859 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 discloses an anti-turbulence free space optical communication method based on receiving and transmitting joint optimization, which balances the code length and the code rate through a Polar coding mode of an atmospheric turbulence channel, and ensures the coding and decoding overhead; meanwhile, a Transform model based on convolution enhancement is designed at a receiving end, learning of local features is enhanced through convolution, the relation between phase screen pixels is established, and a conjugate phase screen is given by the model for turbulence compensation. In order to solve the problem that in a free space optical transmission system, the atmospheric turbulence effect interferes with an OAM light beam, the influence of atmospheric turbulence interference on free space optical communication is relieved in a mode of joint optimization of the receiving end and the transmitting end. Error codes caused by atmospheric turbulence are corrected through Polar coding of the transmitting end, and the coupling efficiency of receiving light spots is improved after phase compensation of the receiving end, so that the mode purity obtained by corrected light spot images is improved, and the error rate of the system is reduced.

The invention discloses an optical chip-optical fiber coupler based on a collimating grating penetrating through a substrate, which belongs to the technical field of photoelectric chips and comprises a substrate, an inverted optical chip is arranged on the substrate, and the optical chip comprises at least one optical device, an optical waveguide array for realizing input and output and a collimating grating array. The collimating grating array is provided with a gradually changing period and duty ratio, so that light output from the optical waveguide array is diffracted to the substrate through the collimating grating array and is propagated to the back surface of the optical chip as basically collimated light; an optical coupling element array is arranged at the position, corresponding to emergent light of the collimating grating array, of the back face of the optical chip to couple light to an optical fiber array. By the adoption of the structure, high-efficiency coupling of the optical chip and the optical fiber array is achieved, and compared with a common grating coupler and an edge coupler, the coupler has higher coupling efficiency and alignment tolerance, is easier to manufacture and can be widely applied to the fields of optical IO, photoelectric sealing (CPO) and the like of large-scale photoelectric integrated chips.

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 an optical fiber temperature and pressure sensor based on a spherical lens and a preparation method thereof, and the sensor comprises a filler neck which is internally provided with a pressure medium channel; the sensitive diaphragm separates the pressure medium channel from the internal structure of the sensor, and can sense the pressure change of the pressure medium and convert the pressure change into self deformation; the optical fiber insertion core is used for fixing an optical fiber, so that the front end face of the optical fiber is close to and right faces the sensitive element sensitive diaphragm to form an optical FP cavity so as to realize pressure measurement; the spherical lens is used for converging light beams, improving the coupling efficiency of light entering the optical fiber end face and improving the optical signal intensity; the flat plate lens forms a reference FP cavity and is used for measuring temperature; the diaphragm base is used for mounting and fixing the sensitive diaphragm, the flat plate lens, the spherical lens and the optical fiber insertion core and ensuring that the sensitive diaphragm, the flat plate lens, the spherical lens and the optical fiber insertion core are coaxial and the relative positions are not changed; according to the scheme, the optical fiber has the characteristics of small size, high temperature resistance, high insulating property, high electromagnetic interference resistance and the like, and can be used for a long time in a high-temperature environment to measure the temperature and the pressure at the same time.

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 provides a debugging method for a fast optical fiber delay line, which comprises the following steps of: searching a driving shaft of a translation platform of a positioning motor as a main optical axis, converting the main optical axis by using a theodolite and a visible light laser, then adjusting two optical fiber collimating mirrors to enable the optical axes of the two optical fiber collimating mirrors to be parallel to the main optical axis, and adjusting the positions of two movable pyramid reflectors to realize debugging of the fast optical fiber delay line. It is ensured that the visible laser thin beam can sequentially pass through the reflectors and finally be emitted out of the other optical fiber collimating mirror. And finally, the optical fiber collimating mirror is finely adjusted to maximize the coupling efficiency average value of the optical fiber delay line and minimize the change rate of the optical fiber delay line, so that the coupling efficiency change of the optical fiber delay line is effectively controlled in the moving process of the translation stage, and the measurement precision of the terahertz time-domain spectrometer and the optical frequency comb 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 reconfigurable acoustical holography modulation method and device based on a crystalline polymer. The programmable acoustical holography device is composed of a single-layer photoresponse crystalline polymerization flat plate, is switched between two phases when the temperature irradiated by laser changes, has a crystalline state and a non-crystalline state, and reversibly changes along with the temperature. Space sound field modulation can be realized by spatially arranging the coding units, the crystalline polymer flat plate subjected to laser patterning phase change is recovered to the previous crystalline state after being cooled, the patterned coding acoustical holography disappears, and new phase acoustical holography is written in, so that a new sound field modulation function is realized. According to the programmable phase acoustical holography device based on the crystalline polymer, the incident plane wave of the probe can be modulated into any three-dimensional complex sound field, and the programmable phase acoustical holography device is of a complete plane type, is matched with underwater acoustic impedance, and is high in acoustic energy coupling efficiency, compact in structure, easy to prepare and low in price.

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 device suitable for double-end synchronous coupling mounting and a mounting method, and the device comprises a first pickup mechanism and a second pickup mechanism which are respectively used for picking up and adjusting different lens poses, and respectively putting the lens poses at an input end and an output end of a preset light path; the visual module is used for identifying the input end and the output end of the light path and guiding the first picking mechanism and the second picking mechanism to carry the lens to move; and the power detection module is used for receiving the output power of the different lenses coupled on the optical path. Through the device, the manual carrying and butt joint strength can be effectively reduced, meanwhile, the coupling precision can be improved, and the position and angle of the lens can be conveniently adjusted. And the output end and the lens at the output end can be coupled simultaneously, the coupling precision can be improved in multiple directions, the problem of coupling efficiency limitation caused by manual sequential butt joint is solved, the adjustment modes are diversified, and the product precision can be improved conveniently.

The invention discloses a device for coupling an optical fiber and an optical fiber collimator, and the device comprises a shockproof platform which is provided with two multi-axis mobile positioning platforms, one multi-axis mobile positioning platform is provided with an optical fiber fixing clamp, and the other multi-axis mobile positioning platform is provided with a collimator fixing clamp. The shockproof platform is further provided with a CDD image recognition control system used for achieving alignment coupling of the optical fiber located in the optical fiber fixing clamp and the optical fiber collimator located in the collimator fixing clamp. According to the invention, the coupling efficiency of the optical fiber and the optical fiber collimator is effectively improved, the alignment difficulty of the optical fiber and the optical fiber collimator is reduced, and the coupling stability of the optical fiber and the optical fiber collimator is enhanced.

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 relates to the technical field of optical communication, and provides an optical module coupling method, which comprises the following steps: S1, establishing a light spot distribution model according to each measured optical power value, S2, optimizing the alignment process of an optical element and a laser by combining the light spot distribution model, and finely adjusting the position of the optical element in an area with the highest light spot brightness, s3, dispensing and fixing the optical element, and S4, completing coupling. According to the optical module coupling method, the light spot distribution model is established and combined with the light spot distribution model to complete alignment, fine adjustment, alignment and other processes, so that the optimal coupling position is determined, the coupling efficiency and the signal integrity are improved, and the transmission loss is reduced.

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 provides an optical fiber nutation coupling system and method based on double-optical-wedge scanning, and relates to the technical field of free space optical communication, and the system comprises a double-optical-wedge scanning system, a nutation coupling mirror and an optical fiber which are sequentially arranged along an optical path. The double-optical-wedge scanning system is provided with two optical wedges, the vertical faces are parallel and opposite, the wedge faces are opposite, and nutation scanning is carried out through reverse and / or same-direction rotation of the two optical wedges. The nutation coupling mirror is used for focusing the target light beam into a light spot to be emitted to the optical fiber; the optical power meter, the nutation controller, the double-optical-wedge scanning system driver and the double-optical-wedge scanning system are electrically connected in sequence; the optical power meter is connected with the optical fiber transmitting end and used for measuring the optical power of the target beam coupled into the optical fiber; and the nutation controller is used for resolving the rotation angles of the two optical wedges, controlling the driver of the double-optical-wedge scanning system to apply voltage, and performing linkage control on the two optical wedges. According to the invention, the rotation of the two optical wedges is dynamically optimized, so that high and stable light output coupling efficiency is ensured, and power consumption is reduced.

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 invention discloses a grating coupling device and a preparation method thereof. The grating coupling device comprises a dielectric layer arranged on the surface of a substrate; the functional layer is arranged in the dielectric layer and is provided with a first grating and a waveguide which are adjacent to each other; the second grating is arranged in the dielectric layer and located on the side, away from the surface of the substrate, of the first grating, the grating constant of the second grating corresponds to the grating constant of the first grating, and the second grating is aligned to the first grating; and the material refractive index of the second grating is greater than that of the first grating. The overall coupling efficiency of the device can be obviously improved, and the coupling loss is reduced.

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 a slip ring wireless transmission structure applied to X-ray tomography equipment, which comprises a transmitting antenna and a receiving antenna, the transmitting antenna is composed of a transmitting transmission line and a transmitting adapter plate, the transmitting antenna is arranged on the radial outer side surface of a slip ring, and the receiving antenna is fixed on an equipment rack. The structures of the matching end of the transmitting antenna, the transmitting conversion plate and the receiving antenna are optimally designed, and the microstrip line with a periodic structure is used in the transmitting transmission line, so that compared with the wireless transmission structure of the existing equipment, the near-field coupling efficiency is improved, the return loss of the system is effectively improved, the signal-to-noise ratio is reduced, and the transmission efficiency is improved. Therefore, the transmission stability and reliability are effectively improved, and the use requirements of CT equipment can be better met.

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 provides a light-emitting substrate, a lighting device and a display device, and relates to the technical field of display. The anode layer is arranged on one side of the substrate; the electroluminescent layer is arranged on one side, far away from the substrate, of the anode layer; the cathode layer is arranged on one side, far away from the substrate, of the electroluminescent layer; the first covering layer is arranged on one side, far away from the substrate, of the cathode layer; the second covering layer is arranged on one side, far away from the substrate, of the first covering layer; the refractive index of the second covering layer is greater than that of the first covering layer; the packaging structure layer comprises a first inorganic packaging layer and is arranged on one side, far away from the substrate, of the second covering layer; the first covering layer can improve the coupling efficiency between the light-emitting microcavity and the packaging structure layer, and the light-emitting efficiency of the light-emitting substrate is effectively improved.

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.