692 results about "Coupling efficiency" patented technology

The invention relates to an optical fiber implantation monitoring method and device for composite material pressure-bearing equipment, and belongs to the technical field of composite material structure monitoring and intelligent sensing. According to the method, a distributed or point type optical fiber sensor and a composite material are synchronously integrated by designing a winding process, so that state parameters such as strain, temperature, pressure and the like of a key area of equipment are monitored in real time. The stability and the precision of the optical fiber in the laying process are ensured by adopting tool structures such as an embedded guide rail and an intelligent pay-off device; the tolerance and the coupling efficiency of the optical fiber are improved by combining the multi-layer structure design of the optical fiber flexible coating glue, the elastic coupling layer and the like; fBG, Brillouin and Raman sensing are fused through a temperature-stress cooperative monitoring system, and high-precision multi-physical field sensing is achieved. The system has the advantages of high integration level, low transformation cost and excellent monitoring performance, and is suitable for on-line health monitoring and intelligent early warning of composite material pressure-bearing equipment such as low-temperature high-pressure hydrogen storage cylinders, carbon fiber V-shaped cylinders and composite material pressure pipelines.

The invention relates to an anti-offset wireless charging coupler for an underwater vehicle, which solves the problem that the multi-dimensional offset charging efficiency is reduced due to ocean current by adopting the collaborative design of a grouped serial-wound transmitting end and a geometric adaptive receiving end. The transmitting end is formed by connecting an outer ring winding and an inner ring winding in series, the outer ring provides wide-area magnetic field coverage, the inner ring strengthens the local magnetic field intensity, and the ferrite array is combined to suppress magnetic leakage to cope with horizontal and rotary offset; the receiving end adopts a curved surface type structure and fits the geometric contour of an aircraft shell, interference of a rotation offset delta phi on a magnetic field is limited through optimal design of a coverage angle theta, and magnetic flux is concentrated by a ferrite array on the back side to improve the coupling efficiency. The system does not need complex mechanical adjustment, realizes energy transmission through magnetic field coupling, keeps stable efficiency in seawater, fresh water and air environments, has the advantages of compact structure, high offset resistance, wide medium adaptability and high expandability, and remarkably improves the reliability and cruising ability of wireless charging of the underwater vehicle.

The invention discloses a method for improving fusion plasma ion cyclotron heating efficiency, and belongs to the technical field of magnetic confinement fusion. The method comprises coupling use of an ion cyclotron antenna and a helical wave antenna, the ion cyclotron antenna is installed in a Tokamak vacuum chamber, is connected with an external radio frequency power supply through a coaxial line, and is used for exciting an ion cyclotron frequency band electromagnetic wave to heat plasma; and the helical wave antenna is arranged at a Tokamak window adjacent to the ion cyclotron antenna, is connected with a radio frequency power supply through a coaxial line or a rectangular waveguide, and is used for exciting a helical wave to increase the plasma density of a scraping layer and improve the accessibility of the ion cyclotron wave. The plasma is excited through the spiral wave antenna, so that the density of the scraping layer is improved, the coupling efficiency of the ion cyclotron wave and the plasma is improved, and technical support is provided for application of ion cyclotron heating in future high-parameter Tokamak.

The invention relates to the technical field of optoelectronics, and discloses a compact mixed optical path high-density integration method of a multi-level waveguide composite structure, which comprises the following steps: S1, preparing a multi-material layer: sequentially depositing a silicon layer, a silicon nitride layer and a lithium niobate layer, preparing the silicon layer and the silicon nitride layer through a chemical vapor deposition process, preparing the lithium niobate layer through direct current magnetron sputtering, and preparing the multi-material layer; the refractive indexes of the silicon layer, the silicon nitride layer and the lithium niobate layer meet gradient distribution; s2, designing an interlayer coupling structure: forming a gradient waveguide coupler at an interface of adjacent material layers to realize interlayer light field transmission; and S3, stress regulation and control layer integration: arranging a buffer layer with a matched thermal expansion coefficient between the silicon layer and the silicon nitride layer. According to the invention, the silicon layer, the silicon nitride layer and the lithium niobate layer are sequentially deposited, and the refractive index of each layer satisfies gradient distribution, so that the problems of large light field reflection and scattering loss and low coupling efficiency caused by the fact that most of the traditional multilayer waveguide structures adopt single material layers are solved.

The invention relates to the technical field of optical module coupling, and discloses optical module product double-Lens coupling equipment and a coupling method thereof.The coupling equipment comprises a jig module, a stock bin streamline module, a carrying module and two coupling modules arranged on the left side and the right side of the jig module, and the two coupling modules can be coupled with two Lens on an optical module product at the same time; an optical module clamping jaw of the carrying module can rotate around a Z axis, so that the direction of an optical module product reversely placed in a Tray can be corrected, and the coupling efficiency and quality of the optical module product are improved; in the coupling method, the stock bin streamline module can automatically provide and collect the Tray carrying the optical module product, and the carrying module can carry the optical module product between the stock bin streamline module and the jig module in a reciprocating manner, so that the coupling module can realize the coupling of the Lens and the optical module product, that is, the coupling method can coordinate the cooperation among the modules of the coupling equipment, and the coupling efficiency is improved. Therefore, the coupling logic is rigorous and orderly, and stable operation of the equipment is ensured.

The invention discloses a multi-channel runway micro-ring modulator capable of adjusting coupling efficiency, and the modulator comprises a runway micro-ring resonant cavity which comprises a straight waveguide section and a bent section and is used for achieving the resonance of an optical signal; the Mach-Zehnder modulation structure is integrated with the micro-ring resonant cavity and is used for adjusting the equivalent coupling coefficient of the micro-ring and the main waveguide; wherein the Mach-Zehnder modulation structure comprises a coupler, a mode converter and a modulation arm. And the modulator is also provided with a heater. According to the scheme, the coupling coefficient of the micro-ring resonant cavity and the main waveguide is adjusted through the Mach-Zehnder modulation structure, the limitation of the photon lifetime of the micro-ring resonant cavity on the modulation rate is overcome, and the restrictive relationship between the bandwidth and the modulation efficiency is broken. Compared with an existing micro-ring modulator, the micro-ring modulator can still have the high-speed modulation capacity in a high-quality-factor micro-ring resonant cavity. Meanwhile, through the design of the waveguide in the Mach-Zehnder interference region, the length of the modulation region is increased while the area of the device is not increased.

Various embodiments of the present disclosure are directed towards an integrated circuit. The integrated circuit includes a substrate having an upper face and a lower face. The upper face includes a central region and an outer sidewall that laterally surrounds the central region and that extends from the upper face to the lower face. An optical edge coupler is disposed over the upper face of the substrate and extends in a first direction from the central region toward the outer sidewall. An outer sidewall of the optical edge coupler corresponds to the outer sidewall of the substrate and has a concave surface or a convex surface.

The invention discloses a laser-assisted helium arc penetration fusion welding method, and belongs to the technical field of welding. The problems that according to an existing paraxial laser-electric arc composite structure, the welding track is difficult to control, the energy coupling efficiency is low due to laser energy loss, and weld joint partial melting and undercut defects are caused due to uneven distribution of a welding temperature field due to a generated asymmetric heat source are solved. The welding method comprises the steps of 1, pretreatment; 2, after being focused by a focus lens, the laser is divided into three laser beams through a spectroscope, then the three laser beams are converged again through a plurality of reflectors, three fan-shaped light spots are formed on the surface of the to-be-welded plate after convergence, and finally the focal plane position of the laser is adjusted to be located on the surface of the to-be-welded plate; 3, setting welding current and arc voltage; and fourthly, laser is used for assisting helium arc penetration fusion welding. The method is used for laser-assisted helium arc penetration fusion welding.

The invention discloses a moisture content measuring system and method based on a flexible conformal antenna sensor. Amplitude attenuation and phase deviation can occur when a microwave signal is propagated in a fluid to be measured, amplitude attenuation and phase deviation values are related to the dielectric constant of the fluid to be measured, and the dielectric constant of water at normal temperature is about 78 and is greatly different from the dielectric constant of oil or air. According to the invention, the moisture content information can be obtained by detecting the amplitude attenuation and the phase deviation value under the fixed frequency point. According to the invention, 0-100% full-scale moisture content measurement can be realized. The flexible conformal antenna sensor breaks through the fixed mode that the convex surface of a traditional conformal antenna radiates outwards, the design that the circular patch is embedded in the concave surface is adopted, the direction of a main wave beam is centripetally focused in the radial direction of a pipeline, directional radiation of electromagnetic waves to a to-be-detected fluid pipeline area is achieved, and the energy coupling efficiency between the electromagnetic waves and fluid is improved; and the dielectric property change of the whole watershed of the fluid is detected.

The invention provides double-lens coupling equipment and a double-lens coupling method, and belongs to the technical field of laser device production, the double-lens coupling equipment comprises a device tool, a lens tool, two coupling mechanisms and a detection mechanism, the lens tool is provided with two lens material waiting areas at the same time, the two lens material waiting areas can be used for placing a fast-axis collimating lens and a slow-axis collimating lens respectively, and the two lens material waiting areas can be used for placing the fast-axis collimating lens and the slow-axis collimating lens respectively; the two coupling mechanisms are arranged at the same time, coupling of one lens can be conducted through each coupling mechanism, during operation, the two coupling mechanisms conduct coupling of the fast axis collimating mirror and the slow axis collimating mirror respectively, light beam detection is conducted through the detection mechanism, and the coupling precision is ensured. Therefore, the double-lens coupling device can execute coupling of the two lenses at the same time, and the coupling efficiency is improved.

The invention discloses a channel-associated local oscillator free space continuous variable quantum key distribution method, which comprises the following steps of: initializing a receiving end telescope and a transmitting end telescope, detecting the local oscillator light intensity of a receiving end, adjusting the telescopes to be in an optimal coupling efficiency state, and tracking the change of beacon light through a fine tracking and pointing system of the telescopes so as to maintain the stability of a communication link; a transmitting end performs heterodyne detection on 90% of thermal-state optical signals after polarization and beam splitting of a thermal-state light source, results X and P serve as local initial secret keys, the other 10% of thermal-state optical signals are attenuated and then combined with local oscillation light to be transmitted to a receiving end through a free space channel so as to perform homodyne or heterodyne detection, and corresponding initial continuous secret key data are obtained; and the receiving end performs data frame synchronization, phase compensation, parameter evaluation, error correction and confidentiality enhancement on the obtained initial continuous key data to obtain a binary bit key. The channel associated local oscillator free space CVQKD safe coding based on the thermal state source is realized, and the average key distribution rate under a-15dB attenuation channel reaches a thousand bps magnitude.

The invention discloses a double-core optical fiber integrated MZ interferometer based on thermal diffusion. The interferometer is mainly characterized in that a core structure of the interferometer is formed by sequentially welding an input optical fiber (1), a first double-cladding transition optical fiber (2), a double-core optical fiber (3), a second double-cladding transition optical fiber (4) and an output optical fiber (5). Thermal diffusion treatment is performed by long-term high-temperature heating in the welding regions (A) and (B). The thermal diffusion treatment enables fiber core doping elements to be diffused, a transition area is formed in the double-clad optical fiber, the coupling efficiency between the single-mode optical fiber and the double-core optical fiber is remarkably improved, and compared with a traditional tapering structure, the thermal diffusion area is higher in mechanical strength. The interferometer device is compact in structure, high in integration level and excellent in interference contrast, can realize high-precision phase sensitive sensing, is suitable for distributed measurement of physical quantities such as temperature, bending and refractive index, and can be widely applied to optical fiber sensing.

The invention discloses a video behavior recognition method based on multi-scale time feature fusion, and the method comprises the steps: taking a dual-path network as a basic structure, carrying out the normalization and uniform frame extraction of an input video, and respectively inputting a Slow path and a Fast path for feature extraction. The Slow path focuses on low-frequency background semantic modeling, the Fast path integrates a dynamic Token sparse module (VDTS) constructed based on one-dimensional convolution, and a key action area is adaptively selected through a Gumbel Top-K mechanism. Furthermore, according to the method, a gating bidirectional cross attention module (Bi-CAM) is designed between a fast path and a slow path, dynamic complementary fusion of bidirectional information streams is achieved by introducing a Query-Key-Value fusion structure and a channel attention gating mechanism, and the coupling efficiency and expression ability between multi-scale features are effectively improved. And finally, accurate recognition of behavior categories is completed through a classifier. The method gives consideration to the recognition precision and the calculation efficiency, is suitable for scenes such as behavior monitoring, man-machine interaction and intelligent security and protection, and has a good application prospect.

The invention discloses a preparation and coupling optimization method of a strip-shaped SOI waveguide adopting end face coupling, and belongs to the field of micro-nano fine structure processing and optical precision measurement. According to the method, through two-step photoetching and two-step etching, on one hand, the substrate section highly coincident with the waveguide end face can be etched on the waveguide end face, and on the other hand, it can be guaranteed that the etching broadening of the Si substrate etching channel cannot cause the hollow-out of the lower portion of the waveguide above SiO2. By using the direct-current magnetron sputtering Cr mask, the waveguide material can be prevented from being etched and damaged in the deep silicon etching process. Through the ion beam etching process, the end face of the waveguide and the etched side wall of the substrate are completely overlapped, so that part of light spots are prevented from being scattered by the Si substrate in the optical fiber coupling process, and the coupling efficiency of the waveguide is further improved. By combining the FDTD simulation result, the low-internal stress SiO2-Si3N4 antireflection film with the proper thickness is deposited on the waveguide end face through ICP-PECVD, light spots are prevented from being reflected on the waveguide end face, and the light spot coupling efficiency reaches the maximum.

The invention relates to the technical field of spectrum detection, and particularly discloses a preparation method of a microstructure enhanced optical fiber and a Raman spectrometer light collection system thereof, the system comprises: a light source assembly for generating laser and performing collimation treatment on the laser to make the collimated laser irradiate a to-be-detected sample; the detection area assembly is used for placing a to-be-detected sample and positioning the to-be-detected sample; the collection assembly is used for collecting Raman scattering light generated by the sample to be detected under laser irradiation based on the microstructure enhanced optical fiber, and the optical fiber end face of the microstructure enhanced optical fiber is provided with a micro-nano structure; the geometric parameters of the micro-nano structure are determined by global optimization by using the genetic algorithm to maximize the coupling efficiency of the unpolarized diffused light in a preset wavelength range as an optimization target; and the control analysis assembly is used for carrying out signal acquisition from the collected Raman scattering light and identifying component information corresponding to the to-be-detected sample through a preset component identification model based on a signal acquisition result.

The utility model provides a narrow-band single-fiber four-way wave combining optical device, which comprises a cube, and an optical port end, a laser end and a detector end which are arranged on three side surfaces of the cube, and the interior of the cube further comprises a low-optical-level wave dividing assembly, a double-channel free space optical isolator and C-l ens. The laser end emits two parallel wave band lights, the two parallel wave band lights are combined into one path after being isolated by the double-channel free space optical isolator and being refracted and reflected by the low-optical-level optical branching assembly for multiple times, and the C-lens converts the parallel lights into convergent lights and then couples and converges the convergent lights to the optical port end. Receiving wave band light input from the light port end is converted into parallel light through C-l ens, the parallel light enters the low-optical-level wave division assembly and is divided into two paths to enter the detector end after being refracted and reflected for multiple times, and the two paths of parallel receiving wave band light are converged to the two detector photosensitive surfaces through the detector end respectively. According to the narrow-band single-fiber four-way wave combining optical device, wave combining and wave dividing optical paths are optimized through the low-optical-level optical wave dividing assembly, the coupling efficiency and the isolation degree of the device are improved, crosstalk is reduced, meanwhile, all ports and structures are highly integrated, and the miniaturization design of the optical device is achieved.

The invention relates to an optical waveguide coupler based on a hard substrate and a preparation method thereof, and belongs to the technical field of couplers. The method comprises the following steps: preparing a lower rectangular waveguide core layer on a hard substrate through an ultraviolet lithography technology; preparing a lower reflecting micro-mirror through an excimer laser technology, and plating a reflecting film on the surface of the lower reflecting micro-mirror; then preparing an upper rectangular waveguide core layer through an ultraviolet lithography technology on the basis; preparing an upper reflecting micro-mirror at a corresponding vertical position of the lower reflecting micro-mirror through an excimer laser technology, and plating a reflecting film on the surface of the upper reflecting micro-mirror; the optical waveguide coupler prepared by the method realizes high-density interlayer interconnection, and is relatively high in application flexibility and high in interlayer coupling efficiency.

The invention relates to the technical field of spot-size converters, and discloses a lithium niobate film spot-size converter with an asymmetric trident structure and a preparation method of the lithium niobate film spot-size converter with the asymmetric trident structure. The lithium niobate film waveguide layer is positioned on the insulating layer; the silicon dioxide layer is coated on the lithium niobate film waveguide layer; the silicon nitride waveguide layer is located on the silicon dioxide layer; the silicon nitride waveguide layer comprises a first waveguide part, a second waveguide part and a third waveguide part which are connected in sequence in the direction from the input end to the output end of the lithium niobate film spot size converter, and the first waveguide part, the second waveguide part and the third waveguide part are located on the same plane; in the light wave transmission direction, the transverse size of the second waveguide part is sequentially increased, and the transverse size of the third waveguide part is sequentially reduced; according to the invention, the process preparation difficulty is low, high-efficiency coupling with the coupling efficiency of more than 90% from the silicon nitride waveguide to the lithium niobate waveguide can be realized, and the optical fiber coupling alignment tolerance and overlay tolerance as well as the overall coupling efficiency of the spot size converter are improved.

The application provides a MEMS resonator and a MEMS resonator array. The MEMS resonator comprises a vibration unit, a coupling energy storage unit, an anchor point and a first electrode. The vibration unit is used for generating resonance. The coupling energy storage unit is coupled with the vibration unit and is a high-Q vibration mode. The anchor point fixes the coupling energy storage unit on a substrate. The first electrode is arranged adjacent to the vibration unit and has a gap between the vibration unit. The application sets the coupling energy storage unit in the MEMS resonator. On the one hand, the coupling energy storage unit is equivalent to introducing other high-Q bulk mode vibration structures on the basis of the existing vibration unit, so as to improve the resonance Q value of the whole MEMS resonator. On the other hand, the coupling energy storage unit is coupled with the vibration unit, the coupling area is increased, the coupling efficiency is improved, and the resonance Q value is further improved. In addition, the coupling area of the coupling energy storage unit and the vibration unit can be increased, which is also beneficial to improve the coupling efficiency.

The invention discloses a surface emitting laser which solves the problems that a laser is poor in single-mode working stability and high in preparation process difficulty. The surface emitting laser comprises a substrate and an epitaxial structure which are arranged in a stacked mode, the epitaxial structure is provided with a plurality of holes, the section of each hole is roughly in a T shape, the sections are parallel to the substrate, filler is arranged in the holes, and the refractive index of the filler is different from that of the epitaxial structure. Under the same mode field area and surface emission coupling efficiency, the threshold gain difference between the base mode and the high-order resonance mode of the laser is large, and the stability of the single-mode working state is high. And the hole machining difficulty of the T-shaped structure is low.

The invention provides a heterocyclic derivative and an organic electroluminescent device thereof, and belongs to the technical field of organic electroluminescence. The heterocyclic derivative provided by the invention has relatively weak metal adsorption capacity, when the heterocyclic derivative is used as a nucleation inhibition layer material to be applied to the organic electroluminescent device, deposition of metal on the surface of a thin layer can be effectively inhibited, and meanwhile, the heterocyclic derivative is used as a covering layer material to improve the optical coupling efficiency of the organic electroluminescent device, so that the organic electroluminescent device can be applied to the field of organic electroluminescent devices. And the luminous efficiency of the device is effectively improved. The heterocyclic derivative and the organic electroluminescent device thereof have good application effect and industrialization prospect.

The invention relates to a DR4 silicon optical chip, which is characterized in that one side surface of a chip main body is an optical surface inclined by 8 + / -0.1 degrees, four output waveguides which are perpendicular to and intersect with the optical surface are arranged on the chip main body side by side, and an input waveguide which intersects with the optical surface is arranged on the chip main body. According to the 400G silicon optical engine, the end face of a multi-channel optical fiber array is a 0-degree face, the 0-degree face of the multi-channel optical fiber array is attached to the optical face of a DR4 silicon optical chip, and the multi-channel optical fiber array is coupled with four output waveguides on the DR4 silicon optical chip. The beneficial effects are that the DR4 silicon optical chip is provided with an optical surface with an inclination of 8 + / -0.1 degree, and the output waveguide is perpendicular to and intersects with the optical surface, so when the DR4 silicon optical chip is applied to a 400G silicon optical engine, the end surface of the selected multichannel optical fiber array can be a 0-degree surface, the grinding efficiency of the multichannel optical fiber array is effectively improved, the angle error is reduced, and the grinding precision is improved. The coupling efficiency is improved.

The invention provides a topological posture single photon source device and a quantum light source, and relates to the technical field of topological quantum light sources. The topological state single photon source device comprises a GaAs layer; the SiO2 / Au structure comprises a SiO2 layer and an Au layer, and is positioned below the GaAs layer to serve as a reflecting mirror for inhibiting backward photon leakage; the topological state microcavity is processed and formed on the GaAs layer; and the quantum dots grow in the GaAs layer and are coupled with the topological posture of the topological posture microcavity to generate a topological posture single photon source. According to the invention, the coupling efficiency of the quantum dots and the microcavity is effectively improved by using the mode volume with a relatively large topological posture, the bottleneck that the coupling probability is low due to the limited volume of a traditional mode is broken through, and a better scheme is provided for realizing the interaction of high-efficiency light and substances.

The invention discloses a high-precision end face coupling device and a coupling method, and relates to the technical field of optical chip packaging, the end face coupling device comprises a displacement table, a support, a coupling module, a coupling module and a power supply module, the output end of a semiconductor laser chip extends to the outside of one end of the surface of the displacement table, and the input end of the support extends to the outside of one end of the surface of the support. The output end extends out of the other end of the surface of the bracket; a light source that irradiates a gap between the semiconductor laser chip and the optical chip; the camera is used for receiving an optical gap image formed by the gap and coupling the semiconductor laser chip and the optical chip based on the real-time distance; and the power meter is used for measuring the optical power output by the optical chip in the coupling process and judging whether the coupling efficiency between the semiconductor laser chip and the optical chip reaches the highest or not according to the optical power. Whether the semiconductor laser chip is touched or not in the coupling process can be accurately judged, and the end face of the laser cannot be touched during submicron distance coupling.

The invention provides a heterogeneous integrated sub-wavelength structure end face coupler adaptive to a single-mode optical fiber and a preparation method of the heterogeneous integrated sub-wavelength structure end face coupler, and relates to the technical field of integrated optics. The coupler comprises a substrate, an insulating layer, a waveguide layer and a cladding from bottom to top. The waveguide layer comprises an upper lithium niobate ridge waveguide and a lower lithium niobate ridge waveguide, the lower waveguide is wider than the upper waveguide, and the upper waveguide is used for connecting an external waveguide; the heterogeneous integrated coupling region comprises a silicon nitride strip conical waveguide which forms directional coupling with the lower-layer lithium niobate waveguide, so that adiabatic transfer of a light field is realized; the sub-wavelength grating regulation and control region sequentially comprises a silicon nitride tapered waveguide and sub-wavelength grating combination section, a width gradually-changing grating section and an equal-width buffer grating section. The whole structure is symmetrical about the central axis. Through the multi-section adiabatic transformation and heterogeneous integration design, efficient expansion of a mode field is achieved, the coupling efficiency with a single-mode fiber is improved, and the advantages of being insensitive to polarization, good in process compatibility and suitable for high-density integration are achieved.

The invention provides a coupling system for an on-chip light source and a photon chip. The coupling system comprises an input light source, a collimating lens, a focusing lens, a reflecting prism and an on-chip grating which are sequentially arranged in the direction of a light path, and an optical waveguide located on the side face of the on-chip grating. The collimating lens is used for primarily shaping emergent light of an input light source into a collimated light beam, the focusing lens is used for focusing the collimated light beam to the on-chip grating, and the collimating lens and the focusing lens are both aspheric plano-convex lenses. According to the system, non-uniformity caused by a large divergence angle of the semiconductor laser is effectively corrected through the aspheric micro lens, output of approximately parallel light beams is achieved, the light beams are accurately focused to the photon chip grating through the aspheric focusing lens subsequently, the coupling efficiency of light energy is greatly improved, and compared with two cylindrical lenses in the prior art, the coupling efficiency of light energy is greatly improved. The design of the focusing lens and the reflector is added, so that the number of optical elements is reduced, and error accumulation is reduced.

The invention provides a spatial optical coupling efficiency rapid assembling and correcting method based on multimode optical fiber receiving, and solves the problems that the spatial translation and angle of an optical fiber end face need to be repeatedly and manually adjusted in an existing assembling and correcting method, single-time adjustment needs to consume more than 2 hours and needs to depend on experience of an operator; moreover, the precision deviation of manual reset can reach + / -5 [mu] m, resulting in that the coupling efficiency fluctuation exceeds + / -10%, and the consistency requirement in batch production is difficult to meet, and can be widely applied to the field of laser communication. The method specifically comprises the following steps: connecting a multimode fiber with a laser, and receiving a light beam refracted by a coupling receiving lens group by using a light beam analyzer; adjusting the position of a transmitting platform of the multimode optical fiber for multiple times, and recording the size and roundness of the light spot after each adjustment through an upper computer; in the recorded size and roundness data of the light spot, determining the relative minimum value of the size of the light spot when the roundness of the light spot is greater than 0.87; and the position of the emission platform with the relative minimum light spot size is used as the optimal installation and calibration position.

The invention discloses a polarization sensitive type broadband absorber based on metal-medium stacking, and relates to the technical field of micro-nano photonic devices and infrared detection. The absorber sequentially comprises a bottom-layer high-loss metal reflecting layer, a multi-layer stacked composite dielectric cavity structure and a top-layer sub-wavelength metal grating from bottom to top, according to impedance matching and interference resonance theories, a broadband absorption substrate is constructed through a multi-layer film structure at the bottom, and light energy is converted into heat energy by utilizing the high loss characteristic of bottom layer metal; plasmon resonance is excited through the top metal grating, the coupling efficiency of TM polarized light is enhanced, and TE polarized light is cut off; the above structural design successfully realizes efficient broadband absorption and high polarization extinction ratio in an infrared band. The structure is simple in design, is compatible with a CMOS technology, and has excellent wide-angle stability. And meanwhile, polarization screening can be realized without an external polaroid, and miniaturization and integration of an infrared detection system are facilitated.

The utility model discloses an optical assembly and an optical module, which comprise an optical fiber connector component and a wavelength division multiplexing component, a first optical component is arranged between the optical fiber connector component and the wavelength division multiplexing component, and the first optical component is used for focusing and inputting light beams output by an optical fiber head to the input end of the wavelength division multiplexing component. The output end of the wavelength division multiplexing component is provided with a second optical component used for turning the light beams output by the wavelength division multiplexing component to the receiving end. The coupler has the advantages of being simple in structure, convenient to assemble, high in coupling efficiency, small in loss and high in channel quality.

Systems and methods to improve efficiency of in-coupling electromagnetic waves, such as in a visible light wavelength range, into a waveguide system arrangement are disclosed. The waveguide system includes: a display or an illumination assembly; a waveguide substrate; a polarization volume grating or a spin-dependent bifacial metasurface as in-coupler, which efficiently couples electromagnetic waves, such as in a visible light wavelength range, into the waveguide substrate. An out-coupler can couple the electromagnetic waves, such as in a visible light wavelength range, out of the waveguide substrate.