A planar ultra-thin micro-acoustic-electric transducer and a Bluetooth headset

Abstract

The present invention discloses a planar ultra-thin miniature acoustic-electric transducer device and a Bluetooth headset, and relates to the technical field of acoustic-electric conversion equipment. The planar ultra-thin miniature acoustic-electric transducer device comprises: a thin film substrate, a first planar conductive coil located on the first surface of the thin film substrate, and a second planar conductive coil located on the second surface; the inner edge ends of the first planar conductive coil and the second planar conductive coil are vertically opposite to each other in the thickness direction of the thin film substrate, and are connected through a first via hole on the thin film substrate, and together constitute a voice coil attached to the thin film substrate, and the outer edge ends of the first planar conductive coil and the second planar conductive coil lead out the first terminal and the second terminal of the voice coil respectively. The present invention designs the voice coil as a front and back structure of the diaphragm, reduces the size and area of ​​the voice coil by superposition, and greatly reduces the horizontal area occupied by the single-sided voice coil, which is conducive to the miniaturization demand of the acoustic-electric transducer device.

Description

Technical Field

[0001] The present invention relates to the technical field of acoustic-electric conversion equipment, and in particular to a planar ultra-thin miniature acoustic-electric transducer device and a Bluetooth headset. Background Art

[0002] Traditional speakers are made of a magnetic ring, an iron core, a paper cone with a voice coil, and a frame. The voice coil is made by winding enameled wire around a paper tube connected to the paper cone. The voice coil is in the gap between the magnetic ring and the iron core. When the audio current signal passes through the voice coil, the voice coil generates an alternating magnetic field. Under the action of the magnetic field of the magnetic ring, the voice coil drives the paper cone to vibrate and produce sound. In order to achieve the required sound and power effects, this type of speaker is large in size and is difficult to meet the requirements of some small electronic devices such as mobile phones. In addition, the materials used are very complicated in the production process. Summary of the invention

[0003] In view of this, one of the purposes of the present invention is to overcome the defect that traditional acoustic-electric transducer devices cannot meet the current miniaturization demand, and to provide a planar ultra-thin miniature acoustic-electric transducer device.

[0004] In order to achieve the above object, the solution of the present invention is:

[0005] A planar ultra-thin micro-acoustic-electric transducer device, comprising:

[0006] A film substrate having a first via hole;

[0007] A first planar conductive coil located on a first surface of the film substrate;

[0008] A second planar conductive coil located on a second surface of the film substrate;

[0009] The inner edge ends of the first planar conductive coil and the second planar conductive coil are vertically opposite to each other in the thickness direction of the film substrate, and are connected through a first via hole on the film substrate to jointly constitute a voice coil attached to the film substrate, and the outer edge ends of the first planar conductive coil and the second planar conductive coil respectively lead out a first terminal and a second terminal of the voice coil.

[0010] Furthermore, the planar ultra-thin micro-acoustic-electric transducer device also includes an annular frame attached to the first surface and / or the second surface of the film substrate, and the annular frame is located around the voice coil; the portion of the film substrate between the voice coil and the annular frame is a hollow structure and is covered by an adhesive film; the film substrate located between the annular frames and the adhesive film together constitute a diaphragm.

[0011] Furthermore, the annular frame includes: a first planar bending structure located on the first surface of the film substrate, and a second planar bending structure located on the second surface of the film substrate; wherein the first planar bending structure and the second planar bending structure do not overlap at least partially in the thickness direction of the film substrate.

[0012] Furthermore, the planar ultra-thin micro-acoustic-electric transducer device also includes: a first conductive connection structure located on the first surface of the film substrate, and a second conductive connection structure located on the second surface of the film substrate; the first planar conductive coil located on the film substrate is sequentially led out to the first terminal through the first conductive connection structure and the first planar bending structure; the second planar conductive coil located on the film substrate is sequentially led out to the second terminal through the second conductive connection structure and the second planar bending structure, and the first planar bending structure and the second planar bending structure are conductors.

[0013] Furthermore, the annular frame further includes: a third planar bending structure that is not connected to the first planar bending structure and the second planar bending structure, and the third planar bending structure is located on the first surface or the second surface of the film substrate.

[0014] Furthermore, the planar ultra-thin micro-acoustic-electric transducer device further includes: a first covering film disposed on one side of the first surface of the film substrate, the covering film being a window structure at least in the area relative to the area within the annular frame and the area of ​​the first terminal.

[0015] Furthermore, the planar ultra-thin micro-acoustic-electric transducer device further includes: a second covering film disposed on one side of the second surface of the film substrate, the covering film being a window structure at least in the area relative to the annular frame and the area of ​​the second terminal.

[0016] Furthermore, a metal plating layer is formed on the surface of the voice coil.

[0017] Another object of the present invention is to overcome the deficiencies of the prior art and provide a Bluetooth headset having the planar ultra-thin micro-acoustic-electric transducer device.

[0018] After adopting the above scheme, compared with the prior art, the present invention has the following advantages:

[0019] The planar ultra-thin miniature acoustic-electric transducer device and Bluetooth headset of the present invention designs the voice coil as a front and back structure of the diaphragm, and reduces its size and area by half by superimposing it, thereby greatly reducing the size and area of ​​the single plane occupied by the single-sided voice coil, which is beneficial to the miniaturization demand of the acoustic-electric transducer device. In addition, the acoustic-electric transducer device in the embodiment of the present invention has a simple structure and is easy to implement and process. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 Schematic diagram of the layer structure of a planar ultra-thin micro-acoustic-electric transducer device in an embodiment of the present invention;

[0021] Figure 2a is a front view of a structural example 1 of a planar ultra-thin micro-acoustic-electric transducer device in an embodiment of the present invention;

[0022] Figure 2b is a front perspective view of a first structural example of a planar ultra-thin micro-acoustic-electric transducer device in an embodiment of the present invention;

[0023] Figure 3 This is a second structural example of a planar ultra-thin micro-acoustic-electric transducer device in an embodiment of the present invention;

[0024] Figure 4 This is a structural example 3 of the planar ultra-thin micro-acoustic-electric transducer device in the embodiment of the present invention;

[0025] Figure 5 This is a fourth structural example of a planar ultra-thin micro-acoustic-electric transducer device in an embodiment of the present invention;

[0026] Figure 6 This is a structural example 5 of the planar ultra-thin micro-acoustic-electric transducer device in the embodiment of the present invention;

[0027] Figure 7 This is the sixth structural example of the planar ultra-thin micro-acoustic-electric transducer device in the embodiment of the present invention. DETAILED DESCRIPTION

[0028] The following description and the accompanying drawings fully illustrate specific embodiments of the present invention so that those skilled in the art can practice them. Other embodiments may include structural, logical, electrical, process and other changes. The examples represent possible variations only. Unless explicitly required, separate components and functions are optional, and the order of operation may vary. Parts and features of some embodiments may be included in or replace parts and features of other embodiments. The scope of the embodiments of the present invention includes the entire scope of the claims, and all available equivalents of the claims. In this article, these embodiments of the present invention may be represented individually or collectively by the term "invention", which is merely for convenience, and if more than one invention is disclosed in fact, it is not intended to automatically limit the scope of the application to any single invention or inventive concept.

[0029] It should be noted that the various technical features in the embodiments of the present invention can be combined with each other without conflict.

[0030] The embodiment of the present invention discloses a planar ultra-thin micro-acoustic-electric transducer device, specifically, as shown in FIG. Figure 2a and Figure 2b As shown, Figure 1 Schematic diagram of the layer structure of a planar ultra-thin micro-acoustic-electric transducer device in an embodiment of the present invention; Figure 2a is a front view of a planar ultra-thin micro-acoustic-electric transducer device in an embodiment of the present invention; Figure 2b : is a front perspective view of a planar ultra-thin micro-acoustic-electric transducer device in an embodiment of the present invention. The planar ultra-thin micro-acoustic-electric transducer device comprises: a thin film substrate 100, a first planar conductive coil 210 and a second planar conductive coil 220; wherein the first planar conductive coil 210 is located on the first surface 101 of the thin film substrate 100; and the second planar conductive coil 220 is located on the second surface 102 of the thin film substrate 100. The first planar conductive coil 210 and the second planar conductive coil 220 are coiled spiral coil structures, and their shapes are not limited to polygonal ring structures such as circular rings and rectangular rings. A rectangular ring structure is used in this example. The first planar conductive coil 210 and the second planar conductive coil 220 respectively have an inner edge end (i.e., an inner line end) and an outer edge end (i.e., an outer line end) located inside, wherein the inner edge ends of the two planar conductive coils are vertically opposite to each other in the thickness direction of the film substrate 100, and are connected through the first via 110 on the film substrate 100, so that the planar conductive coils located on both sides of the film substrate 100 together constitute a voice coil 200 attached to the film substrate 100 (as a diaphragm), and the outer edge ends of the first planar conductive coil 210 and the second planar conductive coil 220 respectively lead out the first wiring terminal 211 and the second wiring terminal 221 of the voice coil 200. The first wiring terminal 211 and the second wiring terminal 221 are used to connect the driving circuit of the voice coil.

[0031] The first via 110 on the film substrate in this embodiment that realizes the interconnection between the first planar conductive coil 210 and the second planar conductive coil 220 is not limited to being formed by metallized vias, conductive columns, pins, etc.

[0032] In this embodiment, the first terminal 211 and the second terminal 221 of the voice coil 200 are not limited to being led out by a wire, an FPC connector, or the like.

[0033] In the embodiment of the present invention, the voice coil is designed as a structure of the front and back sides of the diaphragm, and its size and area are halved by superposition, which greatly reduces the size and area of ​​the single-sided voice coil on a single plane, which is beneficial to the miniaturization demand of the acoustic-electric transducer device. In addition, the acoustic-electric transducer device in the embodiment of the present invention has a simple structure and is easy to process.

[0034] like Figures 3 to 5As shown, in some optional embodiments, the planar ultra-thin micro-acoustic-electric transducer device in the embodiment of the present invention may further include: an annular frame 300, which corresponds to the shape of the voice coil 200 and surrounds the voice coil 200 to fix the diaphragm, prevent the diaphragm from wrinkling, and enhance the overall strength. The material of the annular frame is not limited to conductive materials or insulating materials. In some embodiments, an annular frame on the market can be directly selected, such as a fixing ring on the upper and lower sides.

[0035] In some embodiments, the annular frame can be completely formed on one side of the film substrate 100 (i.e., the first surface 101 or the second surface 102), for example, on the same side as the first planar conductive coil 210, or on the same side as the second planar conductive coil 220. In some other embodiments, the components of the annular frame can also be located on both sides of the film substrate 100 (i.e., part of the frame is located on the first surface 101, and the other part of the frame is located on the second surface 102), and the front and back sides together constitute the annular frame. Compared with the annular frame formed on one side, this solution can provide a more stable structural strength because it is located on both sides of the film substrate 100. Among them, Figure 4-5 The medium and light colors are the perspective structure of the other side.

[0036] Specifically, the annular frame 300 in the embodiment of the present invention may include: a first planar bending structure 310 located on the first surface 101 of the film substrate 100, and a second planar bending structure 320 located on the second surface 102 of the film substrate 100. The first planar bending structure 310 and the second planar bending structure 320 together form an annular frame 300 surrounding the voice coil 200 and corresponding to the shape of the voice coil 200. The first planar bending structure 310 and the second planar bending structure 320 may be the target shapes of the annular frame 300, respectively. In other embodiments, they may also constitute different structural segments of the annular frame 300, and are combined to form the annular frame 300.

[0037] The annular frame 300 in this embodiment is shown to be composed of two different structural segments. In other embodiments, it can also be composed of three, four or more structural segments, which is not limited here.

[0038] Specifically, in some optional embodiments, the annular frame 300 further includes: a third planar bending structure 330 connected / not connected to the first planar bending structure 310 and the second planar bending structure 320 , located on the first surface 101 or the second surface 102 of the film substrate 100 .

[0039] Furthermore, the different structural segments constituting the annular frame 300 may not overlap at all in the thickness direction of the film substrate, or may overlap partially in the thickness direction of the film substrate. Relatively speaking, by forming the annular frame 300 by forming non-overlapping / slightly overlapping structural segments on both sides of the film substrate 100, it is beneficial to reduce the overall weight of the device and improve the sensitivity of the diaphragm.

[0040] like Figure 6 As shown, in some embodiments, the annular frame 300 in the embodiment of the present invention can be formed by the lead-out lines of the first terminal 211 and the second terminal 221 of the voice coil 200. Specifically, the first planar bending structure 310 and the second planar bending structure 320 are conductor structures. The planar ultra-thin micro-acoustic-electric transducer device may also include: a first conductive connection structure 410 located on the first surface 101 of the film substrate 100, and a second conductive connection structure 420 located on the second surface 102 of the film substrate 100. Among them, the first planar conductive coil 210 located on the film substrate 100 leads out the first terminal 211 in turn through the first conductive connection structure 410 and the first planar bending structure 310; the second planar conductive coil 220 located on the film substrate 100 leads out the second terminal 221 in turn through the second conductive connection structure 420 and the second planar bending structure 320. In this embodiment, the first planar bending structure 310 and the second planar bending structure 320 are used to form the annular frame 300 and cooperate with the first planar conductive coil 210 and the second planar conductive coil 220 to lead out the first terminal 211 and the second terminal 221 of the voice coil 200 respectively.

[0041] In the above-mentioned embodiment, the first planar conductive coil 210, the first conductive connection structure 410, the first planar bending structure 310 and the first terminal 211 located on the first surface 101 of the film substrate 100 can be formed by copper foil; the second planar conductive coil 220, the second conductive connection structure 420, the second planar bending structure 320 and the second terminal 221 located on the second surface 102 of the film substrate 100 can also be formed by copper foil.

[0042] In some embodiments, other planar bending structures (such as the third planar bending structure 330 ) can also be simultaneously manufactured using the copper foil on the same side.

[0043] In some embodiments, the first terminal 211 and the second terminal 221 of the voice coil 200 in the embodiment of the present invention are led out on the same side of the film substrate 100, and a corresponding second via 130 can be provided on the film substrate 100 so that the first terminal 211 and the second terminal 221 are located on the same surface of the substrate to facilitate subsequent circuit connection.

[0044] In some other solutions, a third via hole 140 may also be provided, and the first terminal 211 and the second terminal 221 form contact surfaces on two sides of the film substrate 100 respectively.

[0045] The first via hole 110 , the second via hole 130 , and the third via hole 140 in the embodiment of the present invention can be made conductive by pre-drilling holes on the surface of the film substrate and then using the via metallization technology in the prior art.

[0046] The film substrate 100 in the embodiment of the present invention can be selected from PI (polyimide film), PET, PEN and other film substrates. The above substrates are more suitable as diaphragm materials due to their good strength and flexibility.

[0047] like Figure 7 As shown, in some embodiments, the portion of the film substrate 100 of the planar ultra-thin micro-acoustic-electric transducer device between the voice coil and the annular frame 300 is a hollow structure 120, and is covered by an adhesive film 130; the film substrate 100 located within the annular frame 300 and the adhesive film 130 together constitute a diaphragm.

[0048] Although PI, PET, PEN and other materials are used as the diaphragm in the embodiment of the present invention, the sensitivity is still low. The adhesive film 130 is compounded at the hollow 120 of the film substrate in the above manner, so that the adhesive film 130 and the remaining film substrate 100 together form the diaphragm, and the sensitivity of the diaphragm is improved by the adhesive film 130. Among them, the adhesive film 130 can be selected from silicone adhesive films or other adhesive films on the market.

[0049] In some embodiments, the hollow 120 may be located in an area of ​​the film substrate 100 between the voice coil and the annular frame 300, where the first conductive connection structure 410 and the second conductive connection structure 420 are not located. In this embodiment, by retaining the first conductive connection structure 410 and the second conductive connection structure 420 and the film substrate 100 at the corresponding position, on the one hand, the first conductive connection structure 410 and the second conductive connection structure 420 will not be affected. On the other hand, the film substrate at the voice coil 200 and the film substrate at the annular frame 300 are still connected through the first conductive connection structure 410 and the second conductive connection structure 420, thereby ensuring the structural stability and tension of the film substrate and the subsequent adhesive film, thereby ensuring the sensitivity and reliability of the diaphragm.

[0050] Preferably, the line width of the first conductive connection structure 410 / the second conductive connection structure is smaller than that of the first planar bending structure 310 / the second planar bending structure 320 .

[0051] Preferably, the path of the first conductive connection structure 410 connecting the first planar conductive coil 210 and the first planar bending structure 310 is not a minimum path, so as to ensure that the connection structure provides a stronger structural strength for the diaphragm. The same is true for the second conductive connection structure 420.

[0052] In some optional embodiments, the present invention further comprises: a first covering film disposed on one side of the first surface 101 of the film substrate 100 , wherein the covering film has a window structure at least in the area relative to the inner region of the annular frame 300 and the area of ​​the first terminal 211 .

[0053] In some optional embodiments, the present invention further comprises: a second covering film disposed on one side of the second surface 102 of the film substrate 100 , wherein the covering film has a window structure at least in the area relative to the inside of the annular frame 300 and the area of ​​the second terminal 221 .

[0054] In some optional embodiments, a metal coating may be formed on the surface of one or more of the first planar conductive coil, the second planar conductive coil, the first conductive connection structure, the second conductive connection structure, the first planar bending structure, the second planar bending structure, the third planar bending structure, the first terminal, and the second terminal in the embodiments of the present invention. The metal coating may be used to enhance the strength of the circuit itself, the weldability, and the ability to pass large currents and high-frequency signals.

[0055] The metal plating layer may be copper, aluminum, silver, gold, nickel, etc. Preferably, the metal plating layer may be a multilayer structure, such as a silver-gold layer, a copper-nickel-gold layer, etc.

[0056] The embodiment of the present invention discloses a manufacturing method for a planar ultra-thin micro-acoustic-electric transducer device, comprising:

[0057] Step 1: Open one or more vias at set positions on the film substrate to connect two sides of the film substrate, and metallize the vias;

[0058] Step 2: Forming a first planar conductive coil, a first conductive connection structure, a first planar bending structure, and a first terminal on the first surface of the film substrate using copper foil;

[0059] Step 3, forming a second planar conductive coil, a second conductive connection structure, a second planar bending structure, a third planar bending structure, and a second terminal on the second surface of the film substrate using copper foil;

[0060] Step 4, electroplating or chemical plating the product of step 3 to form a metal coating on the surface of the copper foil;

[0061] Step 5, attaching cover films on the upper and lower parts of the product in step 4 respectively;

[0062] Step 6, processing the area between the annular frame and the voice coil in the product of step 5, which is not the first conductive connection structure and the second conductive connection structure, to form a hollow structure at the corresponding position;

[0063] Step 7: Form a covering film within the annular frame.

[0064] The above method in the embodiment of the present invention has the advantages of simple process and easy implementation, and the planar ultra-thin micro-acoustic-electric transducer device manufactured by the method has the advantages of high sensitivity and high reliability.

[0065] Another object of the present invention is to provide a Bluetooth headset having the planar ultra-thin micro-acoustic-electric transducer device described in any one of the above.

[0066] Those skilled in the art will also appreciate that the various illustrative logic blocks, modules, circuits, and algorithmic steps described in conjunction with the embodiments herein can all be implemented as electronic hardware, computer software, or a combination thereof. In order to clearly illustrate the interchangeability between hardware and software, various illustrative components, blocks, modules, circuits, and steps are generally described above around their functions. Whether such functions are implemented as hardware or software depends on specific applications and the design constraints imposed on the entire system. A skilled person can implement the described functions in an alternative manner for each specific application, but such implementation decisions should not be interpreted as departing from the scope of protection of the present disclosure.

Claims

1. A planar ultra-thin micro-acoustic-electric transducer device, characterized in that: include: A film substrate having a first via hole; A first planar conductive coil located on a first surface of the film substrate; A second planar conductive coil located on a second surface of the film substrate; The inner edge ends of the first planar conductive coil and the second planar conductive coil are vertically opposite to each other in the thickness direction of the film substrate, and are connected through the first via hole on the film substrate to form a voice coil attached to the film substrate, and the outer edge ends of the first planar conductive coil and the second planar conductive coil lead out the first terminal and the second terminal of the voice coil respectively; an annular frame attached to the first surface and / or the second surface of the film substrate and located around the voice coil; The portion of the film substrate between the voice coil and the annular frame is a hollow structure and is covered by an adhesive film; The film substrate located between the annular frames and the adhesive film together form a diaphragm; The method for manufacturing the planar ultra-thin micro-acoustic-electric transducer device comprises the following steps: Step 1: Open one or more vias at set positions on the film substrate to connect two sides of the film substrate, and metallize the vias; Step 2: Forming a first planar conductive coil, a first conductive connection structure, a first planar bending structure, and a first terminal on the first surface of the film substrate using copper foil; Step 3, forming a second planar conductive coil, a second conductive connection structure, a second planar bending structure, a third planar bending structure, and a second terminal on the second surface of the film substrate using copper foil; Step 4, electroplating or chemical plating the product of step 3 to form a metal coating on the surface of the copper foil; Step 5, attaching cover films on the upper and lower parts of the product in step 4 respectively; Step 6, processing the area between the annular frame and the voice coil in the product of step 5, which is not the first conductive connection structure and the second conductive connection structure, to form a hollow structure at the corresponding position; Step 7: Form a covering film within the annular frame.

2. The planar ultra-thin micro-acoustic-electric transducer device according to claim 1, characterized in that: The annular frame includes: a first planar bending structure located on the first surface of the film substrate, and a second planar bending structure located on the second surface of the film substrate; wherein the first planar bending structure and the second planar bending structure do not overlap at least partially in the thickness direction of the film substrate.

3. The planar ultra-thin micro-acoustic-electric transducer device according to claim 2, characterized in that: The first planar bending structure and the second planar bending structure are conductors; further comprising: a first conductive connection structure located on the first surface of the film substrate, and a second conductive connection structure located on the second surface of the film substrate; The first planar conductive coil located on the film substrate leads out the first terminal in sequence through the first conductive connection structure and the first planar bending structure; The second planar conductive coil located on the film substrate leads out the second terminal through the second conductive connection structure and the second planar bending structure in sequence.

4. The planar ultra-thin micro-acoustic-electric transducer device according to claim 2, characterized in that: The annular frame further includes: a third planar bending structure which is not connected to the first planar bending structure and the second planar bending structure and is located on the first surface or the second surface of the film substrate.

5. The planar ultra-thin micro-acoustic-electric transducer device according to claim 1, characterized in that: Also includes: A first covering film is disposed on one side of the first surface of the film substrate, and the covering film has a window structure at least in the area relative to the area within the annular frame and the area of ​​the first terminal.

6. The planar ultra-thin micro-acoustic-electric transducer device according to claim 1, characterized in that: Also includes: A second covering film is disposed on one side of the second surface of the film substrate, and the covering film has a window structure at least in the area relative to the area within the annular frame and the area of ​​the second terminal.

7. The planar ultra-thin micro-acoustic-electric transducer device according to claim 1, characterized in that: A metal plating layer is formed on the surface of the voice coil.

8. A Bluetooth headset, characterized in that: A planar ultra-thin micro-acoustic-electric transducer device according to any one of claims 1 to 7.

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