174 results about "Fast axis" patented technology

Provided are: an optical laminate which uses a biaxially stretched polyethylene terephthalate film as a base material, has bending resistance, and in which iris irregularities are suppressed; and an image display device which uses the optical laminate. This optical laminate is used in an image display device, and is provided with: a light-transmitting base material which is formed from a biaxially stretched polyethylene terephthalate film and which has in-plane birefringence; and an optical functional layer provided on one surface of the light-transmitting substrate, the arithmetic average roughness Ra of the surface of the optical functional layer being 0.04 [mu] m or more, the average inclination angle [theta] a of unevenness present on the surface of the optical functional layer being 0.30 DEG or more, and the in-plane retardation Re of the light-transmitting substrate defined by formula (1): Re = (nx-ny) * d being 2,000 nm to 7500 nm (inclusive). Here, nx is the refractive index in the slow axis direction, ny is the refractive index in the in-phase axis direction, and d is the thickness of the translucent substrate.

The invention provides a laser radar system, a control method and a control device. The laser radar system comprises a transmitting unit, a first scanning unit and a second scanning unit. And the two scanning units are arranged on the propagation path of the detection light beam emitted by the emitting unit. The first scanning unit performs slow axis scanning on the detection light beam through swinging; and the second scanning unit performs fast axis scanning on the detection light beam through continuous rotation. The scanning period of the second scanning unit comprises a first time period for carrying out idle scanning and a second time period for completing one quick scanning period in the object space. The first scanning unit rotates from one angular position to another angular position in the first time period, and keeps the angular position unchanged in the second time period. The embodiment of the invention can be used for a detection or sensing system of a new energy vehicle or an intelligent driving vehicle, and can improve the speed and distance measurement performance of the laser radar under the condition of adopting the scanning device.

The invention provides a semiconductor side pump module and a laser, and relates to the technical field of semiconductor lasers. The semiconductor side pump module comprises a light gathering cavity, a cooling pipe is coaxially arranged in a cavity body of the light gathering cavity, a crystal bar is coaxially arranged in the cooling pipe, and the cooling pipe and the crystal bar jointly form a cooling space used for containing cooling liquid. An odd number of pumping units are uniformly distributed on the outer side of the light condensing cavity along the circumferential direction; and each pumping unit comprises a plurality of pumping sources which are uniformly arranged along the axial direction. A slit allowing pump light to enter is formed in the light gathering cavity. And fast axis shaping negative lenses in one-to-one correspondence with the pumping units are arranged on the outer side of the cooling pipe in the cavity. The semiconductor side pump module and the laser provided by the invention can effectively improve the uniformity of light spots.

The invention relates to the technical field of light beam collimation measurement, and discloses an array laser light beam collimation measurement method, device and equipment and a storage medium, and the method comprises the steps: obtaining a light spot image and overall light spot distribution of each array in an array laser, carrying out the cutting of the light spot image based on a light beam bounding box of the light spot image, and obtaining a light beam bounding box of the light spot image; obtaining a pixel value in a light beam bounding box on the light spot image, taking the pixel value as a target image, determining a light spot center position according to a fast axis center and a slow axis center of each target image, and obtaining a light spot image based on the overall light spot distribution diagram, the overall bounding box of the overall light spot distribution diagram, the light spot center position and a preset standard distribution radius. And determining the positions of the offset array elements and the distribution center of the light spots. According to the method, the light spot center position of each light spot image is found through the light spot images, and then the position condition of the deviated array element is determined according to the overall light spot distribution diagram and the light spot distribution center, so that the deviated array element is quickly found, and the subsequent adjustment of the array machine laser is facilitated.

The invention provides an automatic coupling device for a fast-axis beam of a micro-channel laser stack array, and relates to the technical field of semiconductor lasers. The device comprises an optical platform, and the optical platform is provided with a stack array adjusting subassembly, a power-up subassembly, a UV curing subassembly, a lens adjusting subassembly, a dispensing subassembly, a near-field detection subassembly and a far-field detection subassembly. The stack array adjusting part is used for installing the stack array, and the power-up part is used for powering up the stack array. And the UV curing subassembly is used for curing the ultraviolet glue. And the lens adjusting subassembly and the dispensing subassembly are respectively used for adjusting the position of the fast axis collimating lens and dispensing. The SAC lens is arranged on a sliding plate of the dispensing subassembly through a fixing rod, during coupling, laser emitted by the micro-channel laser sequentially passes through the fast axis collimating lens and the SAC lens and then is divided into a far-field light beam and a near-field light beam by the beam splitter prism, the near-field light beam enters the near-field detection subassembly, and the far-field light beam enters the far-field detection subassembly. The device effectively solves the problems of low production efficiency, poor coupling precision and the like in the existing coupling mode.

The present application relates to a scanning device of a laser radar and a method for optimizing the structure of the scanning device. The scanning device includes a substrate, a scanning mirror, a driving ring, a fast axis and a slow axis; at least one of the fast axis and the slow axis is a stress equalization structure, and the stress equalization structure includes a single-axis structure or a dual-axis structure. A driving hole is provided on the substrate, the scanning mirror is connected to the driving ring through the fast axis, the driving ring is connected to the substrate through the slow axis, and the scanning mirror is arranged at the center of the driving ring, which is arranged at the center of the driving hole. The above-mentioned device optimizes the structure of the traditional fast axis or slow axis into a stress equalization structure, so that the deformation mode of the fast axis or slow axis is transformed from a torsional mode to a bending mode, thereby reducing the stress magnitude in the stress concentration area during the cyclic motion process, and keeping the stress away from the fatigue failure stress threshold, thereby greatly improving the durability of the non-silicon scanning mirror and thereby improving the working life of the device.

The application provides a laser etching device and method for large-format and large-size samples, and aims to solve the technical problem that the laser processing mode of linkage of the fast axis and the slow axis of the existing galvanometer causes the non-uniform processing speed of different pattern segments due to the speed difference of the fast axis and the slow axis, and forms the splicing trace with inconsistent response speed when facing complex filled patterns. The laser etching method for large-format and large-size samples provided by the application is realized by the laser etching device for large-format and large-size samples composed of a laser scanning part, a sample movement part, a bracket and a controller, and the method of combining "trajectory decomposition + multi-layer filling" is adopted to realize the laser etching processing without splicing traces, thereby avoiding the splicing trace problem caused by the inconsistent speed response of the traditional linkage system of the fast axis and the slow axis, and ensuring the reliability and consistency of the large-area etching processing.

The invention belongs to the technical field of fiber-optic gyroscopes, and particularly relates to an acceleration-based fiber-optic gyroscope vibration error compensation method and an inertial measurement unit. Based on normal strain, optical fiber dielectric impermeability tensor variable quantity, refractive index variable quantity of light in the fast axis direction and phase variable quantity corresponding to a sensitive axis of an optical fiber gyroscope, quantitative relations between the phase variable quantity and the fast axis direction of the optical fiber and between the phase variable quantity and the length of a micro-section optical fiber are established, and the equivalent value of the stress borne by the optical fiber and the phase difference of an optical fiber ring is obtained; the linear relation between the phase difference equivalent value and the angular velocity to be compensated of the fiber-optic gyroscope is determined, the relation of converting the vibration acceleration to the phase to be compensated is established, and the required compensation coefficient is calibrated by combining a sinusoidal vibration test to compensate the vibration error of the fiber-optic gyroscope. According to the invention, vibration error compensation of the fiber-optic gyroscope can be realized without adding extra devices, and the real-time performance and accuracy of error compensation are improved.

The invention relates to the technical field of image recognition and search, and discloses a surveying and mapping device capable of automatically searching a target, which comprises a base, surveying and mapping equipment is arranged at the top of the base, a searching mechanism is arranged at the top of the surveying and mapping equipment, the searching mechanism comprises a supporting block, and the supporting block is fixedly connected to the front side of the top of the surveying and mapping equipment. A semiconductor laser is installed on the left side of the supporting block, an emission lens is fixedly connected to the right side of the supporting block, and a fixing plate is fixedly connected to the right side of the top of the surveying and mapping device. According to the invention, the transmitting lens is matched with the transmitting cylindrical mirror, an elliptical Gaussian beam emitted by the semiconductor laser is converted into a fan-shaped line light source with uniform energy distribution by adopting a means of combining slow axis collimation and fast axis beam expansion, and a specified search angle is covered; the problems of non-uniform divergence of the infrared light source in the vertical direction and low light energy utilization rate in the prior art are avoided.

The invention discloses an OLED display screen assembly, a streaming media rearview mirror and a processing method.The OLED display screen assembly comprises a base material, an OLED display screen body and a reflective polarizer which are sequentially arranged from inside to outside in the stacking direction; the OLED display screen body comprises an anode layer arranged close to the base material, a cathode layer arranged close to the reflective polaroid and a light-emitting layer arranged between the anode layer and the cathode layer. A 1 / 2 wave plate is arranged on the side, close to the light-emitting layer, of the anode layer, and efficient polarization conversion and recycling of S light reflected by the reflective polaroid can be achieved. When the reflected S light penetrates through the 1 / 2 wave plate twice, the polarization state of the S light is rotated by 90 degrees through the 45-degree fast axis design to be converted into P light, the P light is transmitted in the forward direction after being reflected by the anode layer and finally penetrates through the reflective polaroid, the problem that the S light is repeatedly reflected and absorbed by the reflective polaroid in a traditional framework is solved, the transmittance of visible light on the reflective polaroid is effectively improved, and the service life of the S light is prolonged. And the display brightness of the streaming media rearview mirror is obviously enhanced.

This application discloses a method and related apparatus for obtaining a phase retardation map and a fast axis orientation map of the cornea. The method includes inputting a preset polarization state into a metasurface polarization analyzer to obtain polarization measurement data output by the metasurface polarization analyzer; solving for polarization state matrix parameters based on the polarization measurement data; and decomposing the polarization state matrix parameters to obtain a phase retardation map and a fast axis orientation map of the cornea. Using this application embodiment, subtle microstructural changes in the cornea can be captured with high sensitivity, compensating for the lack of quantitative analysis methods in traditional slit-lamp examinations, while effectively overcoming the problem of insufficient accessibility caused by the large size and high cost of traditional high-end detection equipment.

The invention discloses a perfect vector and scalar vortex beam generation device, a representation device and a representation method, and the perfect vector and scalar vortex beam generation device comprises a light source system which is used for outputting left-handed and right-handed circularly polarized light; the non-polarization beam splitting flat plate is used for splitting the left-handed and right-handed circularly polarized light into transmission generation light paths; the Q wave plate is located on the generation light path; the phase delay system comprises a reflecting mirror IV located on the generation light path and two quarter-wave plates with adjustable fast axis included angles; the light path conversion system comprises a conical lens and a thin convex lens which are located on the generation light path, and the conical lens is close to the non-polarization beam splitting flat plate; the invention provides a low-cost and easy-to-integrate high-quality perfect vector and scalar vortex beam generation and characterization device and a corresponding method, which are used for realizing efficient generation of perfect vector and scalar vortex beams.

The invention relates to a partitioned quarter-wave plate and a design method thereof. The partitioned quarter-wave plate comprises a central through hole and a plurality of polarized light conversion groups surrounding the central through hole, and the design method comprises the following steps: determining a Jones matrix corresponding to a fast axis angle of a conversion region and a Jones vector of an illumination beam according to the fast axis angle of the conversion region, and calculating to obtain a vector of the illumination beam after passing through the conversion region; and making the component of the vector of the illumination beam passing through the conversion area not equal to 0 in the direction perpendicular to the normal and the component equal to 0 in the normal direction, and calculating to obtain the rotating angle of the fast axis relative to the polarization direction. Compared with the prior art, due to the central through hole, a 0-level light beam of circularly polarized light can be still circularly polarized light; + / -1-level light beams of the circularly polarized light penetrate through two conversion areas of the polarized light conversion group to be modulated into s-line polarized light, and the polarization direction of the illumination light beam group is regulated and controlled.

The application discloses a laser shaping module, a projection light source system and a projection device, wherein the laser shaping module comprises a laser device for outputting a laser beam, and the laser beam has different divergence characteristics in a fast axis direction and a slow axis direction; a spherical lens is arranged on the light output side of the laser device; a cylindrical lens module is arranged on the light output side of the spherical lens; the cylindrical lens module has opposite first and second working surfaces along the propagation direction of the laser beam; the cylindrical axis of the first working surface is parallel to the fast axis direction and is used for shaping the laser beam in the slow axis direction; the cylindrical axis of the second working surface is parallel to the slow axis direction and is used for shaping the laser beam in the fast axis direction; and a pump light source is used for receiving the shaped laser beam and is pumped and excited under the action of the laser beam. The application compensates for the difference between the divergence characteristics of the laser beam in the slow axis direction and the fast axis direction by arranging the cylindrical lens module, thereby improving the quality of the pump beam and the pumping efficiency.

A polarizer applied for a viewing side of a display is disclosed. The polarizer comprises a polarizing layer with an absorption axis, and a protective film disposed on the viewing side surface of the polarizing layer. The protective film includes a birefringent substrate adjacent to the polarizing layer having a birefringence difference not greater than 0.10 and having a slow axis and a fast axis perpendicular to each other, wherein the slow axis is parallel to the absorption axis of the polarizing layer, and an interference elimination layer disposed on a display side surface of the birefringent substrate, wherein the interference elimination layer has a diffusing layer disposed on the birefringent substrate, and a refractive-index-matching layer disposed on the diffusing layer, wherein with the total haze of the protective film is between 30% and 75% and the reflectivity of the protective film satisfies the relationship (RSCI−RSCE)≤1.0% and RSCE / (RSCI−RSCE)≥1.6, wherein RSCI is an average reflectivity of diffuse component and specular component (specular component included, SCI) of the protective film, and RSCE is an average reflectivity of diffuse component (specular component excluded, SCE) of the protective film.

The application provides a special mirror ring structure-based interferometric fiber-optic gyroscope, which comprises a light source, a polarizer, a coupler, two loopers, two Y waveguides, a signal generator, a 2-in-2-out mirror fiber ring, two photoelectric detectors and a signal joint demodulation module; wherein the two equal-length polarization maintaining optical fibers of the 2-in-2-out mirror fiber ring are both fused at the middle point with the fast axis at 90 degrees, and when each polarization maintaining optical fiber is fused with the Y waveguide tail fiber, one end is fused with the fast axis at 0 degrees and the other end is fused with the fast axis at 90 degrees. In the fiber-optic gyroscope, the light is no longer sent into two polarization channels of the same fiber ring through a polarization beam splitter and combiner, but is fused with two spatial mirror fiber rings at 0 degrees and 90 degrees through two Y waveguides, so that the radial magnetic field phase error caused by the Faraday effect is suppressed, and the temperature phase error caused by the Shupe effect can be compensated by joint demodulation of the electric signals of the two photoelectric detectors.

The utility model discloses a semiconductor laser device which comprises a pump light module and a shaping assembly. The pump light module is used for outputting a collimated light beam; the shaping assembly is arranged on an output light path of the collimated light beam and comprises a deformation prism and a focus lens which are arranged in sequence. The deformation prism is used for correcting the collimated light beam, so that the sizes of light spots of the collimated light beam in the slow axis direction and the fast axis direction are consistent; and the focusing lens is used for focusing the collimated light beam corrected by the deformation prism and reducing a light beam divergence angle. According to the semiconductor laser device, shaping of the collimated light beam in the fast axis direction or the slow axis direction is achieved by arranging the deformation prism in the light path, the production cost is reduced, and the overall integration degree of the device is improved.

A laser assembly (12) of a system (10) includes a first emitter assembly (30a), a second emitter assembly (30b), and a combiner lens (34). The first emitter assembly (30a) generates a first emitter beam (22a) that is directed along a first emitter axis (32a) at a beam intersection area (31). The second emitter assembly (30b) generates a second emitter beam (22b) that is directed along a second emitter axis (32b) at the beam intersection area (31). The combiner lens (34) receives and spatially combines the first emitter beam (22a) and the second emitter beam (22b) after the emitter beams (22a) (22b) have intersected at and passed through the beam intersection area (31). The laser assembly (12) includes a laser frame (18); an emitter array (20) that generates a plurality of emitter beams (22); a combiner lens assembly (24) that transforms and combines the plurality of emitter beams (22) into the assembly output beam (14); and a system controller (26) that controls the operation of the laser assembly (12). The combiner lens assembly (24) including combiner lenses (34, 36, 38) has a fast axis, front side focal point (24a), and a fast axis and slow axis, rear side focal point (24b). It is positioned so that its fast axis front side focal point (24a) is approximately at the beam intersection area (31). The optical fiber (16) is positioned so that its inlet facet (16A) is approximately at the fast axis and slow axis, rear side focal point (24b).

This invention discloses a spectral beam combining device for a linear array semiconductor laser, comprising: a fast-axis collimating lens, a slow-axis collimating lens, a first cylindrical transmission lens, and a diffraction grating arranged sequentially along the optical axis of the linear array semiconductor laser; a second cylindrical transmission lens and a first concave mirror group arranged sequentially in the direction of the 0th order diffraction beam of the diffraction grating, and a second concave mirror group arranged in the direction of the 1st order diffraction beam, with the -1st order diffracted light of the diffraction grating serving as the output light; the first and second concave mirror groups adjusting their angles according to the "smile" effect of the linear array semiconductor laser, so that the feedback light returns to the corresponding light-emitting unit of the linear array semiconductor laser to form effective feedback; simultaneously, the curved surface of the first concave mirror group along the fast axis direction of the linear array semiconductor laser converges the diverging beam in the fast axis direction, so that the beam is fed back to the original light-emitting unit, improving the feedback efficiency and enabling the light-emitting unit to achieve stable wavelength locking.

The invention concerns collimation optics for an edge emitting laser device configured as a compact integrated unit. The device simultaneously achieves collimation along both the fast axis and the slow axis of the edge emitting laser. The proposed invention also achieves a reduction in the size and complexity of the required optical elements and allows implementation using wafer level optics processes.

The invention discloses a variable light spot lens structure and laser equipment. The variable light spot lens structure comprises a fixing module (10) and a plurality of replacement modules (20), the fixing module (10) comprises a fixing base (11), a light source (12) arranged in the fixing base (11), a fast axis compression mirror arranged on the light emitting side of the light source (12), and a compression unit (13) fixed to the fixing base (11) and located on the light emitting side of the fast axis compression mirror. The multiple replacement modules (20) are arranged on the light emitting side of the fixing module (10) in a replacement mode, and each replacement module (20) comprises an optical head (21) and a shaping unit. The optical head (21) of each replacement module (20) can be detachably connected with the fixing seat (11) of the fixing module (10); light beams emitted by the light source (12) are subjected to fast axis compression of the fast axis compression mirror and compression of the compression unit (13), then enter the replacement module (20), are shaped by a shaping unit of the replacement module (20) and then are emitted; and the sizes of light spots obtained by the light beams emitted by any two replacement modules (20) on the receiving surface are different. The variable light spot lens structure can output various small-size light spots of different specifications, and the application flexibility of the laser module is improved.

A laser device provided with: a laser module that emits a plurality of laser beams; a condenser lens that condenses the plurality of laser beams; and an optical fiber that propagates the plurality of laser beams. When viewed from the X-axis direction, among the plurality of laser beams arranged along the Z-axis direction, the position of a laser beam on one side in the Z-axis direction with respect to a second reference line and the position of a laser beam on the other side in the Z-axis direction with respect to the second reference line are asymmetric with respect to the second reference line. The focal length of a fast axis collimation lens is greater than the minimum spacing between the plurality of laser beams.

The application relates to a kind of laser beam shaping systems and methods based on optical waveguide, belong to beam shaping technology.It includes semiconductor laser from left to right sequentially arranged, fast axis collimating lens, slow axis collimating lens, beam expander system, focusing lens and optical waveguide;Fast axis collimating lens is plano-convex cylindrical lens, for collimating the fast axis direction of light beam;Slow axis collimating lens is plano-convex cylindrical lens, for collimating the slow axis direction of light beam;Beam expander system includes preceding plano-concave cylindrical lens and following plano-convex cylindrical lens, for expanding the light beam width of slow axis direction to be consistent with the light beam width of fast axis direction;Focusing lens is plano-convex lens, for focusing light beam to optical waveguide input end;The input end section of optical waveguide is rectangle, and the output end section is circular, for shaping rectangular light spot into circular light spot.In the application, light beam is transmitted in optical waveguide efficiently, and gradually shaped into circular light beam through transition structure.

The present invention discloses a high-power Faraday laser based on spatial beam combining and its implementation method, comprising a high-power semiconductor laser diode array for generating multiple laser beams; a fast-axis collimating lens array for collimating the fast axis of each laser beam; a slow-axis collimating lens array for collimating the slow axis of each laser beam; a reflector array for spatially combining the multiple laser beams after both the fast and slow axes have been collimated, and then incident on a beam expanding lens assembly; a beam expanding lens assembly for expanding the incident light beam, and then incident on a Faraday atomic filter through a half-wave plate; a Faraday atomic filter for performing frequency-selective polarization rotation on the incident light, and then reflecting it through a second polarization beam splitter prism to a total reflection mirror, and then returning it to the high-power semiconductor laser diode array through the total reflection mirror to achieve external cavity feedback; and light with a frequency outside the transmission peak is transmitted through the second polarization beam splitter prism as the second output of the laser. The present invention significantly improves the light-to-light conversion efficiency.

This application discloses an optical detection device, comprising: a light source, a linear polarizer, a quarter-wave plate, an optical metasurface, and a light detection unit. The linear polarizer, quarter-wave plate, and metasurface are sequentially arranged along the propagation direction of the incident light. The metasurface comprises a transparent substrate layer and a dielectric nanocolumn layer. The fast axis of the quarter-wave plate has a first angle. When the first angle is a first characteristic angle, the light emitted from the quarter-wave plate is circularly polarized light. The light detection unit detects the optical power of the light emitted from the metasurface in a second angular direction, and obtains a second characteristic angle from the maximum optical power. The refraction angle is obtained from the wavelength of the incident light, the geometric parameters of the metasurface, and the refractive index of air. When the refraction angle is equal to the second characteristic angle, the first angle is the first characteristic angle. This device does not use a modulator or spectrometer, but only requires the pre-fabrication of the metasurface, which greatly reduces the device size and achieves miniaturization and integration.

The utility model relates to the technical field of lens sucking and clamping modules, in particular to a fast-axis lens sucking and clamping module, which improves the convenience of adjustment operation of a fast-axis lens by sucking and fixing the fast-axis lens in advance, prevents the fast-axis lens from falling off in the operation process by clamping and fixing after adjustment, and improves the use convenience. Comprising a clamp and a moving block which is installed on the outer side wall of the clamp in an up-down sliding mode. The fixture further comprises a positioning assembly, an air suction fixing assembly, a first clamping part, a second clamping part and a connector, the first clamping part is installed at the bottom end of the moving block, the positioning assembly is arranged at the bottom of the first clamping part and used for clamping and fixing the fast axis lens, the second clamping part is installed on the outer side wall of the fixture, an air flow channel is formed in the second clamping part, and the air suction fixing assembly is arranged on the air flow channel. An air suction fixing assembly is arranged at the bottom of the second clamping part, the air suction fixing assembly communicates with the airflow channel and is used for adsorbing and fixing the fast axis lens, and the connector is installed on the outer side wall of the clamp.

This invention discloses a laser and a laser projection device. The laser includes a metal thermally conductive substrate, multiple light-emitting chips, and multiple reflectors. The light-emitting chips are soldered to the substrate via heat sinks, and the reflectors are glued to the substrate. Each reflector faces the reflective surface of a corresponding light-emitting chip, allowing light emitted from that chip to be emitted in a direction away from the substrate. Each light-emitting chip emits light along a fast axis and a slow axis, wherein the fast axis is perpendicular to the substrate, the slow axis is parallel to the substrate, and the divergence angle of the emitted light along the fast axis is greater than that along the slow axis. Furthermore, the reflective surface is concave, and the beam emitted through the concave surface exhibits a greater contraction in the divergence angle along the fast axis than in the slow axis. The laser of this invention is used for efficiently emitting laser beams and is applied to laser projection devices.

The invention provides a laser ranging device and method. The device comprises a laser, a transmitting optical mechanism, a receiving optical mechanism and a signal processing / control module. A fast axis collimating mirror is integrated in the laser device and collimates a fast axis of laser emitted by the laser device. The emission optical mechanism comprises a cylindrical mirror and a collimation and beam expansion mechanism which are sequentially arranged along the laser propagation direction; the cylindrical mirror collimates the slow axis of the emergent laser, and the collimation and beam expanding mechanism reduces the divergence angle of the laser; the receiving optical mechanism comprises a receiving objective lens and an APD detector which are sequentially arranged in the laser reflection direction. The laser is reflected after irradiating a target, the receiving objective lens converges the reflected laser on a detection target surface of the APD detector, and the APD detector generates an electric signal according to the convergent light and outputs the electric signal to the signal processing / control module; and the signal processing / control module controls laser emission of the laser, and obtains the distance between the laser ranging device and the target according to the time interval between the laser emission moment and the electric signal receiving moment.

The application provides an alignment device and an alignment method. The alignment device is provided with a first polarization adjustment unit, which comprises a first wave plate and a second wave plate connected in sequence. Positive and negative orders of diffraction with the same diffraction order in diffracted light or scattered light pass through the first wave plate and the second wave plate respectively. The direction of the fast axis of the first wave plate and the direction of the fast axis of the second wave plate form a first included angle, so that the diffracted light or scattered light with any polarization state can form a first light beam with a first polarization direction and a second light beam with a second polarization direction after passing through the first polarization adjustment unit, and the alignment measurement is realized independently of the polarization state. Based on this, the application also provides an alignment device. The alignment device simultaneously processes the fifth light beam and the sixth light beam by using a second polarization adjustment unit, eliminates the phase difference of each detection signal, and reduces the risk of modulation depth reduction.

The invention relates to a device and method for measuring the beat length of a polarization maintaining optical fiber, and the device comprises a femtosecond optical fiber laser which is used for generating femtosecond pulses; the input end of the to-be-tested optical fiber is connected with the output tail fiber through the first optical fiber flange plate, and the output end of the to-be-tested optical fiber is connected with the input end of the optical fiber polarization beam splitter through the second optical fiber flange plate; and the output end of the optical fiber polarization beam splitter is directly connected to the input port of the spectrum analyzer. According to the method, a femtosecond fiber laser is adopted as a light source, a spectrum analyzer is adopted as detection equipment, and the beat length is measured by analyzing the wavelength corresponding relation of optical solitons on a slow axis and a fast axis of a polarization maintaining fiber. The method has the advantages that the device is simple, the operation is quick, and the repeatability is high. The method for measuring the beat length through cross-polarization Raman scattering is adopted, the light source and the polarization maintaining optical fiber to be measured are connected through the optical fiber flange plate, the consistency of the measurement result is good, the repeatability is high, and the manual operation error is small.