Surface acoustic wave resonator and filter

Abstract

The invention provides a surface acoustic wave resonator and a filter, the surface acoustic wave resonator comprises an interdigital region and a bus bar, the interdigital region comprises a first branch and a second branch, and the first branch and the second branch are respectively located at two sides of the interdigital region along a first direction; the first sub-part comprises at least one first sub-part and at least one second sub-part, and the first sub-part comprises a plurality of first short fingers and a plurality of first long fingers; the second sub-part comprises a plurality of second short fingers and a plurality of second long fingers; the second sub-part comprises at least one third sub-part and at least one fourth sub-part, and the third sub-part comprises a plurality of third short fingers and a plurality of third long fingers; the fourth sub-part comprises a plurality of fourth short fingers and a plurality of fourth long fingers; the bus bar extends along a third direction, and the value range of an included angle between the third direction and the second direction is 0 degree < theta < 20 degrees. According to the surface acoustic wave resonator, the slowness is changed after the surface acoustic wave enters the surface acoustic wave resonator, the transverse mode is inhibited, and the Q value of the surface acoustic wave resonator is improved.

Description

Technical Field

[0001] The present application relates to the technical field of resonators, and in particular to a surface acoustic wave resonator and a filter. Background Art

[0002] A surface acoustic wave resonator (SAWR) is a device that uses surface acoustic waves (SAW) to propagate and resonate on a crystal substrate. It consists of a pair of electrodes and a crystal substrate. The electrodes are used to excite and receive surface acoustic waves, and the crystal substrate is used to propagate surface acoustic waves.

[0003] A surface acoustic wave filter (SAW Filter) is a device that utilizes surface acoustic waves to propagate on a crystal substrate and achieve signal filtering. It consists of multiple surface acoustic wave resonators and couplers. By adjusting the frequency of the resonator and the coupling strength of the coupler, it can filter signals within a specific frequency range.

[0004] In surface acoustic wave filters, transverse parasitic modes refer to other undesirable vibration modes in addition to the main resonant mode during the propagation of surface acoustic waves. These parasitic modes may cause signal attenuation, distortion or interference, affecting the performance of the filter. Therefore, when designing surface acoustic wave filters, some measures need to be taken to suppress or eliminate these transverse parasitic modes to improve the performance and reliability of the filter. Summary of the invention

[0005] The present application provides a surface acoustic wave resonator and a filter, which are used to solve the problem that the lateral parasitic mode affects the performance and reliability of the filter.

[0006] In a first aspect, the present application provides a surface acoustic wave resonator, comprising an interdigital region and a bus bar;

[0007] The interdigital region includes a first sub-section and a second sub-section, and along a first direction, the first sub-section and the second sub-section are respectively located at two sides of the interdigital region;

[0008] The first subdivision includes at least one first subdivision and at least one second subdivision, the first subdivision includes a plurality of first short fingers and a plurality of first long fingers, the first short fingers and the first long fingers extend along the first direction and are alternately arranged in sequence along the second direction; the second subdivision includes a plurality of second short fingers and a plurality of second long fingers, the second short fingers and the second long fingers extend along the first direction and are alternately arranged in sequence along the second direction; the first direction intersects with the second direction;

[0009] The second subdivision includes at least one third subdivision and at least one fourth subdivision, the third subdivision includes a plurality of third short fingers and a plurality of third long fingers, the third short fingers and the third long fingers extend along the first direction and are alternately arranged in sequence along the second direction; the fourth subdivision includes a plurality of fourth short fingers and a plurality of fourth long fingers, the fourth short fingers and the fourth long fingers extend along the first direction and are alternately arranged in sequence along the second direction;

[0010] The busbars are arranged on both sides of the interdigital region and extend along a third direction. The value range of the angle θ0 between the third direction and the second direction is 0°<θ0<20°.

[0011] Preferably, the first division includes a first sub-divisions and b second sub-divisions, and the second division includes c third sub-divisions and d fourth sub-divisions;

[0012] Wherein, a, b, c and d are all positive integers, and a=c, b=d.

[0013] Preferably, the first division includes a plurality of first subdivisions and a plurality of second subdivisions, and the second division includes a plurality of third subdivisions and a plurality of fourth subdivisions;

[0014] The number of the first short fingers and the extension length along the second direction in any two first sub-divisions are the same, the number of the second short fingers and the extension length along the second direction in any two second sub-divisions are the same, the number of the third short fingers and the extension length along the second direction in any two third sub-divisions are the same, and the number of the fourth short fingers and the extension length along the second direction in any two fourth sub-divisions are the same.

[0015] Preferably, the first section includes at least two first sub-sections, and the first short fingers in the same first sub-section have the same extension length in the first direction; and at least two first short fingers in the first sub-section have different extension lengths in the first direction;

[0016] The second section includes at least two second sub-sections, and the second short fingers in the same second sub-section have the same extension length in the first direction; and at least two second short fingers in the second sub-section have different extension lengths in the first direction;

[0017] The second section includes at least two second sub-sections, and the second short fingers in the same second sub-section have the same extension length in the first direction; and at least two second short fingers in the second sub-section have different extension lengths in the first direction;

[0018] The second section includes at least two second sub-sections, and the second short fingers in the same second sub-section have the same extension length in the first direction; and at least two second short fingers in the second sub-section have different extension lengths in the first direction.

[0019] Preferably, the first division includes at least two first sub-divisions, and the extension lengths of the first short fingers in the first direction in the same first sub-division are the same; the extension lengths of the first short fingers in the first direction in at least two of the first sub-divisions are different; the second division includes at least two second sub-divisions, and the extension lengths of the second short fingers in the first direction in the same second sub-division are the same; the extension lengths of the second short fingers in the first direction in at least two of the second sub-divisions are different.

[0020] Preferably, ends of at least two of the first short fingers form a first straight line, and an angle formed by the first straight line and the second direction forms a first angle θ1, and a value range of the first angle θ1 is: 0°<θ1<20°;

[0021] The ends of at least two of the second short fingers form a second straight line, and the angle formed by the second straight line and the second direction forms a second angle θ2, and the value range of the second angle θ2 is: 0°<θ2<20°;

[0022] The ends of at least two of the third short fingers form a third straight line, and the angle formed by the third straight line and the second direction forms a third angle θ3, and the value range of the third angle θ3 is: 0°<θ3<20°;

[0023] The ends of at least two of the fourth short fingers form a fourth straight line, and the angle formed by the fourth straight line and the second direction forms a fourth angle θ4. The value range of the fourth angle θ4 is: 0°<θ4<20°.

[0024] Preferably, the first angle and the second angle satisfy the following relationship: θ1≠θ2.

[0025] Preferably, the first angle and the third angle satisfy the following relationship: θ1=θ3, and the second angle and the fourth angle satisfy the following relationship: θ2=θ4.

[0026] Preferably, the first angle and the third angle satisfy the following relationship: θ1≠θ3, and the second angle and the fourth angle satisfy the following relationship: θ2≠θ4.

[0027] Preferably, the first angle and the third angle satisfy the following relationship: θ1=θ3, and the second angle and the fourth angle satisfy the following relationship: θ2≠θ4.

[0028] In a second aspect, the present application further provides a filter, comprising the surface acoustic wave resonator described in any one of the first aspects.

[0029] The surface acoustic wave resonator and filter provided by the present application, the interdigital region includes a first division and a second division, and along the first direction, the first division and the second division are respectively located on both sides of the interdigital region; the first division includes at least one first sub-division and at least one second sub-division, the first sub-division includes a plurality of first short fingers and a plurality of first long fingers; the second sub-division includes a plurality of second short fingers and a plurality of second long fingers; the second division includes at least one third sub-division and at least one fourth sub-division, the third sub-division includes a plurality of third short fingers and a plurality of third long fingers; the fourth sub-division includes a plurality of fourth short fingers and a plurality of fourth long fingers; the bus bar extends along a third direction, and the angle between the third direction and the second direction is in the range of 0°<θ0<20°.

[0030] Tilted electrodes can reduce the electric field concentration at the electrode edge, thereby reducing electrical losses and improving the quality factor of the filter. Tilted electrodes help reduce the impact of temperature changes on filter characteristics. Due to the tilted design of the electrode, the electric field distribution is more uniform, and the impact of temperature-induced material property changes on the filter is reduced.

[0031] By adjusting the relationship among the first angle, the second angle, the third angle and the fourth angle, the extension lengths of the first short finger, the second short finger, the third short finger and the fourth short finger along the first direction are changed, thereby causing a sudden change in the aperture, so that the transverse wave propagating along the first direction is reflected back into the surface acoustic wave resonator, thereby reducing surface acoustic wave leakage, increasing the Q value, and improving the performance of the surface acoustic wave resonator.

[0032] By adjusting the angle between the third direction and the second direction, the slowness of the surface acoustic wave can be changed after entering the surface acoustic wave resonator provided by this embodiment, thereby forming energy confinement in the aperture direction, suppressing the transverse mode, and improving the Q value of the surface acoustic wave resonator. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions in the present application or the prior art, a brief introduction will be given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0034] FIG. 1( a ) is a structural schematic diagram 1 of a surface acoustic wave resonator provided in an embodiment of the present application;

[0035] FIG. 1( b ) is a schematic diagram of the structure of a surface acoustic wave resonator provided in an embodiment of the present application. Figure 2 ;

[0036] FIG. 1( c ) is a schematic diagram of the structure of a surface acoustic wave resonator provided in an embodiment of the present application. Figure 3 ;

[0037] Figure 2 A schematic diagram of the structure of another surface acoustic wave resonator provided in an embodiment of the present application;

[0038] Figure 3 A schematic diagram of the structure of another surface acoustic wave resonator provided in an embodiment of the present application;

[0039] Figure 4 A graph showing test results of the surface acoustic wave resonator provided in an embodiment of the present invention and a surface acoustic wave resonator in the prior art. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solutions and advantages of this application clearer, the technical solutions in this application will be clearly and completely described below in conjunction with the drawings in this application. Obviously, the described embodiments are part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0041] The terms "first", "second", etc. in the specification and claims of this application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchanged where appropriate, so that the embodiments described herein can be implemented in an order other than that illustrated or described herein.

[0042] Fig. 1 is a schematic diagram of the structure of a surface acoustic wave resonator provided in an embodiment of the present application. As shown in Fig. 1, a surface acoustic wave resonator includes an interdigital region 1 and a bus bar 2;

[0043] The interdigital region 1 includes a first sub-portion 11 and a second sub-portion 12. Along a first direction Y, the first sub-portion 11 and the second sub-portion 12 are respectively located at two sides of the interdigital region 1;

[0044] The first subdivision 11 includes at least one first subdivision 111 and at least one second subdivision 112, the first subdivision 111 includes a plurality of first short fingers 1111 and a plurality of first long fingers 1112, the first short fingers 1111 and the first long fingers 1112 extend along the first direction Y and are alternately arranged in sequence along the second direction X; the second subdivision 112 includes a plurality of second short fingers 1121 and a plurality of second long fingers 1122, the second short fingers 1121 and the second long fingers 1122 extend along the first direction Y and are alternately arranged in sequence along the second direction X; the first direction Y intersects with the second direction X;

[0045] The second division 12 includes at least one third sub-division 121 and at least one fourth sub-division 122, the third sub-division 121 includes a plurality of third short fingers 1211 and a plurality of third long fingers 1212, the third short fingers 1211 and the third long fingers 1212 extend along the first direction Y and are alternately arranged in sequence along the second direction X; the fourth sub-division 122 includes a plurality of fourth short fingers 1221 and a plurality of fourth long fingers 1222, the fourth short fingers 1221 and the fourth long fingers 1222 extend along the first direction Y and are alternately arranged in sequence along the second direction X. That is, the plurality of first short fingers 1111 and the plurality of first long fingers 1112 form a comb-like structure, the plurality of second short fingers 1121 and the plurality of second long fingers 1122 form a comb-like structure, the plurality of second short fingers 1121 and the plurality of second long fingers 1122 form a comb-like structure, the plurality of third short fingers 1211 and the plurality of third long fingers 1212 form a comb-like structure, and the plurality of fourth short fingers 1221 and the plurality of fourth long fingers 1222 form a comb-like structure. In addition, along the first direction Y, the first short fingers 1111 and the third long fingers 1212 are arranged in a one-to-one correspondence, the first long fingers 112 and the third short fingers 1211 are arranged in a one-to-one correspondence, the second short fingers 1121 and the fourth long fingers 1222 are arranged in a one-to-one correspondence, and the second long fingers 1122 and the fourth short fingers 1221 are arranged in a one-to-one correspondence.

[0046] The first short finger 1111 , the first long finger 1112 , the second short finger 1121 , the second long finger 1122 , the third short finger 1211 , the third long finger 1212 , the fourth short finger 1221 and the fourth long finger 1222 are all IDT electrodes, which can be used for acoustic-electric energy conversion.

[0047] It should be noted that the embodiment of the present invention does not specifically limit the number of the first short finger 1111, the first long finger 1112, the second short finger 1121, the second long finger 1122, the third short finger 1211, the third long finger 1212, the fourth short finger 1221 and the fourth long finger 1222.

[0048] Exemplarily, the first sub-division 111 , the second sub-division 112 , the third sub-division 121 , and the fourth sub-division 122 may be the smallest repeated divisions or may be non-repeated divisions.

[0049] The bus bar 2 is arranged on both sides of the interdigital area 1 and extends along the third direction, and the value range of the initial angle θ0 between the third direction and the second direction X is 0°<θ0<20°. When an AC signal of a certain frequency is applied to the bus bar 2, a surface acoustic wave can be generated in the interdigital area 1. The surface acoustic wave is mainly concentrated in the effective aperture area and mainly propagates along the second direction X, but there are also some surface acoustic waves, that is, transverse waves will propagate and leak along the first direction Y to one side of the bus bar. The inclined electrode can reduce the electric field concentration at the edge of the electrode, thereby reducing electrical loss and improving the quality factor of the filter. The inclined electrode helps to reduce the impact of temperature changes on the filtering characteristics. Due to the inclined design of the electrode, the electric field distribution is more uniform, and the impact of temperature-induced material property changes on the filter is reduced. By adjusting the angle between the third direction and the second direction X, the slowness of the surface acoustic wave can change after entering the surface acoustic wave resonator provided in this embodiment, thereby forming energy constraints in the aperture direction, suppressing the lateral mode, and improving the Q value of the surface acoustic wave resonator.

[0050] Exemplarily, along the second direction X, the surface acoustic wave resonator may further include reflection gratings respectively located on both sides of the interdigital region 1 , and the reflection gratings may be used to reflect the surface acoustic wave to prevent the surface acoustic wave from leaking.

[0051] Exemplarily, the IDT electrode and the reflector can be both disposed on a piezoelectric wafer. The materials of the IDT electrode and the reflector can be metals such as Cu, Al, Pt, Ti, and Cr, or alloys of the above metals, or a laminated composite structure. The piezoelectric wafer can include piezoelectric materials such as LiTaO3, LiNbO3, or quartz, as well as a composite multilayer wafer formed by bonding the above piezoelectric materials to SiO2, SiC, Si, or AlN. Exemplarily, the busbars and long fingers can be formed by one-time photolithography, and the material is generally Al or its alloy, wherein the material Cu is generally used in the temperature-compensated surface acoustic wave filter.

[0052] Preferably, the first division 11 includes a first sub-division 111 and b second sub-division 112, and the second division 12 includes c third sub-division 121 and d fourth sub-division 122;

[0053] Wherein, a, b, c and d are all positive integers, and a=c, b=d.

[0054] Exemplarily, the first division 11 shown in FIG1 includes 2 first subdivisions 111 and 2 second subdivisions 112, and the second division 12 includes 2 third subdivisions 121 and 2 fourth subdivisions 122, that is, a=c=2, b=d=2. It can be understood that FIG1 only shows the technical solution in which the number of first subdivisions 111 is equal to the number of second subdivisions 112. Exemplarily, the number of second subdivisions 112 may not be equal to the number of first subdivisions 111, such as a=c=2, b=d=4. The embodiment of the present invention does not specifically limit the number of first subdivisions 111 and second subdivisions 112.

[0055] Preferably, the first section 11 includes a plurality of first subsections 111 and a plurality of second subsections 112, and the second section 12 includes a plurality of third subsections 121 and a plurality of fourth subsections 122;

[0056] The number of the first short fingers 1111 and the extension length along the second direction in any two first subdivisions 111 are the same, the number of the second short fingers 1121 and the extension length along the second direction in any two second subdivisions 112 are the same, the number of the third short fingers 1211 and the extension length along the second direction in any two third subdivisions 121 are the same, and the number of the fourth short fingers 1221 and the extension length along the second direction in any two fourth subdivisions 122 are the same. The number of short fingers and the extension length along the second direction in any two identical subdivisions are the same, so that the overall structure has symmetry and consistency, and is easy to design and maintain.

[0057] Preferably, the first section 11 includes at least two first sub-sections 111, and the first short fingers 1111 in the same first sub-section 111 have the same extension length in the first direction Y; and the first short fingers 1111 in at least two first sub-sections 111 have different extension lengths in the first direction Y;

[0058] The second section 12 includes at least two second sub-sections 112, and the second short fingers 1121 in the same second sub-section 112 have the same extension length in the first direction Y; and at least two second short fingers 1121 in the second sub-section 112 have different extension lengths in the first direction Y;

[0059] The second section 12 includes at least two second sub-sections 112, and the second short fingers 1121 in the same second sub-section 112 have the same extension length in the first direction Y; and at least two second short fingers 1121 in the second sub-section 112 have different extension lengths in the first direction Y;

[0060] The second section 12 includes at least two second subsections 112, and the second short fingers 1121 in the same second subsection 112 have the same extension length in the first direction Y; at least two second short fingers 1121 in the second subsection 112 have different extension lengths in the first direction Y. The above arrangement can achieve aperture mutation, thereby suppressing shear waves, and can also achieve diversified designs of surface acoustic wave resonators.

[0061] Preferably, the first section 11 includes at least two first subsections 111, and the first short fingers 1111 in the same first subsection 111 have the same extension length in the first direction Y; at least two first short fingers 1111 in the first subsection 111 have different extension lengths in the first direction Y; the second section 12 includes at least two second subsections 112, and the second short fingers 1121 in the same second subsection 112 have the same extension length in the first direction Y; at least two second short fingers 1121 in the second subsection 112 have different extension lengths in the first direction Y. The above arrangement can achieve aperture mutation, thereby suppressing shear waves, and can achieve diversified designs of surface acoustic wave resonators on the one hand.

[0062] Preferably, ends of at least two of the first short fingers 1111 form a first straight line m1, and an angle formed by the first straight line m1 and the second direction X forms a first angle θ1, and a value range of the first angle θ1 is: 0°<θ1<20°;

[0063] The ends of at least two of the second short fingers 1121 form a second straight line m2, and the angle formed by the second straight line m2 and the second direction X forms a second angle θ2, and the value range of the second angle θ2 is: 0°<θ2<20°;

[0064] The ends of at least two of the third short fingers 1211 form a third straight line m3, and the angle formed by the third straight line m3 and the second direction X forms a third angle θ3, and the value range of the third angle θ3 is: 0°<θ3<20°;

[0065] The ends of at least two of the fourth short fingers 1221 form a fourth straight line m4. The angle formed by the fourth straight line m4 and the second direction X forms a fourth angle θ4. The value range of the fourth angle θ4 is: 0°<θ4<20°.

[0066] By changing the angles of the first angle, the second angle, the third angle and the fourth angle, a sudden aperture change can be caused so that the transverse wave propagating along the first direction is reflected back into the surface acoustic wave resonator, thereby reducing acoustic wave leakage, increasing the Q value, and thus improving the performance of the surface acoustic wave resonator.

[0067] Preferably, the first angle and the second angle satisfy the following relationship: θ1≠θ2.

[0068] Optionally, Figure 1 is a schematic diagram of the structure of a surface acoustic wave resonator provided by an embodiment of the present application. As shown in Figure 1, the first angle and the third angle satisfy the following relationship: θ1=θ3, and the second angle and the fourth angle satisfy the following relationship: θ2=θ4.

[0069] Optional, Figure 2 This is a schematic diagram of the structure of another surface acoustic wave resonator provided in an embodiment of the present application. Figure 2 As shown, the first angle and the third angle satisfy the following relationship: θ1≠θ3, and the second angle and the fourth angle satisfy the following relationship: θ2≠θ4.

[0070] Optional, Figure 3 A schematic diagram of the structure of another surface acoustic wave resonator provided in an embodiment of the present application. Figure 3 As shown, the first angle and the third angle satisfy the following relationship: θ1=θ3, and the second angle and the fourth angle satisfy the following relationship: θ2≠θ4.

[0071] By adjusting the relationship among the first angle, the second angle, the third angle and the fourth angle, the extension lengths of the first short finger, the second short finger, the third short finger and the fourth short finger along the first direction are changed, thereby causing a sudden change in the aperture, so that the transverse wave propagating along the first direction is reflected back into the surface acoustic wave resonator, thereby reducing surface acoustic wave leakage, increasing the Q value, and improving the performance of the surface acoustic wave resonator.

[0072] Figure 4 The test results of the surface acoustic wave resonator provided by the embodiment of the present invention and the surface acoustic wave resonator in the prior art are shown in FIG. Figure 4 , Figure 4 The horizontal axis in represents the frequency, Figure 4 The ordinate in the figure represents the admittance. The red curve represents the admittance curve of the surface acoustic wave resonator in the prior art, and the blue curve represents the admittance curve of the surface acoustic wave resonator provided in this embodiment. The left peak of the red curve and the blue curve is the resonance point, and the right peak is the anti-resonance point. Figure 4 It can be seen that the admittance curve of the surface acoustic wave resonator provided by the prior art has obvious lateral mode noise between the resonance point and the anti-resonance point, while the admittance curve obtained by using the surface acoustic wave resonator provided by this embodiment is very smooth between the resonance point and the anti-resonance point, and the lateral mode suppression effect is obvious.

[0073] Based on the same inventive concept, an embodiment of the present invention further provides a filter, including the surface acoustic wave resonator in the above embodiment. Therefore, the filter provided by the embodiment of the present invention also has the beneficial effects described in the above embodiment, which will not be repeated here.

[0074] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A surface acoustic wave resonator, characterized in that: including interdigital areas and bus bars; The interdigital region includes a first sub-section and a second sub-section, and along a first direction, the first sub-section and the second sub-section are respectively located at two sides of the interdigital region; The first subdivision includes at least one first subdivision and at least one second subdivision, the first subdivision includes a plurality of first short fingers and a plurality of first long fingers, the first short fingers and the first long fingers extend along the first direction and are alternately arranged in sequence along the second direction; the second subdivision includes a plurality of second short fingers and a plurality of second long fingers, the second short fingers and the second long fingers extend along the first direction and are alternately arranged in sequence along the second direction; the first direction intersects with the second direction; The second subdivision includes at least one third subdivision and at least one fourth subdivision, the third subdivision includes a plurality of third short fingers and a plurality of third long fingers, the third short fingers and the third long fingers extend along the first direction and are alternately arranged in sequence along the second direction; the fourth subdivision includes a plurality of fourth short fingers and a plurality of fourth long fingers, the fourth short fingers and the fourth long fingers extend along the first direction and are alternately arranged in sequence along the second direction; The busbars are arranged on both sides of the interdigital region and extend along a third direction. The value range of the angle θ0 between the third direction and the second direction is 0°<θ0<20°.

2. The surface acoustic wave resonator according to claim 1, characterized in that: The first division includes a first sub-divisions and b second sub-divisions, and the second division includes c third sub-divisions and d fourth sub-divisions; Wherein, a, b, c and d are all positive integers, and a=c, b=d.

3. The surface acoustic wave resonator according to claim 1, characterized in that: The first division includes a plurality of first subdivisions and a plurality of second subdivisions, and the second division includes a plurality of third subdivisions and a plurality of fourth subdivisions; The number of the first short fingers and the extension length along the second direction in any two first sub-divisions are the same, the number of the second short fingers and the extension length along the second direction in any two second sub-divisions are the same, the number of the third short fingers and the extension length along the second direction in any two third sub-divisions are the same, and the number of the fourth short fingers and the extension length along the second direction in any two fourth sub-divisions are the same.

4. The surface acoustic wave resonator according to claim 1, characterized in that: The first section includes at least two first sub-sections, and the first short fingers in the same first sub-section have the same extension length in the first direction; and at least two first short fingers in the first sub-section have different extension lengths in the first direction; The second section includes at least two second sub-sections, and the second short fingers in the same second sub-section have the same extension length in the first direction; and at least two second short fingers in the second sub-section have different extension lengths in the first direction; The second section includes at least two second sub-sections, and the second short fingers in the same second sub-section have the same extension length in the first direction; and at least two second short fingers in the second sub-section have different extension lengths in the first direction; The second section includes at least two second sub-sections, and the second short fingers in the same second sub-section have the same extension length in the first direction; and at least two second short fingers in the second sub-section have different extension lengths in the first direction.

5. The surface acoustic wave resonator according to claim 1, characterized in that: The first division includes at least two first sub-divisions, and the extension lengths of the first short fingers in the first direction in the same first sub-division are the same; the extension lengths of the first short fingers in the first direction in at least two of the first sub-divisions are different; the second division includes at least two second sub-divisions, and the extension lengths of the second short fingers in the first direction in the same second sub-division are the same; the extension lengths of the second short fingers in the first direction in at least two of the second sub-divisions are different.

6. The surface acoustic wave resonator according to claim 1, characterized in that: The ends of at least two of the first short fingers form a first straight line, and the angle formed by the first straight line and the second direction forms a first angle θ1, and the value range of the first angle θ1 is: 0°<θ1<20°; The ends of at least two of the second short fingers form a second straight line, and the angle formed by the second straight line and the second direction forms a second angle θ2, and the value range of the second angle θ2 is: 0°<θ2<20°; The ends of at least two of the third short fingers form a third straight line, and the angle formed by the third straight line and the second direction forms a third angle θ3, and the value range of the third angle θ3 is: 0°<θ3<20°; The ends of at least two of the fourth short fingers form a fourth straight line, and the angle formed by the fourth straight line and the second direction forms a fourth angle θ4. The value range of the fourth angle θ4 is: 0°<θ4<20°.

7. The surface acoustic wave resonator according to claim 1, characterized in that: The first angle and the second angle satisfy the following relationship: θ1≠θ2.

8. The surface acoustic wave resonator according to claim 7, characterized in that: The first angle and the third angle satisfy the following relationship: θ1=θ3, and the second angle and the fourth angle satisfy the following relationship: θ2=θ4.

9. The surface acoustic wave resonator according to claim 7, characterized in that: The first angle and the third angle satisfy the following relationship: θ1≠θ3, and the second angle and the fourth angle satisfy the following relationship: θ2≠θ4.

10. The surface acoustic wave resonator according to claim 7, characterized in that: The first angle and the third angle satisfy the following relationship: θ1=θ3, and the second angle and the fourth angle satisfy the following relationship: θ2≠θ4.

11. A filter, characterized in that: The invention comprises the surface acoustic wave resonator according to any one of claims 1 to 10.

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