A high reliability directional sound screen

Abstract

The utility model discloses a high-reliability directional sound-emitting screen, comprising a vibration layer, a non-vibration layer, a pattern layer and an insulating layer. The frames of the vibration layer and the non-vibration layer are bonded together. After the vibration layer and the non-vibration layer frames are bonded together, an air gap required for the vibration layer to vibrate up and down and emit sound is formed between the pattern layer and the non-vibration layer. The insulating layer is located between the pattern layer and the first conductive layer or between the pattern layer and the second conductive layer, and the insulating layer includes an antistatic layer. The utility model replaces the existing ink insulating medium layer of the directional sound-emitting screen with an antistatic layer with stable performance, so that it is not easy to lose charge, and the accumulation of static electricity on its surface can be reduced, thereby greatly reducing the influence of the charge generated by air ionization on the air partial pressure, thereby improving the reliability and sound pressure of the directional sound-emitting screen.

Description

Technical Field

[0001] The utility model relates to the technical field of directional sound emission, in particular to a high-reliability directional sound emission screen. Background Art

[0002] Electrostatic thin film ultrasonic transducer is also called capacitive thin film ultrasonic transducer. It uses the electrostatic force generated by the upper and lower electrodes to drive the film to vibrate, thereby radiating ultrasonic waves.

[0003] The common electrostatic thin film ultrasonic transducer structure generally includes a vibration substrate layer, a top electrode, a pattern layer, an insulating layer, a bottom electrode and a non-vibration substrate layer arranged in sequence from top to bottom, and an air gap is formed between the top electrode and the insulating layer. A DC bias voltage Vdc and an AC voltage Vac are passed between the top electrode and the bottom electrode to drive the vibration substrate layer to vibrate and generate sound.

[0004] However, when the input voltage increases, the air in the air gap will be ionized, which will increase the conductivity of the air, resulting in a decrease in the partial pressure of the air, which in turn will cause a decrease in the ultrasonic sound pressure radiated by the electrostatic thin film ultrasonic transducer, causing the performance of the transducer to decline.

[0005] Therefore, how to reduce the impact of air ionization on the reliability and sound pressure of electrostatic thin film ultrasonic transducers is a problem that needs to be solved. Utility Model Content

[0006] The utility model aims to provide a high-reliability directional sound-emitting screen which can effectively reduce the influence of air ionization on the reliability and sound pressure of the directional sound-emitting screen.

[0007] In order to achieve the above-mentioned purpose, the utility model proposes a high-reliability directional sound screen, comprising:

[0008] A vibration layer, the vibration layer comprising a vibration base material layer and a first conductive layer, wherein the first conductive layer is entirely formed on a surface of the vibration base material layer close to the non-vibration layer;

[0009] A non-vibration layer, which is in contact with the frame of the vibration layer, and includes a non-vibration substrate layer and a second conductive layer, wherein the second conductive layer is entirely formed on a surface of the non-vibration substrate layer close to the vibration layer;

[0010] A pattern layer, wherein the pattern layer is located between the first conductive layer and the second conductive layer, and after the vibration layer and the non-vibration layer frame are attached, an air gap required for the vibration layer to vibrate up and down and generate sound is formed between the pattern layer and the non-vibration layer, and the pattern layer is a plurality of insulating units arranged at intervals;

[0011] An insulating layer, wherein the insulating layer is located between the pattern layer and the first conductive layer or between the pattern layer and the second conductive layer, and the insulating layer includes an antistatic layer.

[0012] In a preferred embodiment, the antistatic layer is a polytetrafluoroethylene layer, and the polytetrafluoroethylene layer is sandwiched between the vibration layer and the non-vibration layer.

[0013] In a preferred embodiment, the thickness of the antistatic layer is 5 um to 20 um.

[0014] In a preferred embodiment, the pattern layer is formed on a surface of the first conductive layer close to the non-vibration layer, and the polytetrafluoroethylene layer is sandwiched between the pattern layer and the second conductive layer.

[0015] In a preferred embodiment, each of the insulating units includes a plurality of insulating protrusions arranged in a square and the sides of the square are parallel to the sides of the corresponding non-vibration substrate layer or the sides of the vibration substrate layer, and the plurality of insulating units are arranged in an array to form a plurality of array units.

[0016] In a preferred embodiment, a supporting point is set at the center of each of the array units, and the supporting point is a single point or a multi-point structure, and the height of the supporting point is less than the height of the insulating bump; or the conductive layer corresponding to the center of each of the array units is removed to form a portion without a conductive layer.

[0017] In a preferred embodiment, the height of the supporting points is 2um to 4um, the height of the insulating bumps is 7um to 12um, and the distance between two adjacent array units is 2.2um to 2.8um.

[0018] In a preferred embodiment, the pattern layer and the insulating layer are fixed via an adhesive layer, and the adhesive layer is a structure of a plurality of adhesive units arranged at intervals corresponding to the structure of the pattern layer or is in the form of a whole surface.

[0019] In a preferred embodiment, a waterproof layer is further provided on the outermost surface of the vibration layer away from the non-vibration layer, and the thickness of the waterproof layer is 1 um to 10 um.

[0020] In a preferred embodiment, a first edge trace is disposed on at least one edge of a surface of the first conductive layer close to the non-vibration layer, and a second edge trace is disposed on at least one edge of a surface of the second conductive layer close to the vibration layer.

[0021] Compared with the prior art, the utility model has the following beneficial effects:

[0022] 1. The utility model replaces the existing ink insulating dielectric layer of the directional sound-emitting screen with an antistatic layer with stable performance, so that it is not easy to lose charge, and the accumulation of static electricity on its surface can be reduced, thereby greatly reducing the influence of the charge generated by air ionization on the air partial pressure, thereby improving the reliability and sound pressure of the directional sound-emitting screen.

[0023] 2. The utility model readjusts the pattern arrangement and spacing of the pattern layer, which can facilitate the printing of the pattern layer on the one hand, and increase the bonding area between the pattern layer and the vibration layer or the non-vibration layer on the other hand, so that the vibration layer and the non-vibration layer are fixed and stable, and the tension on the vibration layer is evenly diffused, which is beneficial to improving the reliability of the formed directional sound screen.

[0024] 3. The utility model sets a support point or a non-conductive layer portion at the center of each array unit of the pattern layer, which can suppress the increase of distortion caused by the collision between the vibration layer and the non-vibration layer at the maximum amplitude of each array unit and thus the reliability failure problem. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic diagram of the structure of a directional sound-emitting screen in a specific embodiment of the utility model;

[0026] Figure 2 It is a schematic diagram of the arrangement structure of the pattern layer in a specific embodiment of the utility model.

[0027] The accompanying drawings are marked as follows:

[0028] 1. Vibration layer, 11. Vibration substrate layer, 12. First conductive layer, 13. First edge routing, 2. Non-vibration layer, 21. Non-vibration substrate layer, 22. Second conductive layer, 23. Second edge routing, 3. Pattern layer, 31. Insulation unit, 32. Insulation bump, 33. Array unit, 34. Support point, 4. Insulation layer, 5. Waterproof layer, 6. Adhesive layer. DETAILED DESCRIPTION

[0029] The specific implementation modes of the present invention are described in detail below, but it should be understood that the protection scope of the present invention is not limited by the specific implementation modes.

[0030] Unless explicitly stated otherwise, throughout the specification and claims, the term “comprise” or variations such as “include” or “comprising”, etc., will be understood to include the stated elements or components but not to exclude other elements or components.

[0031] like Figure 1As shown, the utility model discloses a high-reliability directional sound screen, comprising a vibration layer 1, a non-vibration layer 2, a pattern layer 3 and an insulation layer 4, wherein the frames of the vibration layer 1 and the non-vibration layer 2 are bonded. The utility model replaces the existing ink insulation medium layer of the directional sound screen with an antistatic layer with stable performance, so that it is not easy to lose charge, and the accumulation of static electricity on its surface can be reduced, thereby greatly reducing the influence of the charge generated by air ionization on the air partial pressure, thereby improving the reliability and sound pressure of the directional sound screen.

[0032] The vibration layer 1 serves as an acoustic vibration layer, which specifically includes a vibration substrate layer 11 and a first conductive layer 12. In this embodiment, the vibration substrate layer 11 here can be implemented by a flexible film, such as a PET film. The first conductive layer 12 is formed on the surface of the vibration substrate layer 11 close to the non-vibration layer 2. When implemented, the first conductive layer 12 can be implemented by high-transmittance materials such as nanosilver, indium tin oxide, metalmesh, carbon nanotubes or graphene, or can be a non-transparent conductive material: such as copper or copper-doped oxide or silver or gold. The lower its square resistance, the higher the overall sound efficiency of the directional sound screen, and the square resistance is preferably selected to be less than 10 ohms. In addition, in order to further improve the conductivity of the first conductive layer 12, a first edge wiring 13 can be added at at least one edge of the surface of the first conductive layer 12 close to the non-vibration layer 2. When implemented, the first edge wiring 13 is also implemented by copper or copper-doped oxide or silver or gold.

[0033] The non-vibration layer 2 serves as a non-vibration substrate layer, which specifically includes a non-vibration base material layer 21 and a second conductive layer 22, wherein the second conductive layer 22 is entirely formed on the surface of the non-vibration base material layer 21 close to the vibration layer 1. Preferably, in order to improve the conductivity of the second conductive layer 22, a second edge wiring 23 may be added at least at one edge of the surface of the second conductive layer 22 close to the vibration layer 1. Similarly, during implementation, the second edge wiring 23 is also implemented using copper or copper-doped oxide or silver or gold.

[0034] In this embodiment, the pattern layer 3 is located between the first conductive layer 12 and the second conductive layer 22. After the vibration layer 1 and the non-vibration layer 2 are attached to each other, an air gap (not shown) is formed between the pattern layer 3 and the non-vibration layer 2 for the vibration layer 1 to vibrate up and down and make sounds. In implementation, the pattern layer 3 can be formed on the surface of the first conductive layer 12 close to the non-vibration layer 2, or on the surface of the second conductive layer 22 close to the vibration layer 1. The pattern layer 3 is specifically a plurality of insulating units 31 arranged at intervals.

[0035] In this embodiment, each insulating unit 31 specifically includes a plurality of insulating protrusions 32 arranged in a square and the sides of the square are parallel to the sides of the corresponding non-vibration substrate layer 21 or the sides of the vibration substrate layer 11, and the plurality of insulating units 31 are arranged in an array and arranged to form a plurality of array units 33. The utility model readjusts the pattern arrangement of the pattern layer 3 to be parallel to the sides of the vibration substrate layer 11 or the sides of the non-vibration substrate layer 21, which can facilitate the printing of the pattern layer 3 on the one hand, and can also make the tension on the vibration layer 1 evenly diffused on the other hand, which is conducive to improving the reliability of the formed directional sound screen.

[0036] In addition, more preferably, the utility model sets a support point 34 at the center of each array unit 33, and the support point 34 can be a single point or a multi-point structure, and the height of the support point 34 is less than the height of the insulating bump 32. In a specific embodiment, the height of the support point 34 is 2um to 4um, the height of the insulating bump 32 is 7um to 12um, and the spacing between two adjacent array units 33 (the spacing here is the distance between the centers of two adjacent array units 33) is 2.2um to 2.8um, and in a specific embodiment, the nozzle used in the printing process of the pattern layer 3 is: Konica 1024, the nozzle width is 72mm, and the nozzle is 27um in diameter. Figure 2As shown, the spacing L1 between two adjacent insulating units 31 in the horizontal direction is 3.4931mm, the longitudinal height L2 of each insulating unit 31 is 141um, and the distance L3 from the center of the support point 34 to the center of the insulating unit 31 adjacent thereto is 2.47mm, which can ensure that the bonding area of ​​each insulating unit 31 is maximized. Alternatively, during implementation, the conductive layer corresponding to the center of each array unit 33 (the conductive layer here refers to the first conductive layer 12 and / or the second conductive layer 22) is removed (during implementation, etching or laser light process can be used to achieve this) to form a portion without a conductive layer (not shown in the figure). During implementation, the portion without a conductive layer can be a single solid circle or a hollow ring, and the portion without a conductive layer can be a single point or a single cluster of multiple points. Because, in the reliability failure model, a high probability failure model is: the film material corresponding to the maximum amplitude has the largest deformation due to long-term vibration. As the working time increases, the film material at this position will contact and collide with the non-vibration layer 2 at the earliest time. The collision will cause noise, higher distortion, and reliability failure. In addition, if the diaphragm completely touches the substrate, the depression at the contact point will also cause visual difference, and the overall diaphragm will show regular or flaky collapse. The utility model can avoid the collapse phenomenon by setting a support point 34 at the center of each array unit 33 of the pattern layer 3, and can suppress the increase in distortion caused by the collision between the vibration layer 1 and the non-vibration layer 2 at the maximum amplitude of each array unit 33, thereby causing reliability failure problems. After the non-conductive layer portion is set, the vibration layer 1 corresponding to this portion will not be affected by the electric field force and will be reduced, which can prevent the occurrence of the sound touch failure phenomenon at this portion between the vibration layer 1 and the non-vibration layer 2.

[0037] In addition, the pattern layer 3 and the first conductive layer 12 or the second conductive layer 22 are preferably fixed by an adhesive layer 6. When implemented, the adhesive layer 6 can be a plurality of adhesive unit structures arranged at intervals corresponding to the structure of the pattern layer 3 or a whole surface. In a specific embodiment, the pattern layer 3 and the first conductive layer 12 or the second conductive layer 22 are fixed by adhesive points. Specifically, an adhesive point can be set on each insulating bump 32 on the pattern layer 3, that is, each adhesive point corresponds to an insulating bump 32. The smaller the height of the adhesive point, the better, preferably 1um to 2um. The utility model fixes the pattern layer 3 with the first conductive layer 12 or the second conductive layer 22, so that after the non-vibration layer 2 and the vibration layer 1 are attached, stable vibration units can be formed. In this way, the vibration layer 1 will not be separated from the non-vibration layer 2 when vibrating up and down, thereby eliminating the invalid vibration distance of the vibration layer 1, which can not only reduce the sound distortion of the entire directional sound screen (in a specific implementation case, the design of the bonding point can effectively reduce the total harmonic distortion THD of 1KHz from 20% to less than 5%), but also reduce the driving power of the entire product and improve reliability. During implementation, the bonding point can be formed by a printing process or a dispensing process, and the printing process includes high-precision 3D printing or non-3D printing. In other alternative embodiments, the pattern layer 3 and the first conductive layer 12 or the second conductive layer 22 can also be fixed by a full-surface bonding layer (not shown).

[0038] The insulating layer 4 is formed entirely between the pattern layer 3 and the first conductive layer 12 or between the pattern layer 3 and the second conductive layer 22, and is used to insulate and separate the first conductive layer 12 from the second conductive layer 22 after the vibration layer 1 and the non-vibration layer 2 are frame-bonded. Preferably, during implementation, unlike the ink layer currently used, the utility model replaces the existing ink layer with an antistatic layer with stable performance, so that it is not easy to lose charge, and the accumulation of static electricity on its surface can be reduced, thereby greatly reducing the influence of the charge generated by air ionization on the air partial pressure, thereby improving the reliability and sound pressure of the directional sound screen.

[0039] In specific implementation, the antistatic layer can be a polytetrafluoroethylene layer (i.e., PTFE layer). In a specific embodiment, the polytetrafluoroethylene layer is sandwiched between the vibration layer 1 and the non-vibration layer 2, preferably directly sandwiched between the pattern layer 3 and the second conductive layer 22 or between the first conductive layer 12 and the pattern layer 3. And in implementation, the thickness of the antistatic layer is preferably 5um to 20um, such as a 10um PTFE layer. When processing the PTFE layer, the PTFE can be firstly formed into blocks by extrusion calendering, and then the PTFE film layer can be formed by cutting. In other alternative embodiments, an antistatic layer can also be added to the existing insulating layer (such as a polyurethane acrylic resin ink layer, not shown).

[0040] In addition, preferably, a waterproof layer 5 is also provided on the outermost surface of the vibration layer 1 away from the non-vibration layer 2, which can prevent the vibration layer 1 from absorbing water and softening in a high temperature and high humidity environment, resulting in a smaller distance between the vibration layer electrode and the non-vibration layer electrode, an increase in the electric field strength, and thus an increase in polarization. In implementation, the thickness of the waterproof layer 5 can be 1um to 10um.

[0041] In a specific embodiment, the thickness of the waterproof layer 5 is 1um to 10um, the thickness of the vibration substrate layer 11 is 100um to 125um, the height of the insulating bumps 32 of the pattern layer 3 is 8um to 11um, the spacing between the array units 33 of the pattern layer 3 is 2.2mm to 2.8mm, the thickness of the adhesive layer is 1um to 2um, and the thickness of the antistatic layer is 5um to 20um. And the sound pressure level of this embodiment at a frequency of 1KHz can reach 68 to 71db under a DC voltage of 300V to 350V and an AC voltage of 200V to 250V, and under the conditions of a temperature of 40° and a humidity of 90% in a reliability test box, the sound pressure can remain unchanged for 72H, and the impedance analyzer analyzes that the resistance R value remains consistent under ±300 to 350V DC.

[0042] The advantages of the present invention are as follows: 1. The present invention replaces the existing ink insulating dielectric layer of the directional sound screen with an antistatic layer with stable performance, so that it is not easy to lose charge, and the accumulation of static electricity on its surface can be reduced, thereby greatly reducing the influence of the charge generated by air ionization on the air partial pressure, and thus improving the reliability and sound pressure of the directional sound screen. 2. The present invention readjusts the pattern arrangement and spacing of the pattern layer, which can facilitate the printing of the pattern layer on the one hand, and increase the bonding area between the pattern layer and the vibration layer or the non-vibration layer on the other hand, so that the vibration layer and the non-vibration layer are fixed and stable, and the tension on the vibration layer can be evenly diffused, which is beneficial to improving the reliability of the formed directional sound screen. 3. The present invention sets a support point or a non-conductive layer portion at the center of each array unit of the pattern layer, which can suppress the increase in distortion caused by the collision between the vibration layer and the non-vibration layer at the maximum amplitude of each array unit, and thus suppress the reliability failure problem caused by the increase in distortion.

[0043] The foregoing description of specific exemplary embodiments of the utility model is for the purpose of illustration and illustration. These descriptions are not intended to limit the utility model to the precise form disclosed, and it is clear that many changes and variations can be made based on the above teachings. The purpose of selecting and describing the exemplary embodiments is to explain the specific principles of the utility model and its practical application, so that those skilled in the art can realize and utilize various different exemplary embodiments of the utility model and various different options and changes. The scope of the utility model is intended to be defined by the claims and their equivalents.

[0044] The foregoing description of specific exemplary embodiments of the utility model is for the purpose of illustration and illustration. These descriptions are not intended to limit the utility model to the precise form disclosed, and it is clear that many changes and variations can be made based on the above teachings. The purpose of selecting and describing the exemplary embodiments is to explain the specific principles of the utility model and its practical application, so that those skilled in the art can realize and utilize various different exemplary embodiments of the utility model and various different options and changes. The scope of the utility model is intended to be defined by the claims and their equivalents.

Claims

1. A high-reliability directional sound screen, characterized in that: The directional sound screen comprises: A vibration layer, the vibration layer comprising a vibration base material layer and a first conductive layer, wherein the first conductive layer is entirely formed on a surface of the vibration base material layer close to the non-vibration layer; A non-vibration layer is attached to the frame of the vibration layer, the non-vibration layer comprises a non-vibration substrate layer and a second conductive layer, the second conductive layer is entirely formed on a surface of the non-vibration substrate layer close to the vibration layer; A pattern layer, wherein the pattern layer is located between the first conductive layer and the second conductive layer, and after the vibration layer and the non-vibration layer frame are attached, an air gap required for the vibration layer to vibrate up and down and generate sound is formed between the pattern layer and the non-vibration layer, and the pattern layer is a plurality of insulating units arranged at intervals; An insulating layer, wherein the insulating layer is located between the pattern layer and the first conductive layer or between the pattern layer and the second conductive layer, and the insulating layer includes an antistatic layer.

2. A high-reliability directional sound screen as claimed in claim 1, characterized in that: The antistatic layer is a polytetrafluoroethylene layer, and the polytetrafluoroethylene layer is sandwiched between the vibration layer and the non-vibration layer.

3. A high-reliability directional sound screen as claimed in claim 1 or 2, characterized in that: The thickness of the antistatic layer is 5um to 20um.

4. A high-reliability directional sound screen as claimed in claim 2, characterized in that: The pattern layer is formed on a surface of the first conductive layer close to the non-vibration layer, and the polytetrafluoroethylene layer is sandwiched between the pattern layer and the second conductive layer.

5. A high-reliability directional sound screen as claimed in claim 1, characterized in that: Each of the insulating units includes a plurality of insulating protrusions arranged in a square shape and the sides of the square shape are parallel to the sides of the corresponding non-vibration substrate layer or the sides of the vibration substrate layer. The plurality of insulating units are arranged in an array and form a plurality of array units.

6. A high-reliability directional sound screen as claimed in claim 5, characterized in that: A supporting point is set at the center of each array unit, and the supporting point is a single point or a multi-point structure, and the height of the supporting point is less than the height of the insulating bump; or the conductive layer corresponding to the center of each array unit is removed to form a conductive layer-free portion.

7. A high-reliability directional sound screen as claimed in claim 6, characterized in that: The height of the supporting point is 2um-4um, the height of the insulating bump is 7um-12um, and the distance between two adjacent array units is 2.2um-2.8um.

8. A high-reliability directional sound screen as claimed in claim 1 or 5, characterized in that: The pattern layer and the insulating layer are fixed via an adhesive layer, and the adhesive layer is a plurality of adhesive unit structures arranged at intervals corresponding to the structure of the pattern layer or is in a whole surface shape.

9. A high-reliability directional sound screen as claimed in claim 1, characterized in that: A waterproof layer is also arranged on the outermost surface of the vibration layer away from the non-vibration layer, and the thickness of the waterproof layer is 1 um to 10 um.

10. A high-reliability directional sound screen as claimed in claim 1, characterized in that: A first edge wiring is disposed on at least one edge of a surface of the first conductive layer close to the non-vibration layer, and a second edge wiring is disposed on at least one edge of a surface of the second conductive layer close to the vibration layer.

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