230 results about "Transverse mode" patented technology

Aspects of this disclosure relate to an acoustic wave device with transverse mode suppression. The acoustic wave device can include a piezoelectric layer, an interdigital transducer electrode, a temperature compensation layer, and a mass loading strip. The mass loading strip can overlap edge portions of fingers of the interdigital transducer electrode. The mass loading strip can have a sidewall that is tapered inwardly from a bottom side of the mass loading strip to a top side of the mass loading strip. The top side can be shorter than the bottom side.

The invention provides a TF-SAW resonator, a preparation method thereof and a filter, and relates to the technical field of semiconductors. The interdigital electrode comprises piston structures, sub-bus bars and metal bumps, the piston structures are positioned at two ends of the acoustic part, it can be understood that the piston structures are arranged at the tail end areas of the acoustic part on the electrode finger strips, and larger sound velocity difference is realized by changing the sound velocity of the tail end areas; therefore, the transverse mode is reflected in different directions to avoid energy dissipation caused by resonance; on a propagation path of a transverse mode, the sub bus bars and the metal bumps are sequentially arranged, clutter interference is eliminated by causing sound velocity difference, so that clutter mode interference is inhibited to the greatest extent, the Q value is improved, the insertion loss flatness in a passband is improved, and the performance of the TF-SAW resonator is further improved.

The present invention relates to multi-stake underwater transducers and arrays for the generation and reception of sound waves in water. The invention provides the design and fabrication of compact piston-type underwater transducers of low-to-mid operating frequency made of piezoelectric single crystals without the need of any pre-stress mechanism. The invention uses a multi-stake pipe-like motor section made of piezoelectric single crystals of high transverse mode piezoelectric coefficients and low acoustic impedance, and small-diameter and light head mass(es). The present invention also discloses various means of increasing the bandwidth of the multi-stake underwater transducers as well as derivative transducers and arrays made of them, including compact 2D and 3D omni-directional transducers, planar, conforming and shaped arrays of various designs, high-density arrays and low-drop-down-ratio parametric arrays of either single or dual frequency bands.

An acoustic wave device, a radio frequency filter and an electronics module are provided. The acoustic wave device, comprises a layer of piezoelectric material, a pair of interdigital transducer electrodes disposed on an upper surface of the layer of piezoelectric material, each interdigital transducer electrode including a bus bar and a plurality of electrode fingers extending from the bus bar through a central region of the interdigital transducer electrode towards an edge region of the interdigital transducer electrode, each of the plurality of electrode fingers having a width in a direction perpendicular to the extension of the electrode fingers that is smaller in the edge regions than in the central regions, and trench portions located in the upper surface of the layer of piezoelectric material, the trench portions overlapping with the edge regions of the interdigital transducer electrodes. The acoustic wave device provides effective suppression of transverse modes.

The invention provides a TF-SAW resonator, a preparation method thereof and a filter, and relates to the technical field of semiconductors. The interdigital electrode comprises piston structures, sub-bus bars, metal bumps and recesses, the piston structures are positioned at two ends of the acoustic part, it can be understood that the piston structures are arranged at the tail end areas of the acoustic part on the electrode finger bars, and larger sound velocity difference is realized by changing the sound velocity of the tail end areas; therefore, the transverse mode is reflected in different directions to avoid energy dissipation caused by resonance; according to the TF-SAW resonator, the sub bus bars, the metal bumps and the recesses are arranged on a propagation path of a transverse mode, clutter interference is eliminated by causing sound velocity difference, so that clutter mode interference is inhibited to the greatest extent, the Q value is improved, the insertion loss flatness in a passband is improved, the performance of standing waves in the passband is improved, the insertion loss is improved and the like, and the performance of the TF-SAW resonator is further improved.

The invention provides a well drilling anti-interference communication system based on a VCSEL (Vertical Cavity Surface Emitting Laser), the VCSEL and a manufacturing method thereof, and the manufacturing method comprises the following steps: calculating the light field intensity distribution of a high-order transverse mode through an intrinsic mode expansion method and a Laguerre-Gaussian model based on the epitaxial structure parameters of a laser; determining a target area which begins to perform downward annular etching on the surface of the p-DBR layer, wherein the target area coincides with a light field intensity peak area of the high-order transverse mode; performing annular etching in the target area to form an annular groove, and etching at least seven pairs of p-DBR layers inwards in the groove; the communication system comprises a signal transmitting end arranged on the derrick side, and the signal transmitting end is provided with the vertical cavity surface emitting laser; the p-DBR region of the vertical cavity surface emitting laser is provided with an annular etching structure; the graded-index fluorinated plastic optical fiber is used as a transmission medium and is connected with the derrick side and the logging room side; and the optical signal receiving end is arranged at the logging room side and is used for receiving and converting the optical signal into an electric signal.

The utility model discloses a surface acoustic wave device and a radio frequency front-end module. The surface acoustic wave device comprises an interdigital transducer, wherein the interdigital transducer comprises a first bus bar and a second bus bar which are oppositely arranged, an electrode finger and a plurality of gap electrodes; in the extending direction of the electrode fingers, an overlapping area is formed between the first bus bar and the second bus bar, a first area is formed between the overlapping area and the first bus bar, a second area is formed between the overlapping area and the second bus bar, and the first area and the second area are adjacent to the first bus bar and the second bus bar respectively; the plurality of gap electrodes are arranged in at least one of the first area and the second area, and the plurality of gap electrodes, the bus bars and the electrode fingers are arranged at intervals; wherein the plurality of gap electrodes form a first curve in the arrangement direction of the electrode fingers. According to the invention, the Q value near the anti-resonance point can be improved while the inhibition effect of the transverse mode is improved.

The invention discloses a surface acoustic wave resonator and a filter. The surface acoustic wave resonator comprises a piezoelectric layer; the electrode layer is arranged on the piezoelectric layer; the electrode layer comprises an interdigital transducer; the interdigital transducer comprises two interdigital electrodes which are oppositely arranged in a first direction; each interdigital electrode comprises a bus bar, a plurality of interdigital strips which are connected with the bus bar, extend in the first direction and are arranged in the second direction, and a plurality of sinking false fingers which are positioned on one side, far away from the bus bar, of each interdigital strip and extend in the first direction; the first direction intersects with the second direction; and each sinking false finger sinks into the piezoelectric layer. According to the technical scheme, clutters of a transverse mode can be effectively restrained, meanwhile, the process steps are simplified, and device miniaturization is facilitated.

The invention relates to the technical field of filters, and discloses a resonator and a surface acoustic wave filter, and the resonator comprises an interdigital transducer and a transverse strip structure. The interdigital transducer comprises a first bus bar, a second bus bar, a plurality of first finger bars and a plurality of second finger bars; the first bus bar and the second bus bar are oppositely arranged, the same ends of the plurality of first finger bars are connected with one side, close to the second bus bar, of the first bus bar, and the same ends of the plurality of second finger bars are connected with one side, close to the first bus bar, of the second bus bar; the transverse strip structure is arranged in a target area of the interdigital transducer; the transverse strip structure comprises a plurality of first transverse strips and a plurality of second transverse strips, the first transverse strips and the second transverse strips are arranged in a crossed mode, the adjacent first transverse strips and second transverse strips are distributed in a staggered mode, and the first ends, in the first direction, of the first transverse strips are connected with the third ends, in the first direction, of the second transverse strips. According to the resonator provided by the invention, the Q value of the resonator can be improved while a transverse mode is effectively suppressed.

The invention relates to a piezoelectric resonator, which belongs to the technical field of micro electro mechanical systems, and comprises a resonant body on which micropore structures are periodically arranged; the resonant body is fixed on the substrate, and a cavity or an acoustic reflecting layer is arranged between the substrate and the resonant body; wherein the micropore structure and part of the resonance body around the micropore structure form an in-plane coupling unit which is used for exciting the coupling mode of the resonator. Compared with the prior art, the in-plane coupling units arranged in the x-y plane of the resonator can excite transverse modes in the x-axis direction and the y-axis direction at the same time, an in-plane two-dimensional transverse coupling mode is formed, and the transverse coupling mode is the basis for achieving the photoetching tuning characteristic of the resonator. Appropriate sizes and in-plane arrangement of the in-plane coupling units are defined through a photoetching process, and the resonant frequency of the resonator can be adjusted in a wide frequency band range.

The invention provides a TF-SAW resonator, a preparation method thereof and a filter, and relates to the technical field of semiconductors. The interdigital electrode comprises piston structures, sub bus bars and recesses, the piston structures are positioned at two ends of the acoustic part, it can be understood that the piston structures are arranged at the tail end areas of the acoustic part on the electrode finger strips, and larger sound velocity difference is realized by changing the sound velocity of the tail end areas; therefore, the transverse mode is reflected in different directions to avoid energy dissipation caused by resonance; on a propagation path of a transverse mode, sub-bus bars and recesses are sequentially arranged, clutter interference is eliminated by causing sound velocity difference, so that clutter mode interference is inhibited to the greatest extent, a Q value is improved, the performance of standing waves in a passband is improved, insertion loss is improved and the like, and the performance of the TF-SAW resonator is further improved.

The invention discloses a surface acoustic wave resonator and an electronic device, which are applied to the technical field of surface acoustic waves, an interdigital transducer comprises two outer-layer bus bars arranged oppositely and at least two inner-layer bus bars arranged oppositely, the inner-layer bus bars are arranged between the outer-layer bus bars, and the outer-layer bus bars and the inner-layer bus bars are both parallel to the length direction; the inner-layer bus bar is provided with a plurality of first protruding parts protruding out of the edge of the inner-layer bus bar in the width direction, the first protruding parts are arranged in the length direction, so that an inner-layer edge sound velocity area is formed on at least one side of the inner-layer bus bar based on the first protruding parts, and an inner-layer sound velocity area is formed on the basis of the inner-layer bus bar; the sound velocity of the inner-layer edge sound velocity area is smaller than that of the inner-layer sound velocity area. The sawtooth structure formed by the plurality of first protruding parts can enable sound waves to generate diffuse reflection during transverse propagation, so that the Q value of a transverse clutter mode is reduced, and the generation of a transverse mode is effectively inhibited.

A multilayer piezoelectric substrate acoustic wave device including an active region having a center region and a border region is disclosed. The acoustic wave device can include a support substrate, a piezoelectric layer over the support substrate, and an interdigital transducer electrode in electrical communication with the piezoelectric layer. The piezoelectric layer has a trench in the border region. The interdigital transducer electrode includes a bus bar and a finger extending from the bus bar. The finger in the border region has a first portion with a first width, a second portion with a second width between the center region and the first portion, and a third portion with a third width between the center region and the second portion. The second width is narrower than the first width and the third width.

The invention relates to the technical field of lasers, in particular to a vertical-cavity surface-emitting laser and a preparation method thereof, and the vertical-cavity surface-emitting laser comprises a substrate layer, an N-type DBR structure, a first spacing layer, an active layer, a second spacing layer and a P-type DBR structure which are stacked in sequence; wherein the P-type DBR structure is formed by alternately arranging a high-refractive-index P-type semiconductor layer and a low-refractive-index P-type semiconductor layer for a plurality of cycles, and the low-refractive-index P-type semiconductor layer is a P-type semiconductor layer containing an Al component; a low-refractive-index P-type semiconductor layer adjacent to the second spacing layer in the P-type DBR structure is used as a first oxidation limiting layer, and the molar fraction of Al component in the first oxidation limiting layer before oxidation is greater than 0.98. According to the invention, the single transverse mode output characteristic of the vertical cavity surface emitting laser under high power can be improved at least.

Aspects of this disclosure relate to an acoustic wave device with transverse mode suppression. The acoustic wave device can include a piezoelectric layer, an interdigital transducer electrode, a temperature compensation layer, and a mass loading strip. The mass loading strip can overlap edge portions of fingers of the interdigital transducer electrode. The mass loading strip can have a sidewall that is tapered inwardly from a bottom side of the mass loading strip to a top side of the mass loading strip. The top side can be shorter than the bottom side.

To provide an optical fiber light source having high spectral wavelength flexibility and enabling incoherent continuous-wave output in a single transverse mode.SOLUTION: An optical fiber light source has: an optical fiber having a first end, a second end, and a tapered part positioned between the first and second ends, which is a single mode fiber; a wavelength conversion part; a light source for exciting the wavelength conversion part; and a support part. The first end outputs radiant light emitted from the excited wavelength conversion part. The tapered part includes: a constricted part; a first tapered region in which a diameter gradually decreases from the second end side toward the constricted part; and a second tapered region in which a diameter gradually increases from the constricted part toward the first end side. The constricted part has a diameter smaller than those of the first and second ends, and has a size of the wavelength or less of the radiant light. The wavelength conversion part is composed of liquid or gas and is disposed so as to surround at least an outer periphery of the constricted part of the tapered part. The light source simultaneously excites the outer peripheral portion surrounding the wavelength conversion part.SELECTED DRAWING: Figure 2

The invention provides a bulk acoustic wave resonator, a filter and electronic equipment. The bulk acoustic wave resonator comprises a substrate layer, a Bragg reflection layer arranged on the substrate layer and a piezoelectric transduction structure layer arranged on the Bragg reflection layer. The Bragg reflection layer comprises a plurality of film layers which are arranged in a stacked mode, and the refractive indexes of every two adjacent film layers are different; the piezoelectric transduction structure layer comprises a piezoelectric layer and an electrode layer which are stacked; at least one film layer, close to the piezoelectric transduction structure layer, in the Bragg reflection layer is a preset film layer, the preset film layer comprises cavity parts and supporting parts, the cavity parts and the supporting parts are alternately arranged in the first direction, and the first direction is parallel to the substrate layer. According to the bulk acoustic wave resonator, acoustic wave energy is concentrated on the piezoelectric layer through the cavity parts, the electromechanical coupling coefficient of the bulk acoustic wave resonator is increased, under the alternate arrangement of the cavity parts and the supporting parts, the slowness curve of the main vibration mode of the bulk acoustic wave resonator is flattened, the transverse mode and stray response are restrained, and therefore the quality factor of the bulk acoustic wave resonator is improved.

Aspects of this disclosure relate to an acoustic wave device with transverse mode suppression. The acoustic wave device can include a piezoelectric layer, an interdigital transducer electrode, a temperature compensation layer, and a multi-layer mass loading strip. The mass loading strip has a density that is higher than a density of the temperature compensation layer. The mass loading strip can overlap edge portions of fingers of the interdigital transducer electrode. The mass loading strip can include a first layer for adhesion and a second layer for mass loading. The mass loading strip can suppress a transverse mode.

The invention provides a resonator with a transverse mode suppression structure and a manufacturing method thereof.The resonator comprises a piezoelectric substrate, an electrode layer, a passivation layer and a suppression layer, the electrode layer, the passivation layer and the suppression layer are located on the piezoelectric substrate, the electrode layer comprises two interdigital electrodes oppositely arranged in the first direction, and each interdigital electrode comprises a bus bar and a plurality of electrode fingers; gaps are formed between the electrode fingers in different interdigital electrodes and the bus bars, and the passivation layer is embedded between the two interdigital electrodes in the first direction and covers the electrode fingers and the gaps; the suppression layer comprises two suppression units which are oppositely arranged in the first direction, and each suppression unit is connected with one bus bar to cover the gap and partially overlaps with at least one electrode finger located on the different side. According to the resonator, the suppression of a transverse mode is realized through the additionally arranged suppression layer structure, meanwhile, the quality factor is improved, the resonator can be suitable for various resonator structures and a wide frequency range, the durability and the linearity of the resonator are improved, the working stability of the resonator is further improved, and the service life of the resonator is further prolonged.

The invention relates to the field of electronic component preparation processes, in particular to a high-performance temperature compensation surface acoustic wave filter and a manufacturing method thereof. An interdigital transducer, wherein the interdigital transducer is located at one side of the piezoelectric substrate; the transition layer is located on the side, away from the piezoelectric substrate, of the interdigital transducer, and the transition layer covers the interdigital transducer and prevents metal elements of the interdigital transducer from diffusing outwards; the functional layer is located on the side, away from the interdigital transducer, of the transition layer, the functional layer covers an active area of a metal finger strip of the interdigital transducer to form a high-sound-velocity area, the end, away from the active area, of the metal finger strip of the interdigital transducer forms a low-sound-velocity area, and a sound velocity difference is formed between the high-sound-velocity area and the low-sound-velocity area; therefore, transverse mode clutters are suppressed; the temperature compensation layer is located on the side, away from the transition layer, of the functional layer, and the temperature compensation layer covers the functional layer and the piezoelectric substrate; lateral mode clutters in TC-SAW are suppressed, and metal diffusion is suppressed at the same time.

The invention provides a surface acoustic wave device structure and device, the surface acoustic wave device structure comprises a substrate and an IDT electrode, the IDT electrode is formed on the substrate and comprises two interdigital electrodes which are oppositely arranged, each interdigital electrode comprises a bus bar and a plurality of electrodes, and electrode fingers of different interdigital electrodes are arranged at intervals in a staggered manner. Each electrode finger at least comprises a first metal layer and a second metal layer which are stacked in sequence, and the thickness of the first metal layer in the first region is not smaller than the thickness of the first metal layer in the second region. The propagation velocity of the surface acoustic wave formed by excitation of the IDT electrode is greater than the propagation velocity of the surface acoustic wave formed by excitation of the IDT electrode in the first area, and the effect is equivalent to increase of a suppression load at the extension end of the electrode finger, so that the effect of suppressing a transverse mode can be achieved, and the Q value of the surface acoustic wave device is improved; and the processing technology requirement of the surface acoustic wave device structure is greatly reduced, and the technology cost is reduced.

The invention relates to a high-order transverse mode compression state preparation device based on optical parameter resonant cavity mode selection, and belongs to the technical field of quantum state light field generation. Fundamental frequency light and pump light output by the laser source generate a high-order transverse mode light field through the mode conversion module, and then the high-order transverse mode light field enters the optical parametric resonant cavity to be subjected to parametric down-conversion with the nonlinear crystal. The cavity length of the optical parametric resonant cavity is locked at the optimal pumping mode position corresponding to the high-order transverse mode compression state, so that resonance of an impurity mode in the optical parametric resonant cavity can be avoided, and the compression level of a high-order transverse mode light field is improved. Under injection of high-order transverse mode pump light, the pump mode is purified through the optical parametric resonant cavity of the annular structure, the compression level of a high-order transverse mode light field is enhanced, adjustment is easy, practicability is high, productization is easy, and wide application prospects are achieved in the fields of quantum space measurement, biological measurement, atomic force microscope detection and the like.

A line-field swept-source optical coherence tomography (OCT) system features a cat's-eye tunable laser that is free-space coupled to an interferometer. The laser employs a single angled facet (SAF) edge-emitting gain chip producing a beam with multiple spatial modes. By preserving these higher-order modes through free-space coupling—avoiding single-mode fiber— the system generates a line with a more uniform, top-hat intensity profile when projected onto a sample, such as a patient's retina. This profile mitigates the Gaussian power roll-off typically associated with single spatial mode beams, ensuring adequate signal-to-noise ratio across the line while adhering to optical safety limits. The laser cavity includes a thin-film interference bandpass filter mounted on an angle control actuator, allowing for wavelength sweeping by tilttuning the filter. The system integrates a line-scan sensor and is designed for manufacturability, offering improved imaging quality for ophthalmic diagnostics and other applications requiring high-resolution, cross-sectional imaging.

The invention discloses a staggered thickness type surface acoustic wave resonator, a filter and a manufacturing method thereof, and relates to the technical field of resonators / filters, the resonator comprises a substrate, a first electrode finger film layer and a second electrode finger film layer, the first electrode finger film layer is arranged on the substrate, one part of the second electrode finger film layer is arranged on the substrate, and the other part of the second electrode finger film layer is arranged on the substrate. The other part covers the first electrode finger film layer to form an overlapping area, and the first electrode finger film layer, the second electrode finger film layer and the overlapping area form a grid structure with the thickness changing in a staggered mode; according to the resonator, the filter and the manufacturing method thereof, the formed staggered grid structure forms different sound velocity regions between the interdigital electrode region and the bus bar, the propagation of a transverse mode is influenced, the transverse mode suppression effect is improved, the structure avoids the problem of large impedance caused by a thin metal film layer, and the performance of the resonator is improved. And a device with high resonant frequency has normal performance.

The invention relates to the technical field of lasers, and discloses an edge-emitting laser with a longitudinal mode and transverse mode selection function and a preparation method of the edge-emitting laser. The edge-emitting laser comprises a chip element, a mode modulation structure and an insulating layer, a ridge waveguide structure is arranged at the top of the chip element, and the mode modulation structure is located on one side of the ridge waveguide structure at the top of the chip element; the mode modulation structure comprises an annular cavity and an annular cavity electrode layer, and the annular cavity and the annular cavity electrode layer are spaced by an insulating layer; a P-type contact metal layer is arranged on the top of the chip element and located on the outer side of the ridge waveguide structure. According to the edge-emitting laser capable of selecting the longitudinal mode and the transverse mode at the same time, the mode modulation structure is arranged on the main ridge-shaped edge of laser feedback in the edge-emitting laser, flexible regulation and control of output of the longitudinal mode and the transverse mode in the ridge-shaped edge-emitting laser are achieved through the mode coupling principle, and external optical assemblies do not need to be added; the integration level and the compactness are good, and the technology is compatible with an existing laser.

An acoustic wave device has a multilayer piezoelectric substrate (MPS) structure and a multilayer interdigital transducer electrode (IDT). The multilayer piezoelectric substrate includes a piezoelectric layer over a support substrate. An additional (functional) layer can optionally be interposed between the piezoelectric layer and the support substrate, which can facilitate bonding between these layers and provide temperature compensation. The multilayer IDT is disposed over the piezoelectric layer and includes a first layer of a first material with higher density and a second layer of a different material with lower density. The interdigital transducer electrode also includes (mass loading) strips disposed over (e.g., adjacent, in contact with) the second layer, which advantageously facilitate suppression of transverse mode.

An antireflective vertical-cavity surface-emitting laser and a chip are provided. The laser comprises an active region (30) and Bragg reflection layers (10) located on two opposite sides of the active region (30), the active region (30) comprising at least five active layers (310) and a tunnel junction (330) located between the active layers (310), wherein a light anti-reflection storage cavity (40) is provided between the active region (30) and the Bragg reflection layer (10) on at least one side; the light anti-reflection storage cavity (40) is configured to increase the peak value of the intensity of a light field to be higher than that of the active region (30) and to store the light field energy; a current-limiting layer (320) is provided in the active region (30) or near the outer side of the active region (30), an optical aperture of the laser is located in a current injection region of the current-limiting layer (320); and the output laser is a single transverse mode laser.

A multilayer piezoelectric substrate acoustic wave device including an active region having a center region and a border region is disclosed. The acoustic wave device can include a support substrate, a piezoelectric layer over the support substrate, and an interdigital transducer electrode in electrical communication with the piezoelectric layer. The interdigital transducer electrode includes a bus bar and a finger extending from the bus bar. The finger in the border region has a first portion with a first width, a second portion with a second width between the center region and the first portion, and a third portion with a third width between the center region and the second portion. The finger in the center region has a fourth width. The first width and the third width are wider than the second width and the fourth width.

The invention relates to a quasi-differential wavefront segmentation double-beam interference device with a planar light path structural design, which has the structural characteristic of a non-closed optical path for transmitting a measurement light beam in a one-way manner. Space coherent light of a transverse mode vector filtering mechanism based on the Huygens principle / phased array principle instead of homologous transmission time coherent light is used as each light source, and a non-closed optical path is realized under the cooperation of a one-way transmission mode on a divided measuring light beam. The problem that the sum of the loop wavelength increment or the frequency increment of a closed path interference device is zero is solved, so that the purpose of measuring the first-level effect of anisotropic physical parameters of a measured object in a linear system is achieved, and the device is particularly suitable for immersion type online measurement. The optical elements have stable performance and sound self-adaptive mechanism and self-diagnosis capability through careful layout of the optical elements; and the method also has wide application prospects in basic physical research and novel navigation / positioning systems. The invention also provides a differential wavefront segmentation and semi-transparent and semi-reflective mirror beam combination interferometer device based on the planar light path structure design, and a wavefront segmentation interferometer device based on the planar light path structure design and provided with a pre-crossing area and a bending type one-way-two-way-common mode combination light path structure. The invention relates to a wavefront segmentation interferometer device of a one-way-two-way combined light path structure which is designed based on a planar light path structure and adopts polarization light splitting-beam combination, optical rotation processing of a reference light beam and original path returning, and a use method of an interference device.

The invention discloses a surface acoustic wave filter and a multiplexer surface acoustic wave filter, and the surface acoustic wave filter comprises a first piezoelectric substrate and a first interdigital transducer which is arranged on the first piezoelectric substrate. The first interdigital transducer comprises a first bus bar, a second bus bar, a plurality of first electrode fingers and a plurality of second electrode fingers, the first bus bar and the second bus bar are oppositely arranged, the first electrode fingers are led out from the first bus bar and extend towards the second bus bar, the second electrode fingers are led out from the second bus bar and extend towards the first bus bar, and the first electrode fingers and the second electrode fingers are arranged at intervals; the plurality of first electrode fingers and the plurality of second electrode fingers are mutually overlapped to form a first overlapping area, and the boundary shape of the first overlapping area conforms to a trigonometric function curve in the sound wave propagation direction; and the shapes of the first bus bar and the second bus bar are matched with the boundary shape of the first overlapping region. The technical effects that the transverse mode can be inhibited, and the small-size surface acoustic wave filter can be realized are achieved.