviation is reduced.

The invention discloses a dynamic vector vortex beam generation method based on liquid crystal and metasurface regulation and control, and belongs to the field of micro-nano optics. According to the dynamic vector vortex beam generation method based on liquid crystal and metasurface regulation and control, vortex light with spiral phase distribution is generated based on a metasurface, the metasurface and nematic phase liquid crystal are cascaded, an external electric field of the nematic phase liquid crystal is dynamically changed, then the deflection angle of a nematic phase liquid crystal molecule director is changed, and the dynamic vector vortex beam is generated. And obtaining the nematic-phase liquid crystal with corresponding turning direction. The light beam is jointly regulated and controlled through the metasurface and the nematic phase liquid crystal in the corresponding turning direction, and the dynamic vector vortex light beam is generated after regulation and control. By introducing the liquid crystal, flexible dynamic regulation and control of orbital angular momentum can be realized through an external electric field, the limitation of fixation of a traditional metasurface device is overcome, dynamic vector vortex light beams with spatial non-uniform polarization distribution such as radial polarization and angular polarization are generated, more complex light field control can be supported, and the method is suitable for large-scale popularization and application. And multi-scene requirements are met.

The invention relates to the technical field of optics, and discloses a device and a method for generating a vector warping Hermitian correlated light beam, and the device comprises a first beam splitter, a spatial light modulator, a light source branch and a reflection branch. The reflection branch comprises a first lens, a diaphragm, a second lens and a radial polarization conversion sheet which are arranged in sequence, the spatial light modulator is used for modulating transmission light of the first beam splitter and reflecting the transmission light to the first beam splitter, and the first beam splitter reflects a light beam reflected by the spatial light modulator to the reflection branch to obtain a vector distortion Hermitian correlation light beam. According to the scheme, the stable and accurate vector distortion Hermitian correlation light beam can be obtained, the light beam integrates the characteristics of vector polarization, distortion phase, a special correlation structure and the like at the same time, has high turbulence resistance and is a good carrier for free space optical communication, the generation method is simple, the generation device is concise, and the production cost is low. And the measurement of the Stokes parameter of the light beam can be realized at the same time.

The present invention relates to a polarization-entangled photon current sensor, comprising an all-fiber polarization-entangled photon source, a high-potential sensing optical path, and a low-potential measuring optical path; the high-potential sensing optical path comprises an air-core photonic crystal fiber, a magnetic collecting ring, and a white screen; the low-potential measuring optical path comprises a collimating beam expander and a radial polarization grating; the all-fiber polarization-entangled photon source outputs two polarization-entangled photons, one of which enters the sensing optical path, passes through the air-core photonic crystal fiber, the light hole on the magnetic collecting ring, and the magneto-optical film, and is annihilated on the white screen; the other photon enters the measuring optical path, forms spatial light through the collimating beam expander, and then passes through the radial polarization grating for polarization analysis, converting the Faraday rotation angle into a synchronous translation of a fixed light spot. The light spot is positioned using an image sensor to obtain the Faraday rotation angle, thereby obtaining the current to be measured.

The application provides a linear measurement all-fiber current sensor, linearly polarized light is obtained through a polarizer, and is divided into two mutually orthogonal linearly polarized lights, and is further converted into left-handed and right-handed circularly polarized light to input a sensing optical fiber, a Faraday magneto-optic effect of current is used to make the two circularly polarized lights have a phase difference, the circularly polarized light is reflected by a mirror at the end of the sensing optical fiber, and then the phase difference is doubled through the sensing optical fiber, and the circularly polarized light is combined into a linearly polarized light through a λ / 4 wave plate, a modulator secondary phase modulation and a 45° fusion splice point, meanwhile, the phase difference of the circularly polarized light is converted into the rotation of the linearly polarized light polarization plane, and the rotation of the linearly polarized light polarization plane is converted into the synchronous translation of a light spot through a coupler, a beam expander and a radial polarization grating, and the phase difference is obtained by positioning the light spot through an image sensor; the application realizes linear demodulation of a Faraday magneto-optic rotation angle, has the advantages of being irrelevant to the measurement result and optical power, being beneficial to the separation compensation of linear birefringence, realizing non-distortion harmonic measurement and the like.

The invention discloses a pipeline internal penetrating type rotating eddy current array detection device and method. The pipeline internal penetrating type rotating eddy current array detection device comprises a mounting part, an alternating current power supply assembly, a detection coil and two excitation coils, the two excitation coils are wound on the mounting part, the winding axes of the two excitation coils are overlapped, and the two excitation coils are sequentially arranged along the winding axes; the alternating current power supply assembly is electrically connected with the two exciting coils and enables the current flow directions of the two exciting coils to be opposite; the detection coil is arranged on the installation part and located between the two excitation coils. In the scheme, the direction of the radial polarization magnetic field is perpendicular to the surface of the pipe wall all the time, and the optimal excitation condition of the eddy current skin effect is met; and the rotating eddy current field generated by induction has omnidirectional sensitivity, and no matter which angle is formed between the defect trend and the moving direction of the probe, a remarkable eddy current disturbance signal can be generated, so that the universal detection of circumferential, axial and oblique defects is realized, the missing detection is avoided, and the defect detection accuracy is improved.

The present invention discloses a lattice structured light illumination microscope based on three-beam interference and its implementation method. The present invention controls the hexagonal lattice pattern formed by the beam modulation system so that the diffracted light after phase modulation passes through a spatial mask, retaining only three beams of +1 or three beams of ‑1 order diffracted light. The fast axis direction of each area of ​​the polarization modulator is different, and the polarization state of each diffracted beam is independently adjusted. The polarization state of each diffracted light beam is radial polarization, and the interference pattern irradiated on the sample is a hexagonal lattice pattern, which enhances the amplitude of high-frequency information. An adaptive compensation filter is used for the spectrum of the SIM image to effectively reduce artifacts caused by severe background in the SIM reconstructed image. While ensuring the expansion of isotropic resolution, the redundancy of the collected information is reduced, the phototoxicity is reduced, and the imaging time of the sample is extended.

The invention relates to a pump enhanced optical parametric oscillator based on a monolithic cavity PPLN crystal, a vortex light generation method and application. The pump enhanced optical parametric oscillator comprises a pump laser, a matching lens, a half-wave plate, a polarization beam splitter, a quarter-wave plate, a radial polarization converter, the PPLN crystal, a temperature control furnace, a multi-dimensional adjusting frame and a spectroscope. The two end faces of the PPLN crystal are spherical surfaces, the end faces are coated with film layers, and the PPLN crystal serves as an optical parametric oscillation cavity, so that a complex cavity mirror system is omitted; the end face of the PPLN crystal is coated with a film, so that the effect of pumping enhancement is achieved, the threshold value is reduced, the conversion efficiency is improved, meanwhile, the wavelength tuning characteristic is considered, the thermal self-locking effect and the thermal lens effect are utilized, long-time wavelength stability and power stability are achieved, and a complex stable cavity system is omitted; when pump light is converted into vortex light through the S wave plate, orbital angular momentum can be selectively transmitted to idler frequency light or signal light, intermediate infrared or near-infrared vortex light output is achieved, and a miniaturized and portable vortex light generator and multi-field application can be achieved.

The application discloses a kind of radial polarization vector light beam tight gathering light field in near-field enhancement needle tip reverse design method, utilize central axis rotation symmetry, the three-dimensional configuration of circularly symmetric conical needle tip is optimized, is converted into the reverse design of circularly symmetric rotation two-dimensional boundary line shape;With Bernstein polynomial expression two-dimensional boundary streamline relative to the deformation variable of original straight line, the reverse design of circularly symmetric rotation two-dimensional boundary line is converted into optimization finite Bernstein polynomial subterm coefficient;Robust machine learning optimization algorithm is introduced to realize reverse design;Objective function is set as needle tip tip curvature radius corresponding circular arc rotation surface local field intensity average enhancement factor;To suppress the deformation of rotating boundary to appear reverse in optimization process, with maximum deformation variable constraint circularly symmetric rotation two-dimensional boundary streamline, with nonlinear grid smoothing constraint the deformation of adjacent area of boundary line.The application realizes the efficient, customizable optimization design of streamline type near-field enhancement needle tip in specific vector light field.

The invention provides a radial polarization beam splitting metasurface and a synchronous phase shifting method thereof, and relates to the technical field of optical devices. A surface structure arranged on the substrate, wherein the surface structure is formed by a plurality of sub-wavelength structure units in an annular arrangement mode; wherein the sub-wavelength structural units on the same ring have the same rotation angle, and the rotation angles of the sub-wavelength structural units on different rings change along with the radius of the ring, so that different phase modulations can be respectively generated on the left-hand circularly polarized light and the right-hand circularly polarized light of the incident ray polarized light; therefore, the left-handed circularly polarized light or the right-handed circularly polarized light forms a divergent light beam, and the other light beam forms a convergent light beam. According to the invention, through the unique sub-wavelength structure units which are annularly arranged and of which the rotation angles change along with the radius, different phase modulation can be applied to the left-handed and right-handed components of incident ray polarized light, so that divergent and convergent light beams with orthogonal polarization states are efficiently generated, and a foundation is laid for dynamic measurement based on polarization phase shift.

The invention provides an optical voltage transformer for realizing harmonic measurement and a working method thereof. The optical voltage transformer comprises a polarizer, a BGO crystal, a wave plate, a radial polarization grating, an image sensor and a light source emitter. Based on a linear demodulation mode of phase delay, rotation of a polarization plane of linearly polarized light is converted into synchronous translation of a light spot by using a radial polarization grating, and the light spot is positioned by an image sensor to obtain a displacement difference, so that linear measurement of the phase delay is realized. And when the voltage modulation signal contains the harmonic component, the translation amount of the light spot image in the linear demodulation result is the superposition result of the action of the fundamental wave and each harmonic component. And the linear demodulation mode also belongs to a linear time-invariant mode, so that the harmonic measurement capability without distortion is realized. In addition, compensation of thermal stress birefringence is achieved through a square wave difference method, and the temperature drift problem of the optical voltage transformer in harmonic measurement is solved.

A method for manufacturing a radial or azimuthal polarization conversion component comprises the steps of: placing a holographic recording material between two right-angle prisms, wherein the holographic recording material is divided into at least four sector-shaped areas and is partially shielded, and only one of the sector-shaped areas is exposed each time; allowing a recording light to pass through the right-angle prisms and the exposed sector-shaped area of the holographic recording material and to interfere with a reflected object light on the holographic recording material; rotating the holographic recording material to expose the other sector-shaped areas one by one to be constructed for manufacturing volume holograms with diffraction angles of 48.19 degrees, 60 degrees or about 85 degrees.

The invention provides a submicron scale processing device based on adjustable and controllable laser longitudinal energy field proportion, and belongs to the technical field of laser processing, and the submicron scale processing device comprises a laser used for emitting an original laser beam; the vector polarization modulation unit is used for performing vector polarization modulation processing on the original laser beam emitted by the laser and outputting the original laser beam as a radial polarization beam; the energy space distribution modulation unit is used for performing energy distribution modulation on the radial polarized light beam emitted by the vector polarization modulation unit and outputting a radial polarized annular light beam; and the processing unit is used for converging the radially polarized annular light beams emitted from the energy distribution modulation unit. The method has the beneficial effects that vector polarization and energy space distribution modulation are carried out on only one beam of femtosecond laser, so that the femtosecond laser can be directly etched on the surface of any material to reach the submicron scale breaking through the optical diffraction limit.

The application provides a radial polarization splitting metasurface and a synchronous phase-shifting method thereof, and relates to the technical field of optical devices, and comprises a substrate; a surface structure arranged on the substrate, the surface structure is composed of a plurality of sub-wavelength structure units in a ring arrangement mode; wherein the sub-wavelength structure units on the same ring have the same rotation angle, and the rotation angles of the sub-wavelength structure units on different rings change with the radii of the rings, so that different phase modulations can be generated on left-handed circularly polarized light and right-handed circularly polarized light of incident linearly polarized light respectively, so that the left-handed circularly polarized light or the right-handed circularly polarized light forms a divergent light beam, and the other beam forms a convergent light beam. Through the unique ring arrangement and the sub-wavelength structure units with the rotation angle changing with the radius, different phase modulations can be respectively applied to left-handed and right-handed components of incident linearly polarized light, divergent and convergent light beams with orthogonal polarization states are efficiently generated, and a foundation is laid for dynamic measurement based on polarization phase shifting.

During implementation, after a laser emits a light beam, the light beam is expanded through a beam expander, the phase and amplitude of the light beam are adjusted through a spatial light modulator and a 4f filtering unit, and then a distorted Gaussian-Schell model light beam is generated through a cylindrical prism unit; a linear polarization light beam is obtained through a polarizer, so that twisted part coherent polarized light is obtained; and then, the twisted part coherent polarized light passes through a first radial polarization converter to generate a twisted part coherent radial polarized light beam, then the twisted part coherent radial polarized light beam is recovered into linear polarized light orthogonal to the initial polarization direction through a focusing lens and a second radial polarization converter, and finally orthogonal filtering is realized through a polarization analyzer. According to the scheme of the invention, the polarization of the signal light is regulated and controlled, so that the signal light and the stray light are distinguished on the focal plane; through the effect of the optical polaroid, optical signals can be efficiently processed, stray light in a full-wave band range can be suppressed, the stability and quality of signal transmission are improved, and the optical fiber is particularly suitable for optical communication and optical detection in a complex environment. Besides, according to the scheme, the light source coherence degree is low, the crosstalk effect caused by coherence can be eliminated, the good application prospect is achieved in the communication field, and the very high practical value is achieved.

The application discloses a method for generating a radially polarized high-order twisted non-uniform correlation light beam, and the method comprises the following steps: step 1, setting a weight matrix and a kernel function; step 2, obtaining a light beam cross-spectral density matrix element by integrating the weight matrix element and the kernel function; step 3, determining a restriction condition of a twist factor; step 4, setting a restriction condition of a light beam polarization state satisfying radial polarization; and step 5, determining a cross-spectral density matrix element of the radially polarized high-order twisted non-uniform correlation light beam according to the restriction conditions of the light beam twist factor and the polarization state satisfying radial polarization. The application enriches the partial coherent vector beam regulation method and provides a novel light field model with application value for the fields of optical micro-manipulation and anti-depolarization optical communication.

The application discloses a radial polarization twisted partially coherent hyperbolic cosine beam generating system and method, wherein the semiconductor laser is used for emitting a light beam, the light beam is expanded through a beam expander, reflected to a spatial light modulator through a mirror, and the phase and amplitude of the light beam are adjusted through the spatial light modulator and a 4f filter unit; the light beam obtains linear polarization property through a polarizer, so that twisted partially coherent polarized light is obtained; the twisted partially coherent polarized light generates twisted partially coherent radial polarization light beams through a vortex wave plate, is focused through a focusing lens, and finally realizes filtering through a polarizing detector; finally, the focused light beam is collected and observed by a charge coupled device. The application provides a radial polarization twisted partially coherent hyperbolic cosine light source generating system, the optical path structure is relatively simple, the construction and debugging are difficult and the repeatability is high, the phase distribution and correlation structure of the light field can be flexibly adjusted through the spatial light modulator.

This invention relates to an AC zero-crossing compensation method for stress line birefringence in an optical current sensor. The optical current sensor includes a laser source, a polarizer, a magneto-optical thin film, and a radial polarization grating arranged sequentially on the same optical path. The method includes the following steps: emitting an optical signal using the laser source, which passes sequentially through the polarizer, the magneto-optical thin film, and the radial polarization grating. Under the influence of the current to be measured, the output signal is superimposed with the Faraday magnetostrictive rotation angle α and the stress line birefringence γ, forming a translated strip-shaped light spot; locating the position of the strip-shaped light spot using a position-sensitive detector and measuring the rotation angle of the polarization plane of the linearly polarized light; detecting the AC zero-crossing point of the current to be measured, and acquiring the rotation angle of the polarization plane measured by the position-sensitive detector at the zero-crossing point as the stress line birefringence γ; and compensating the output signal of the optical current sensor using the acquired stress line birefringence γ.