Full-range silicon microphone with tic-tac-toe bracing

Abstract

A full-band silicon microphone with a tic-tac-toe sound beam, comprising a sensor, a sound cavity and a circuit board; the sensor comprises a diaphragm and a silicon back plate; a first and a second groove are formed on at least one side of the surface of the diaphragm, the two grooves are cross-shaped and interpenetrate each other, and the surface of the diaphragm is equally divided into four resonance areas; the diaphragm is also provided with a sound beam assembly in the center of the same side surface where the two grooves are provided, comprising a plurality of strip-shaped sound beam components, the strip-shaped sound beam components are arranged in pairs on both sides of the first groove and on both sides of the second groove; the two grooves form sound tunnels on the surface of the diaphragm respectively. The present invention changes the diaphragm from the previous free vibration mode to the current standard vibration mode, and solves the problem that the silicon microphone cannot effectively resonate the full-band sound details from the perspective of vibration and resonance, so that the silicon microphone can effectively resonate in the full-band and achieve a high-fidelity effect. Practice has proved that the improved design scheme has outstanding substantive characteristics and significant technical progress, and has achieved obvious technical effects.

Description

Technical Field

[0001] The invention relates to a silicon microphone, in particular to a full-band silicon microphone with a tic-tac-toe-shaped sound beam. Background Art

[0002] Silicon microphones, also known as MEMS (Micro-Electro-Mechanical System) microphones, are microphones manufactured based on MEMS technology. They have considerable advantages over ECM in terms of miniaturization, performance, reliability, environmental tolerance, cost and mass production capacity, and have quickly occupied the market of consumer electronic products such as mobile phones, headphones, PDAs, MP3s and hearing aids.

[0003] Silicon microphones are composed of MEMS sensors, ASIC chips, sound chambers, and circuit boards with RF suppression circuits. MEMS sensors are micro-capacitors consisting of a diaphragm and a silicon back plate, which can convert sound pressure changes into capacitance changes, and then the ASIC chip converts the capacitance changes into electrical signals, realizing "sound-to-electricity" conversion.

[0004] Common problems with traditional silicon microphones are:

[0005] When the diaphragm of the silicon microphone receives sound waves from an external sound source, it has an inherent resonant frequency. If it exceeds a certain range of the resonant frequency area, the treble and bass areas will not be able to resonate effectively, resulting in the sound quality of the received sound being converted from "sound to electricity" and then restored from "electricity to sound". The treble area is not bright, and the bass area is not thick and round enough, which leads to poor sound fidelity. The main reason is that the current diaphragm cannot meet the requirements of good broadband vibration from the treble area to the bass area, that is, it cannot adapt to the wide frequency change resonance and vibration of the treble area, mid-range area and bass area at the same time. Therefore, it is impossible to collect all the sound details of the full frequency band when receiving sound. In summary, the structural design of traditional silicon microphones is unreasonable, which is not conducive to the diaphragm to exert good sound wave vibration from the treble area to the bass area.

[0006] Therefore, how to solve the above-mentioned deficiencies in the prior art has become a subject to be studied and solved by the present invention. Summary of the invention

[0007] The purpose of the present invention is to provide a full-band silicon microphone with a tic-tac-toe sound beam.

[0008] In order to achieve the above object, the technical solution adopted by the present invention is:

[0009] A full-band silicon microphone with a tic-tac-toe sound beam comprises a sensor, a sound cavity and a circuit board; the sensor is located in the sound cavity, and the sensor comprises a diaphragm and a silicon back plate;

[0010] A first groove and a second groove are formed on at least one side surface of the diaphragm, the first groove and the second groove are cross-intersected and interpenetrated on the surface of the diaphragm, the intersection point is located at the center of the diaphragm, and the surface of the diaphragm is equally divided into four resonance areas;

[0011] The diaphragm is also provided with a sound beam assembly at the center of the same side surface where the first groove and the second groove are provided, and the sound beam assembly includes a plurality of strip-shaped sound beam components, and the strip-shaped sound beam components are arranged in pairs on both sides of the first groove and on both sides of the second groove;

[0012] The first groove and the second groove form sound tunnels on the surface of the diaphragm respectively.

[0013] The relevant contents in the above technical solution are explained as follows:

[0014] 1. In the above scheme, the “first groove and the second groove are cross-shaped on the surface of the diaphragm and interpenetrate each other”, which helps to quickly transmit the vibration of the sound source to the surroundings of the diaphragm through the cross-shaped sound tunnel (i.e., the sound tunnel) formed by the two grooves.

[0015] 2. In the above solution, the intersection of the first groove and the second groove is located at the center of the diaphragm, and this design can improve the resonance response rate of the diaphragm.

[0016] 3. In the above scheme, a connecting beam is provided between two adjacent strip-shaped sound beam components, and the connecting beam spans above the first groove and the second groove, forming the sound beam component in a tic-tac-toe shape; and each of the connecting beams is located in the central area of ​​the diaphragm surface. With this design, the central area of ​​the diaphragm can be strengthened.

[0017] 4. In the above scheme, the diaphragm is divided into a high-pitched area in the outer section, a mid-pitched area in the middle section, and a low-pitched area in the inner section from the sound emission band; wherein the wall thickness of the diaphragm gradually increases from the outer to the inner side, the wall thickness of the low-pitched area is greater than that of the mid-pitched area, and the wall thickness of the mid-pitched area is greater than that of the high-pitched area; the sound beam assembly is located in the low-pitched area.

[0018] With this design, by setting the thicker bass area close to the center, the bass area of ​​the diaphragm can be more easily resonated with the low-frequency vibrations with lower frequency and larger amplitude, so that the restored sound will produce a thicker and rounder bass; by setting the thinner treble area far away from the center, the treble area of ​​the diaphragm can be more easily resonated with the high-frequency vibrations with higher frequency and smaller amplitude, so that the restored sound will produce a more transparent and bright treble, thereby enabling the silicon microphone to effectively resonate in the entire frequency band, so that the timbre and sound quality of the restored sound are effectively improved, achieving a high-fidelity effect.

[0019] 5. In the above solution, the inner end thickness of the strip-shaped sound beam component is greater than the outer end thickness. With this design, the central area of ​​the diaphragm can be strengthened.

[0020] 6. In the above solution, the first groove and the second groove are both arc-shaped grooves, which can minimize the thickness change of the diaphragm and avoid affecting the resonance and vibration of the diaphragm.

[0021] 7. In the above solution, the lengths of the first groove and the second groove are both smaller than the horizontal width of the diaphragm, and smooth transition surfaces are provided between the outer ends of the first groove and the second groove and the surface of the diaphragm.

[0022] The working principle and advantages of the present invention are as follows:

[0023] The present invention discloses a full-band silicon microphone with a cross-shaped sound beam, comprising a sensor, a sound cavity and a circuit board; the sensor comprises a diaphragm and a silicon back plate; a first groove and a second groove are formed on at least one side surface of the diaphragm, the two grooves are cross-shaped and interpenetrate each other, and the surface of the diaphragm is equally divided into four resonance areas; the diaphragm is also provided with a sound beam assembly at the center of the same side surface where the two grooves are provided, comprising a plurality of strip-shaped sound beam components, the strip-shaped sound beam components are arranged in pairs on both sides of the first groove and on both sides of the second groove; the two grooves respectively form sound tunnels on the surface of the diaphragm.

[0024] Compared with the prior art, in order to solve the problem that the existing silicon microphone cannot take into account the high, middle and low frequency ranges while having good resonance when receiving sound, the present invention improves the existing silicon microphone, especially the diaphragm design in the silicon microphone. Specifically, it is embodied in the following aspects: first, a sound beam assembly is set on the surface of the diaphragm; second, a cross-shaped groove is opened on the surface of the diaphragm, and the cross-shaped groove forms a cross-shaped sound tunnel on the surface of the diaphragm.

[0025] Aiming at the problem that the high-pitched area of ​​the sound restored by the existing silicon microphone after receiving the sound is not bright, and the bass area is not thick and round enough, the present invention conducts in-depth discussion and research on the design and vibration mechanism of the silicon microphone, and finds out that the main reason for the poor vibration of the high-pitched area and the bass area of ​​the existing silicon microphone is due to the unreasonable design of the diaphragm. Based on this, the inventor broke the constraints of the previous silicon microphone composition design and boldly proposed the improved design scheme of the present invention. This improved design scheme changes the diaphragm from the previous free vibration mode to the current standard vibration mode, and solves the problem that the silicon microphone cannot effectively resonate the full-band sound details when receiving sound from the perspective of vibration and resonance, resulting in the high-pitched area of ​​the restored sound not being bright, and the bass area not being thick and round enough. Practice has proved that the improved design scheme has outstanding substantive characteristics and significant technical progress, and has achieved obvious technical effects.

[0026] Due to the application of the above technical solution, the present invention has the following advantages and effects compared with the diaphragm of the existing silicon microphone:

[0027] 1. The present invention sets a sound beam assembly on the surface of the diaphragm. Since the bass has a larger amplitude and lower frequency than the treble, the bass resonance is concentrated in the area close to the center of the diaphragm, and the treble resonance is concentrated in the surrounding edge areas of the diaphragm. The strength of the central area of ​​the diaphragm is strengthened, which plays an important role in improving the high-fidelity bass timbre and sound quality. Since the thickness of the diaphragm is a gradual thickness structure with thick central area and thin surrounding areas (i.e., thin outside and thick inside), the strength of the central area of ​​the diaphragm is strengthened, and the thickness difference between the central area of ​​the diaphragm and the surrounding edge areas is relatively changed, which can also play a beneficial role in improving the high-fidelity treble timbre and sound quality.

[0028] 2. The present invention provides a cross-shaped groove on the surface of the diaphragm, which actually forms a cross-shaped sound tunnel on the diaphragm. After the diaphragm receives the vibration, the sound is quickly transmitted to the edges around the diaphragm through the cross-shaped sound tunnel (i.e., the sound tunnel), which plays a key role in improving the resonance of the treble region and can better receive the details of the treble band of the sound.

[0029] 3. The present invention divides the diaphragm into four equal resonance areas through the design of the sound beam assembly and the cross-shaped groove. When the silicon microphone is working, the vibration is first transmitted to the central area of ​​the diaphragm, and then transmitted to each resonance area through the sound tunnel, and resonance and vibration are generated, thereby amplifying the vibration of the external sound source into the resonance of the diaphragm. Each resonance area can generate one sound wave amount, plus one original sound wave amount, a total of five sound waves. The sound wave amount is the number of sound waves, and the sound wave amount directly affects the timbre and sound quality of the diaphragm. Therefore, the design of the present invention can significantly improve the timbre and sound quality of the high and low pitch areas.

[0030] 4. The sound beam assembly and the groove of the present invention can be arranged on the upper surface of the diaphragm, can also be arranged on the lower surface of the diaphragm, and can also be arranged on both the upper and lower surfaces of the diaphragm. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Attached Figure 1 This is a schematic diagram of the structure of the silicon microphone of the present invention (the sound inlet is located on the upper side);

[0032] Attached Figure 2 This is a schematic diagram of the structure of the silicon microphone of the present invention (the sound inlet is located at the bottom);

[0033] Attached Figure 3 Schematic diagram of the structure of the diaphragm in an embodiment of the present invention (without connecting beam);

[0034] Attached Figure 4 for Figure 3 A top view of

[0035] Attached Figure 5 A schematic diagram of an embodiment of the present invention in which the sound beam assembly is disposed on the upper surface of the diaphragm (without a connecting beam);

[0036] Attached Figure 6 This is a schematic diagram of an embodiment of the present invention in which the sound beam assembly is disposed on both the upper and lower surfaces of the diaphragm (without a connecting beam);

[0037] Attached Figure 7 is a schematic diagram of the structure of the diaphragm in an embodiment of the present invention (with a connecting beam);

[0038] Attached Figure 8 for Figure 7 A top view of

[0039] Attached Fig. 9 It is a schematic diagram of an embodiment of the present invention in which the sound beam assembly is arranged on the upper surface of the diaphragm (with a connecting beam);

[0040] Attached Fig.10 This is a schematic diagram of an embodiment of the present invention in which the sound beam assembly is simultaneously disposed on the upper and lower surfaces of the diaphragm (with a connecting beam).

[0041] In the above figures: 1. sound cavity; 2. circuit board; 3. diaphragm; 4. sound beam assembly; 4a. strip sound beam component; 4b. connecting beam; 5. shell; 6. sound inlet hole; 7. first groove; 8. second groove; 9. silicon back plate; 10. resonance area. DETAILED DESCRIPTION

[0042] The present invention will be further described below in conjunction with the accompanying drawings and embodiments:

[0043] Embodiment: The present invention will be clearly described below with diagrams and detailed descriptions. After understanding the embodiments of the present invention, any person skilled in the art can make changes and modifications based on the techniques taught by the present invention without departing from the spirit and scope of the present invention.

[0044] The terms used herein are only for describing specific embodiments and are not intended to be limiting of the present invention. Singular forms such as "a", "this", "here", "this" and "the" as used herein also include plural forms.

[0045] As used herein, “connected” or “positioned” may refer to two or more components or devices being in direct physical contact with each other, or being in indirect physical contact with each other, or may refer to two or more components or devices operating or moving with each other.

[0046] The terms “include,” “including,” “have,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0047] The terms used in this document generally have the ordinary meaning of each term used in this field, in the context of the case and in the specific context, unless otherwise noted. Certain terms used to describe the present invention will be discussed below or elsewhere in this specification to provide additional guidance to those skilled in the art in describing the present invention.

[0048] The terms "upper" and "lower" used in this article are directional terms. In this case, they are only used to illustrate the positional relationship between the structures, and are not used to limit the protection plan of this case and the specific direction during actual implementation.

[0049] See attached Figures 1 to 4 As shown, a full-band silicon microphone with a tic-tac-toe sound beam comprises a MEMS sensor, a sound cavity 1 and a circuit board 2 with an RF suppression circuit; the MEMS sensor is located in the sound cavity 1, and the MEMS sensor comprises a diaphragm 3 and a silicon back plate 9; the two are arranged at an interval, and the silicon back plate 9 is arranged corresponding to a sound inlet hole 6 on the silicon microphone shell 5.

[0050] A first groove 7 and a second groove 8 are formed on the lower surface of the diaphragm 3 . The two grooves 7 and 8 form a transverse sound tunnel and a longitudinal sound tunnel on the lower surface of the diaphragm 3 , respectively.

[0051] The first groove 7 and the second groove 8 are cross-intersecting and interpenetrating on the surface of the diaphragm 3, and the intersection is located at the center of the diaphragm 3, which helps to quickly transmit the vibration of the sound source to the surroundings of the diaphragm 3 through the cross-shaped sound tunnel (i.e., the sound tunnel) formed by the two grooves 7 and 8. The first groove 7 and the second groove 8 divide the surface of the diaphragm 3 into four resonance areas 10.

[0052] By providing a cross-shaped groove on the lower surface of the diaphragm 3, the cross-shaped groove actually forms a cross-shaped sound tunnel on the surface of the diaphragm 3, and the area close to the center collects the vibration of the external sound source, and then quickly transmits it to the edges around the diaphragm 3 through the cross-shaped sound tunnel, which plays a key role in improving the resonance of the high-pitched area. At the same time, by equally dividing the diaphragm 3 into four resonance areas 10, the vibration can be transmitted to the four resonance areas 10 through the sound tunnel and generate resonance, which can significantly improve the timbre of the bass and high-pitched areas.

[0053] A sound beam assembly 4 is further provided in the center of the lower surface of the diaphragm 3 . The sound beam assembly 4 includes a plurality of strip-shaped sound beam components 4 a . The strip-shaped sound beam components 4 a are arranged in pairs on both sides of the first groove 7 and on both sides of the second groove 8 .

[0054] By arranging the sound beam assembly 4 on the lower surface of the diaphragm 3, since the bass has a larger amplitude and lower frequency than the treble, the bass resonance is concentrated in the area near the center of the diaphragm 3, and the treble resonance is concentrated in the peripheral edge areas of the diaphragm 3, thereby strengthening the strength of the central area of ​​the diaphragm 3, which plays an important role in improving the high-fidelity bass timbre and sound quality. Since the thickness of the diaphragm 3 is a gradual thickness structure in which the central area is thick and the surrounding areas are thin (i.e., the outer area is thin and the inner area is thick), the strength of the central area of ​​the diaphragm 3 is strengthened, and the thickness difference between the central area of ​​the diaphragm 3 and the peripheral edge areas is relatively changed, which can also play a beneficial role in improving the high-fidelity treble timbre and sound quality.

[0055] Preferably, Figure 7 , 8 As shown, a connecting beam 4b is provided between two adjacent strip-shaped sound beam components 4a, and the connecting beam 4b spans over the first groove 7 and the second groove 8, forming the sound beam assembly 4 in a tic-tac-toe shape; and each of the connecting beams 4b is located in the central area of ​​the surface of the diaphragm 3. The four connecting beams 4b form a "mouth"-shaped reinforcement structure, which can further strengthen the bass area in the center of the diaphragm 3, so as to further enhance the bass resonance effect of the diaphragm.

[0056] Preferably, the diaphragm 3 is divided into a high-pitched area in the outer section, a mid-pitched area in the middle section, and a low-pitched area in the inner section from the sound emission band. The wall thickness of the diaphragm 3 gradually increases from the outside to the inside, and the wall thickness of the low-pitched area is greater than that of the mid-pitched area, and the wall thickness of the mid-pitched area is greater than that of the high-pitched area; the sound beam assembly 4 is located in the low-pitched area, which can increase the load in the middle of the diaphragm 3.

[0057] With this design, by setting the thicker bass area close to the center, the bass area of ​​the diaphragm 3 can be more easily resonated with the low-frequency vibration with a lower frequency and a larger amplitude, so that the restored sound emits a thicker and rounder bass; and by setting the thinner treble area far from the center, the treble area of ​​the diaphragm 3 can be more easily resonated with the high-frequency vibration with a higher frequency and a smaller amplitude, so that the restored sound emits a more transparent and bright treble, thereby enabling the silicon microphone to effectively resonate in the entire frequency band, so that the timbre and sound quality of the restored sound are effectively improved, achieving a high-fidelity effect.

[0058] Preferably, the inner end thickness of the strip-shaped sound beam member 4a is greater than the outer end thickness. With this design, the central area of ​​the diaphragm 3 can be strengthened.

[0059] The first groove 7 and the second groove 8 are both arc-shaped grooves, which can minimize the thickness change of the diaphragm 3 to avoid affecting the resonance and vibration of the diaphragm 3. The lengths of the first groove 7 and the second groove 8 are both smaller than the horizontal width of the diaphragm 3, and smooth transition surfaces are provided between the outer ends of the first groove 7 and the second groove 8 and the surface of the diaphragm 3, so that the vibration is transmitted to the periphery of the diaphragm 3 more evenly.

[0060] The following is an explanation of other implementations and structural changes of the present invention:

[0061] 1. In the above embodiments, the silicon microphone shown in the figure is only used for illustration, and its structure is not used to limit the protection scope of the present invention. Other silicon microphones with similar structures should be covered within the protection scope of the present invention if they adopt the technical features of the present invention.

[0062] 2. In the above embodiments, the number of the sound beam assemblies 4 is not limited to one group, and may also be multiple groups arranged in parallel or other designs that help to strengthen the load on the middle part of the diaphragm 3, which is easily understood and accepted by those skilled in the art.

[0063] 3. In the above embodiments, the sound beam assembly 4 and the two grooves 7 and 8 may be located on the lower surface of the diaphragm 3 (such as Figure 4 , 8 ), or may be located on the upper surface of the diaphragm 3 (as shown Figure 5 , 9 As shown in FIG. 1 ), it can also be arranged on both the upper and lower surfaces of the diaphragm 3 (as shown in FIG. Figure 6 , 10 as shown).

[0064] 4. In the above embodiments, the strip-shaped sound beam members 4a can be straight strips as shown in the figure, and are combined in pairs at 90 degrees and arranged in pairs on both sides of the first groove 7 and both sides of the second groove 8.

[0065] Alternatively, the strip-shaped sound beam component 4 a may also have an arc and include two straight sides, and the straight sides of two adjacent strip-shaped sound beam components 4 a are arranged in pairs on both sides of the first groove 7 and the second groove 8 .

[0066] 5. In the above embodiments, the first groove 7 and the second groove 8 are both arc-shaped grooves. However, the present invention is not limited thereto, and the grooves may be designed into other shapes, such as V-shaped, U-shaped, W-shaped and other concave structures. This is easily understood and accepted by those skilled in the art.

[0067] 6. In the above embodiments, the diaphragm 3 may be a silicon diaphragm (such as single crystal silicon, polycrystalline silicon, silicon nitride plus electrodes), or may be a diaphragm of other materials with the same or similar functions and effects.

[0068] Compared with the prior art, in order to solve the problem that the existing silicon microphone cannot take into account the high, middle and low frequency ranges while having good resonance timbre when receiving sound, the present invention improves the existing silicon microphone, especially the diaphragm design in the silicon microphone. Specifically, it is embodied in the following aspects: first, a sound beam assembly is set on the surface of the diaphragm; second, a cross-shaped groove is opened on the surface of the diaphragm, and the cross-shaped groove forms a cross-shaped sound tunnel on the surface of the diaphragm.

[0069] Aiming at the problem that the high-pitched area of ​​the sound restored by the existing silicon microphone after receiving the sound is not bright, and the bass area is not thick and round enough, the present invention conducts in-depth discussion and research on the design and sound-generating mechanism of the silicon microphone, and finds out that the main reason for the poor timbre of the high-pitched area and the bass area of ​​the existing silicon microphone is due to the unreasonable design of the diaphragm. Based on this, the inventor broke the constraints of the previous silicon microphone component design and boldly proposed the improved design scheme of the present invention. This improved design scheme changes the diaphragm from the previous free vibration mode to the current standard vibration mode, and solves the problem that the high-pitched area of ​​the sound restored by the silicon microphone after receiving the sound is not bright, and the bass area is not thick and round enough from the perspective of vibration and resonance, and improves the fidelity of the sound in each frequency band. Practice has proved that the improved design scheme has outstanding substantive characteristics and significant technical progress, and has achieved obvious technical effects.

[0070] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with the technology to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A full-band silicon microphone with a tic-tac-toe sound beam, characterized in that: It comprises a sensor, a sound cavity (1) and a circuit board (2); the sensor is located in the sound cavity (1), and the sensor comprises a diaphragm (3) and a silicon back plate (9); A first groove (7) and a second groove (8) are formed on at least one side surface of the diaphragm (3); the first groove (7) and the second groove (8) are cross-intersecting and mutually interpenetrating on the surface of the diaphragm (3); the intersection point is located at the center of the diaphragm (3), thereby dividing the surface of the diaphragm (3) into four equal resonance areas (10); The diaphragm (3) is also provided with a sound beam assembly (4) at the center of the same side surface where the first groove (7) and the second groove (8) are provided, and the sound beam assembly (4) comprises a plurality of strip-shaped sound beam components (4a), and the strip-shaped sound beam components (4a) are arranged in pairs on both sides of the first groove (7) and on both sides of the second groove (8); The first groove (7) and the second groove (8) respectively form sound tunnels on the surface of the diaphragm (3).

2. The full-band silicon microphone with a tic-tac-toe beam according to claim 1, characterized in that: A connecting beam (4b) is provided between two adjacent strip-shaped sound beam components (4a), and the connecting beam (4b) spans above the first groove (7) and the second groove (8), forming the sound beam assembly (4) in a tic-tac-toe shape; and each of the connecting beams (4b) is located in a central area of ​​the surface of the diaphragm (3).

3. The full-band silicon microphone with a tic-tac-toe beam according to claim 1, characterized in that: The diaphragm (3) is divided into an outer high-pitched area, a middle-pitched area, and an inner low-pitched area in terms of the sound emission band; The wall thickness of the diaphragm (3) gradually increases from the outside to the inside, the wall thickness of the bass region is greater than the wall thickness of the mid-range region, and the wall thickness of the mid-range region is greater than the wall thickness of the treble region; The sound beam assembly (4) is located in the bass region.

4. The full-band silicon microphone with a tic-tac-toe sound beam according to claim 1, characterized in that: The inner end thickness of the strip-shaped sound beam component (4a) is greater than the outer end thickness.

5. The full-band silicon microphone with a tic-tac-toe sound beam according to claim 1, characterized in that: Each of the first grooves (7) and the second grooves (8) is an arc-shaped groove.

6. The full-band silicon microphone with a tic-tac-toe sound beam according to claim 1, characterized in that: The lengths of the first groove (7) and the second groove (8) are both smaller than the horizontal width of the diaphragm (3); and smooth transition surfaces are provided between the outer ends of the first groove (7) and the second groove (8) and the surface of the diaphragm (3).

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