36 results about "Acousto-optic modulator" patented technology

The application discloses a vortex light interference device and method for measuring three-dimensional vibration and sound field rotation characteristics, wherein a helium-neon laser emits laser light, the laser light passes through a half-wave plate and a first polarization beam splitter prism, and is divided into object light and reference light; the object light passes through a first spiral phase plate and becomes vortex object light, the vortex object light passes through a second polarization beam splitter prism, a quarter-wave plate, and a beam expander lens, and is irradiated on a test sample surface, reflected light of the sample surface passes through the beam expander lens, the quarter-wave plate, the second polarization beam splitter prism, a beam splitter prism and a focusing lens, and is irradiated on a photodetector; the reference light passes through an acousto-optic modulator to generate frequency modulation, passes through a mirror and a second spiral phase plate to become frequency-modulated vortex light, and the vortex light passes through a beam splitter prism and a focusing lens and is irradiated on the photodetector; a computer calculates and demodulates frequency-modulated signals of the photodetector and modulation signals of the acousto-optic modulator, and finally obtains three-dimensional vibration information and sound field rotation characteristics of the sample.

The application provides a distributed optical fiber acoustic wave sensing system and a pattern recognition method. The application relates to the fields of optical fiber sensing and pattern recognition, and the system comprises the following steps: continuous coherent light emitted by a narrow-line-width laser is split into two paths by a beam splitting fiber coupler, one path is used as local reference light, and the other path is used as probe light; the probe light is modulated into optical pulses in an acousto-optic modulator driven by a waveform generator, and the optical pulses are injected into a measured sensing optical fiber through a fiber loop; Rayleigh backscattering light returned through the measured sensing optical fiber is mixed with the local reference light through the fiber loop, and the mixed light is decomposed into two orthogonal polarized light beams in a polarization beam splitter and is transmitted to a first balanced photodetector and a second balanced photodetector respectively to be converted into electrical signals; and the two orthogonal interference electrical signals are synchronously collected by a data acquisition card and are sent to a host computer for demodulation. The application provides a new distributed acoustic wave monitoring method with high reliability and high generalization ability, and has extremely high engineering popularization value.

The application relates to a polarization holographic multiplexing display system and method based on an acousto-optic modulator, wherein a beam splitter is arranged in front of a spatial light modulator; a laser, a first linear polarizer and the beam splitter are sequentially arranged on an optical path of the laser; a first lens, a pinhole, a second lens and a first polarization grating are sequentially arranged on a reflection optical path of the beam splitter; four circularly polarized lights are arranged behind the first polarization grating; a reflecting mirror, an acousto-optic modulator, a third lens and an image sensor are sequentially arranged on an optical path of a first light beam; a second polarization grating, a second linear polarizer and an image sensor are sequentially arranged on optical paths of a second light beam, a third light beam and a fourth light beam. The application can obtain three kinds of reconstructed images with different effects at different reconstruction distances, and has a good application prospect in the fields of holographic display, holographic storage and the like.

The application relates to the technical field of adjusting devices, and provides an adjusting device and a laser drilling machine. The adjusting device comprises a supporting seat, a sliding seat and a first adjusting assembly. The supporting seat is provided with a first inclined surface. The sliding seat is provided with a second inclined surface which is in sliding fit with the first inclined surface. An adapter for connecting an acousto-optic modulator is arranged on the sliding seat. The first adjusting assembly is connected to the supporting seat. The first adjusting assembly is configured to drive the sliding seat to move along the inclined direction of the first inclined surface. The adjusting device provided by the application can meet the requirement of accurate adjustment of the acousto-optic modulator.

A fiber optic collimator, an acousto-optic modulator, and a method for correcting the first-order diffraction deviator of the acousto-optic modulator are provided. The fiber optic collimator includes a first sleeve, a first collimating lens, and a first capillary. The first capillary is disposed and encapsulated within the first sleeve, and is radially offset relative to the principal optical axis of the first collimating lens, such that the light beam emitted from the first optical fiber held by the first capillary, after passing through the first collimating lens, forms a Bragg angle with the normal to the light-transmitting surface of the acousto-optic crystal of the adapted acousto-optic modulator. The acousto-optic modulator includes a housing, an inlet glass tube, an outlet glass tube, an acousto-optic crystal, an acousto-optic transducer, an inlet fiber optic collimator, and an outlet fiber optic collimator. The inlet glass tube and the outlet glass tube are located on the same axis of the housing. The inlet fiber optic collimator is the aforementioned fiber optic collimator. In the method for correcting the first-order diffraction deviator of the acousto-optic modulator, the acousto-optic modulator is the aforementioned acousto-optic modulator.

The application discloses a laser phase noise measurement method based on delay self-heterodyne and digital demodulation, and relates to the technical field of laser measurement, and comprises the following contents: after being adjusted by a variable optical attenuator, to-be-measured laser is divided into a frequency shift arm and a delay arm, the frequency shift arm is frequency-shifted by an acousto-optic modulator, the delay arm is delayed by a delay optical fiber, and original electric beat frequency signals are obtained by a balanced photoelectric detector after the two arms are coupled; homologous and synchronous quadrature demodulation is carried out on the original electric beat frequency signals, envelope credibility judgment and abnormal sample repair are combined, and a continuous differential phase sequence is obtained; actual optical time delay is determined according to the beat frequency spectrum characteristics and the continuous differential phase sequence, and a differential phase power spectral density is formed; then, transmission relationship conversion is carried out according to the actual optical time delay, bounded spectrum compensation is implemented on a zero point neighborhood and a low credibility frequency point, and an intrinsic phase noise power spectral density is obtained. The application can improve the stability, continuity and result credibility of phase noise measurement under the condition of short delay.

The application discloses a kind of multi-spot collaborative laser shock peening equipment and method, including sequentially arranged main laser, main galvanometer, diffractive beam splitting device DOE, acousto-optic modulator AOM, MEMS galvanometer, light splitting and combining mirror, field lens along laser transmission optical path, and the CCD camera, robot and workbench of cooperative work;The application is divided into multiple beam sub-laser by diffractive beam splitting device DOE, each sub-laser is regulated by power through each independent acousto-optic modulator AOM, each independent MEMS galvanometer regulates angle, and the sub-laser after regulation and CCD camera optical path are coaxial by light splitting and combining mirror, whether to hit deviation is judged by CCD camera, and the three are coordinated to make multiple beam sub-laser collaborative processing complex surface, avoid the position of traditional single beam laser inconveniently processing complex surface, especially recess, improve processing efficiency and precision.

This invention discloses a wavelength division multiplexing (WDM) trapping device and a method for measuring extremely weak forces in a single-beam vacuum optical trap. A fiber laser emits a laser beam, which passes sequentially along the fiber through a fiber acousto-optic modulator, a fiber beam splitter, and a 1064nm fiber collimator to obtain beam A. Beam A is transmitted through a dichroic mirror into a vacuum cavity, trapping and detecting micro / nano particles. Beams B, C, and D, obtained through multiple fiber beam splitters, a PPLN waveguide frequency doubling module, a fiber electro-optic modulator, and a 532nm fiber collimator, sequentially enter the vacuum cavity to triaxially cool the micro / nano particles in a vacuum environment. At this point, the micro / nano particles are in a stable state. A voltage is applied to the electrode plate, reducing the intensity of beam A, ultimately achieving a balance between electric field force and gravity. The electric field force is then used as the measurement value for the gravity of the micro / nano particles. This invention employs a wavelength division multiplexing method, achieving triaxial cooling, trapping, and detection with only one light source, and using optical fiber to replace most optical components, resulting in greater integration.

The application discloses an environmentally-friendly chalcogenide glass material with excellent acousto-optic characteristics and application thereof. The chemical composition of the chalcogenide glass material is Ga x Sn y Se 100‑x‑y‑z Te z , wherein x, y and z are molar fractions of Ga, Sn and Te respectively, x = 5-10, y = 15-20, and z = 3-7. The chalcogenide glass material contains stable [GaTe n Se 4‑n ] and [SnTe n Se 4‑n ] tetrahedral structures in the micro-network structure. The value of n is 0, 1, 2, 3 or 4. The chalcogenide glass material can be applied to the acousto-optic field as an acousto-optic medium. The chalcogenide glass material has excellent comprehensive performance, remarkable environmental-friendly characteristics, low cost advantage, good mechanical processing performance and optical stability in a variable temperature environment, and provides an ideal material for low-cost and large-scale manufacturing of high-performance acousto-optic devices such as acousto-optic modulators and deflectors.

An Acousto Optic Modulator Device 1 that comprises an Acousto Optic Modulator (AOM) providing an optical path therethrough, having a first optical port 4’ and a second optical port 4’’; a mirror 5 arr

This utility model provides a miniature ground-based laser wind measuring radar, including a base and a compact housing disposed on the upper part of the base. The base is characterized by the following features: a first wind duct module and a second wind duct module are symmetrically arranged on its upper part; an acousto-optic modulator and an optical transceiver are integrated on the side of the first wind duct module away from the second wind duct module, while a data acquisition card is integrated on the side closer to the second wind duct module; an industrial control computer motherboard and communication components are integrated on the side of the second wind duct module away from the first wind duct module, while a power supply component is integrated on the side closer to the first wind duct module; a lens mount is mounted on the upper part between the first and second wind duct modules, and a laser radar lens assembly is installed on the lens mount, the laser radar lens assembly being compactly integrated between the first and second wind duct modules. This utility model relates to the field of laser wind measuring radar technology.

A metrology system including a heterodyne light source is provided. The heterodyne light source includes a first light source, an acousto-optic modulator, and source optics. The acousto-optic modulator receives at least one wavelength laser beam from the first light source and generates at least one corresponding frequency-shifted laser beam (e.g., having orthogonal polarization). The source optics include a receiving optical element portion and a birefringent optical element portion. The receiving optical element portion receives the wavelength laser beam and the corresponding frequency-shifted laser beam and directs the beams along an optical path toward the birefringent optical element portion. The birefringent optical element portion combines the beams to output a combined beam (e.g., which can be used as part of a measurement process to determine at least one measured distance to at least one surface point on a workpiece, etc.).

A fiberized acousto-optic device for shifting a frequency of light, comprising: a first optical fiber section that is configured to receive light; a fiber beam splitter (3) connected to the first optical fiber section (2a); a second optical fiber section (2b) connected to the fiber beam splitter (3); an acousto-optic modulator (5) which is optically coupled the second optical fiber section (2b) and is configured to shift a frequency of at least a portion of the light, thereby producing shifted light (SL); a retroreflector (7) optically coupled to the acousto-optic modulator (5) and configured to receive the shifted light (SL) and reflect at least part of it back to the acousto-optic modulator (5) which is further configured to transmit at least part of the reflected light towards the second fiber section; a third optical fiber section (2c) connected to the fiber beam splitter (3).

The embodiment of the application provides a kind of distributed optical fiber sensing system based on set sparse frequency sequence pulse light time domain reflection technology, it is related to optical fiber sensing technical field, including electro-optic modulator, laser frequency modulation module, line width compression module and optical fiber sensing module;The input end of electro-optic modulator is connected with light source, laser frequency modulation module includes fiber coupler and double parallel Mach-Zehnder modulator, the first input end of fiber coupler and the output end of electro-optic modulator are connected, the first output end of fiber coupler and the input end of double parallel Mach-Zehnder modulator are connected, the output end of double parallel Mach-Zehnder modulator and the second input end of fiber coupler are connected;The input end of line width compression module and the second output end of fiber coupler are connected;The output end of line width compression module is connected with the input end of acoustooptic modulator of optical fiber sensing module, to make that the spatial resolution, detection distance and frequency band width etc. Parameters of distributed optical fiber sensing system simultaneously have higher performance.

The application discloses a device for rapidly shutting off cold atom loading, comprising a laser light source, laser light emitted by the laser light source sequentially passing through an acousto-optic modulator, a collimating lens and a first reflector to serve as forward incident laser light input into a control cavity, the forward incident laser light sequentially passing through a light transmission opening in the center of a first light transmission surface and a light transmission opening in the center of a second light transmission surface on the control cavity and being reflected by a second reflector outside the control cavity. The application also discloses a method for rapidly shutting off cold atom loading, which is used for real-time and accurate control of atom beam loading according to different atom loading requirements. The application can compress the divergence angle to enhance the atom beam flow intensity, improve the atom loading number, and make the near-resonance laser interact with the atom beam flow at a specific angle by slightly adjusting the angles of two reflectors to realize the shutting off of the atom loading. The application can also control the light field intensity and detuning by selecting an external control signal of the acousto-optic modulator to continuously and quantitatively control the atom loading.

This invention relates to the field of fiber optic sensing technology, specifically to a dual Mach-Zehnder fiber optic sensing optical path, a discharge localization method, and an apparatus. The optical path includes: a first optical coupler; a second optical coupler for splitting a first light beam into a first reference beam and a first sensing beam; a third optical coupler for splitting a second light beam into a second reference beam and a second sensing beam; a first acousto-optic modulator for applying a first offset frequency to the first and second reference beams respectively, obtaining a first offset reference beam and a second offset reference beam; and a second acousto-optic modulator for applying a second offset frequency to the first and second sensing beams respectively, obtaining a first offset sensing beam and a second offset sensing beam; wherein the first offset frequency and the second offset frequency are not equal. This invention effectively improves the detection capability and signal demodulation quality of distributed fiber optic sensing systems for weak signals.

Embodiments of the present application disclose a laser cutting system and method, equipment and storage medium. The system comprises a transmitting module, an acousto-optic modulator, a frequency doubling module and an output module. The transmitting module is configured to transmit an initial laser beam to the acousto-optic modulator. The acousto-optic modulator is configured to, in a first working mode, process the received initial laser beam to output a zero-order beam and a first-order diffraction beam, or, in a second working mode, output the received initial laser beam. The frequency doubling module is configured to, in the case of receiving the first-order diffraction beam, increase the frequency of the first-order diffraction beam to obtain a frequency-doubled beam, and output the frequency-doubled beam to the output module. The output module is configured to output the received target beam to cut a target cutting region of a target workpiece. Different frequency or power laser beams can be output based on a single transmitting module, thereby improving cutting quality and workpiece manufacturing quality.

The application discloses a low-repetition-frequency optical fiber laser amplifier pump light time-sharing and light-splitting device. The device comprises a pump source, a fiber acousto-optic modulator, a plurality of laser systems and a control unit. The pump source is used for generating pump light; the fiber acousto-optic modulator is connected with the output end of the pump source and is used for receiving the pump light and realizing time-sharing and light-splitting; the plurality of laser systems are respectively connected with the light-splitting output ends of the fiber acousto-optic modulator to form respective light-splitting branches and are used for receiving time-sharing pump light and performing laser amplification; and the control unit is connected with the fiber acousto-optic modulator and is used for controlling the time-sharing and light-splitting operation of the fiber acousto-optic modulator according to a preset time sequence. The device structure in the technical scheme of the application is relatively simple, easy to realize and integrate, the pump light is time-shared and light-split by the acousto-optic modulator, the ASE during the fiber laser amplification can be obviously inhibited, the beam quality and power stability of the laser output are improved, and the reasonable distribution and efficient utilization of the pump light in the plurality of laser systems can be realized.

The present application relates to a kind of near-field optical super-resolution carrier dynamics imaging system, wherein probe light is shot into near-field optical scanning microscope system by probe beam expander component and probe attenuator component, pump light is sequentially shot into near-field optical scanning microscope system by pump beam expander component, pump attenuator component, pump light delay component and acoustooptic modulator component, near-field optical scanning microscope system includes upper objective lens, scanning probe, sample support, lower objective lens, near-field beam splitter, near-field filter component and convex lens in the direction of probe light path in turn, pump light is focused on sample after being reflected by near-field beam splitter and forming the path direction opposite to probe light and being shot into lower objective lens, probe light is shot out by convex lens and input into lock-in amplifier by fiber coupler and photomultiplier tube.The present application combines near-field optical super-resolution imaging technology with femtosecond transient absorption spectroscopy technology, and realizes the high space-time resolution visual detection of microcosmic carrier dynamics.

This invention discloses a stabilized optical clock system and its implementation method based on a dual-microcavity optical comb and two-photon transitions. The system includes a microcavity optical comb section, a locking section, and a photodetector. The microcavity optical comb section contains two SiO2 microchip ring cavity optical comb oscillators, with center wavelengths matched to the two-photon transition lines of rubidium and cesium atoms, respectively. The locking section provides an atomic reference frequency through a two-photon transition generator, and combines a six-way phase-locked loop, an acousto-optic modulator, and a phase modulator to achieve initial frequency locking of the optical comb, interlocking of the repetition frequency, and suppression of thermally induced detuning. The photodetector converts the stabilized optical comb repetition frequency into an RF frequency standard output. This invention solves the problems of complex system design, large integrated size, cumbersome locking structure, and wavelength mismatch in existing ultra-high frequency stabilized atomic clock technologies.

This application relates to a method and apparatus for detecting microcracks inside a wafer. The detection method includes: acquiring a detection laser; acquiring wafer surface thickness information; adjusting the focal position of the detection laser so that the focal point is aligned with a local central plane of the wafer to perform axial selective thermal excitation on the wafer; acquiring a polarization difference image; performing phase-locked demodulation on the polarization difference image to extract the phase information of the thermal radiation signal; sequentially performing axial selective thermal excitation using at least two different modulation frequencies f and acquiring the corresponding phase signals; inverting the microcrack depth d based on the phase signals; and determining the location of the microcrack on the wafer based on the microcrack depth d. The detection apparatus includes a laser emitter, a polarization converter, and an acousto-optic modulator arranged sequentially along the optical path; a dichroic mirror and an infrared camera; and a signal processing module for processing the acquired signals to obtain the location of the microcrack on the wafer. This invention can determine the location of microcracks.

This invention discloses an ultra-high stability laser system based on dual-path independent composite frequency stabilization and sum-frequency modulation, belonging to the field of precision laser spectroscopy and frequency control technology. The system includes two seed lasers (1560 nm and 1064 nm), a dual-wavelength common-cavity ultra-stable module, two acousto-optic frequency shift and dual-reference absolute frequency stabilization modules, and a nonlinear sum-frequency modulation (SFG) module. Full-time-scale frequency noise suppression is achieved through a three-stage cascaded closed loop consisting of a MHz fast loop, a kHz slow loop, and a Hz extremely slow loop. An acousto-optic modulator is placed in the sampling optical path fed into the ultra-stable cavity, and physical decoupling of the fast and slow loops is achieved through radio frequency bridging. The extremely low-frequency error signal detected by NICE-OHMS is fed back to the PPMgOLN crystal temperature or AOM driving frequency to compensate for the thermally induced drift of the nonlinear crystal. The system ultimately outputs a 633 nm laser power of not less than 50 mW, with a short-term frequency instability better than 5 × 10⁻⁶ mW. ‑15 @1 s.

Systems and methods for optical computation and acousto-optic modulation are described. The systems and methods comprise acousto-optic modulators with reflectors and transducers used for actuation and modulation of mechanical waves. The systems further comprise multilayer optical computing systems incorporating arrays of acousto-optic modulators. In an embodiment, the acousto-optic modulator comprises a substrate; an optical layer coupled to a first portion of the substrate, the optical layer comprising: a free-standing portion shaped and positioned to define a gap between the free-standing portion of the optical layer and the substrate; and a rib waveguide comprising a photonic crystal, formed in the free-standing portion; and a piezoelectric transducer mechanically coupled to the free-standing portion, wherein the piezoelectric transducer comprises a piezoelectric material and a plurality of conductive electrodes disposed in electrically conductive contact with the piezoelectric material, the plurality of conductive electrodes extending from a base portion of the piezoelectric transducer.

The present application relates to a kind of wafer detection signal variable sampling collection methods and wafer defect detection system based on acoustooptic modulator synchronous control, comprising: based on wafer defect detection system parameter, planning full wafer scanning sampling rate;Configuration scanning motion parameter;According to scanning motion parameter and full wafer scanning sampling rate, actual sampling rate signal is generated and is sent to signal acquisition card;Signal acquisition card receives actual sampling rate signal, synchronously controls acoustooptic modulator AOM and photodetector, collects the photoelectric signal corresponding to wafer surface scattered light, obtains original sampling data;Signal acquisition card carries out interpolation processing to original sampling data, so that the corresponding sampling point density of wafer is same under the same rotation scanning stroke;And to the image data after interpolation processing carries out defect algorithm analysis, to identify and detect the defect on wafer surface.The present application solves the contradiction between incident light power and wafer surface damage threshold, realizes the synchronous regulation between laser light power and sampling rate.

The utility model relates to optical fiber acoustooptic modulator, concretely relates to an integrated polarization maintaining optical fiber acoustooptic modulator, in the patent scheme of this integrated polarization maintaining optical fiber acoustooptic modulator, including acoustooptic modulator and driver, acoustooptic modulator and driver set up in same shell, shell includes upper casing, lower casing and side casing, acoustooptic modulator and driver are fixed on the lower casing, and acoustooptic modulator is connected with driver through metal wire drive. This through the integrated scheme of acoustooptic converter and driver in a shell becomes a whole, makes optical fiber acoustooptic modulator have more compact, the higher advantage of integrity, when using, need not with radio frequency coaxial connecting line to connect acoustooptic converter and driver, only need to install good shell and connect relevant interface can use.

The application discloses a kind of all-fiber 4-5 μm waveband femtosecond pulse frequency selection devices, comprising: mid-infrared femtosecond laser source, for generating high repetition rate femtosecond pulse sequence;Acousto-optic modulator unit, including acousto-optic medium, piezoelectric transducer bonded on acousto-optic medium and the input tail fiber and output tail fiber integrated with acousto-optic medium, acousto-optic medium, input tail fiber and output tail fiber are made of chalcogenide glass material with transmission range covering 4-5 μm waveband, the output fiber of mid-infrared femtosecond laser source is low-loss fusion with input tail fiber;Radio frequency drive and synchronous control unit, for generating modulated radio frequency signal to drive acousto-optic modulator unit to selectively diffract femtosecond pulse.The device can realize high diffraction efficiency under very low driving power, and make the system have the advantages of compact structure, simplified installation and adjustment, high stability, strong anti-interference ability, easy to integrate and suitable for industrial field and long-term continuous operation.

The application discloses a dark field confocal microscopic measuring device and method based on circular dichroism, which comprises a circular dichroism light beam generating module, a ring light generating module, a light beam scanning illumination module and a dark field confocal detection module; linearly polarized light is incident on a polarization grating to simultaneously generate first polarized light and second polarized light, and an acousto-optic modulator is controlled to modulate the light beam into a pulse form to realize that the polarized light alternately performs illumination in the same period. The light beam is modulated into a ring illumination light beam via a cone lens group, and a complementary aperture stop is utilized to collect scattering signals, and the collected scattering signals of the first polarized light and the second polarized light are differentiated. Direct analysis of the scattering signals in a single polarization state can extract three-dimensional distribution information of defects such as surface scratches, abrasions and subsurface cracks, bubbles and the like; analysis of the scattering signal difference under illumination of left-handed and right-handed ring light can obtain optical chirality information of micro-nano structure materials, and the sensitivity of chirality detection is improved.

This invention discloses a high-stability microcavity optical comb generation device and method. The device includes a pump laser, a source locking module, a repetition rate locking module, an optical comb optical system, and a microcavity control system. The pump laser provides the pump laser for the microcavity optical comb, with one path connected to the source locking module and the other path connected to the repetition rate locking module. The source locking module locks the pump frequency of the pump laser, and the repetition rate locking module locks the repetition rate of the microcavity optical comb. The optical comb optical system splits the laser, with one path connected to the microcavity control system and the other path connected to an acousto-optic modulator. The acousto-optic modulator shifts the laser frequency to generate first-order diffracted light, and the output of the acousto-optic modulator is connected to the microcavity control system. The microcavity control system includes a microcavity chip and a temperature control unit. The temperature control unit is used to control the microcavity chip to generate the microcavity optical comb through temperature regulation. This invention can generate an optical comb that can operate reliably and stably for a long time and has a simple structure that is easy to debug.