Optical Component Driving Device, Camera Device, and Electronic Device

Abstract

The present invention provides an optical component driving device, a camera device, and an electronic device each constituted by an insulating material having a strong adhesive strength with an adhesive. The OIS lens driving device (1) includes a base (2), a metal sub-base (3) fixed on the base (2), a metal lower plate (4) fixed on the sub-base (3), an upper plate (6) slidable on the lower plate (4), and four SMA wires (7) whose both ends are fixed to the hook portions (48) of the lower plate (4) and the hook portions (68) of the upper plate (6). The sub-base (3) has three metal sub-base bodies and a polyimide resin layer (30) formed so as to cover the upper surfaces of the three sub-base bodies.

Description

Technical Field

[0001] The present invention relates to an optical component driving device, a camera device, and an electronic device used in an electronic device such as a smartphone. Background Art

[0002] In a camera device equipped with an OIS (Optical Image Stabilizer) function, there is a camera device in which an SMA (Shape Memory Alloy) wire is disposed between a movable member that holds an optical component and a support structure that holds an imaging element, and the movable member and the support structure are relatively moved by contraction of the SMA wire. As a document disclosing a technique related to such a camera device, there is Patent Document 1. The camera device described in Patent Document 1 includes a movable member having a leaf spring plate and a support structure in which a support member and a conductive plate are laminated on a base. The movable member and the support structure are disposed opposite to each other with a bearing interposed therebetween. The leaf spring plate and the conductive plate each have a hook portion at a corner in a cross diagonal direction, and an SMA wire is laid between the hook portion of the leaf spring plate and the hook portion of the conductive plate. When the SMA wire contracts, the movable member slides relative to the support structure on the bearing.

[0003]

Prior Art Documents

[0004]

Patent Documents

[0005]

Patent Document 1

[0006]

Problems to be Solved by the Invention

[0007] However, in the technique of Patent Document 1, an electrically insulating layer for insulating from the conductive plate on the support member is formed of parylene, which is a kind of high molecular compound. However, it cannot be said that the bonding strength of the support member, the adhesive for bonding the conductive plate, and parylene is strong enough.

[0008] The present invention has been made in view of such problems, and an object thereof is to provide an optical component driving device, a camera device, and an electronic device constituted by an insulating material having a strong bonding strength with an adhesive.

[0009]

Means for Solving the Problems

[0010] In order to solve the above problems, an optical component driving device according to a preferred embodiment of the present invention is characterized by including: a sub-base; a metal lower plate fixed to the sub-base; an upper plate sliding on the lower plate; and a plurality of SMA wires whose both ends are fixed to the lower plate and the upper plate, wherein the sub-base has a metal sub-base body and a polyimide resin layer formed so as to cover the upper surface of the sub-base body.

[0011] In this embodiment, it is also possible that the polyimide resin layer is formed by electrodeposition coating.

[0012] A camera device according to another preferred embodiment of the present invention is characterized by including the above optical component driving device.

[0013] A camera device according to another preferred embodiment of the present invention is characterized by including the above camera device.

[0014]

Advantages of the Invention

[0015] In the optical component driving device of the present invention, the metal sub-base body is covered with a polyimide resin layer. Therefore, when the lower plate is adhesively fixed to the sub-base, the polyimide resin layer has insulation properties and strong adhesive strength with the adhesive. Therefore, it is possible to provide an optical component driving device, a camera device, and an electronic device composed of an insulating material having strong adhesive strength with the adhesive. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a front view of a smartphone 99 which is an electronic device equipped with the camera device 10.

[0017] Figure 2 is an exploded Figure 1 is a perspective view of the OIS lens driving device 1.

[0018] Figure 3 is Figure 2 is a perspective view of a laminate of the sub-base 3 and the lower plate 4 of the OIS lens driving device 1.

[0019] Figure 4 is a view showing a plate for a tensile test used for the experiment to confirm the effects of the present invention.

[0020] Figure 5 is a bar graph of the peel strength per unit area of the insulator recorded in the experiment to confirm the effects of the present invention.

[0021] Figure 6 is a photograph of the peel surface of a parylene plate and a SUS304 stainless steel plate used for the experiment to confirm the effects of the present invention.

[0022] Figure 7 This is a photograph of the peeling surface of the PET laminate and the SUS304 stainless steel plate used in the experiment for confirming the effects of the present invention.

[0023] Figure 8 This is a photograph of the peeling surface of the PI spray plate and the SUS304 stainless steel plate used in the experiment for confirming the effects of the present invention. Detailed Embodiments

[0024] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. As Figure 1 shown, the camera device 10 is housed in the housing of the smartphone 99. The camera device 10 includes: a lens unit 11 as an optical component; an image sensor 12 that performs photoelectric conversion on the light incident from the subject via the lens unit 11; an AF (Autofocus) actuator 13 that drives the lens unit 11 in the optical axis direction; and an OIS lens driving device 1 that drives the AF actuator 13 in a plane orthogonal to the optical axis.

[0025] Hereinafter, sometimes the side where the optical axis of the lens unit 11 is located on the side of the subject is referred to as the upper side, and the side provided with the image sensor 12 on the side opposite to the subject is referred to as the lower side.

[0026] As Figure 2 shown, the OIS lens driving device 1 includes: a metal base 2; a metal sub-base 3 fixed on the base 2; a metal lower plate 4 fixed on the sub-base 3; a plurality of sliding members 5 provided on the sub-base 3; an upper plate 6 facing the lower plate 4 and sliding on the sliding members 5; and four SMA wires 7 whose both ends are fixed to a hook portion 48 provided on the lower plate 4 and a hook portion 68 provided on the upper plate 6.

[0027] In the above-described respective parts, the base 2, the sub-base 3, the lower plate 4, and the sliding members 5 form a fixed part, and the upper plate 6 forms a movable part that relatively moves with respect to the fixed part. The constitution of each part is as described below.

[0028] The base 2 has a thin square shape with a through hole 27 at the center. A part of one end edge of the base 2 is slightly cut so that the AF actuator 13 can be externally electrically connected from here.

[0029] The sub-base 3 has a thin square shape with a through hole 37 at the center. The upper surface of the main body of the sub-base 3 is covered with a polyimide resin layer 30 as an insulating material. The entire surface of the main body of the sub-base 3 may also be covered with the polyimide resin layer 30. Sliding member mounting portions 31 are provided at four positions surrounding the through hole 37 of the sub-base 3. The lower surface of the sub-base 3 is adhesively fixed to the upper surface of the base 2.

[0030] The lower plate 4 is composed of six plates 40-j (j = 1 to 6). AsFigure 3 As shown, the lower plate 4 as a whole has a hole shape corresponding to the through hole 37 and a square shape corresponding to the outer shape of the sub-base 3. The lower surface of the lower plate 4 is bonded and fixed to the upper surface of the sub-base 3. Six plates 40-j (j = 1 to 6) are arranged at intervals from each other. The six plates 40-j (j = 1 to 6) are insulated from the three metal sub-base bodies through the polyimide resin layer 30 of the sub-base 3.

[0031] One end of the plates 40-1 to 40-5 among the plates 40-j (j = 1 to 6) extends downward from the end edge of the sub-base 3 to form terminals. In addition, the other ends of the plates 40-2 to 40-5 form hook portions 48. Two hook portions 48 are provided at each of the two angular portions forming a specified diagonal.

[0032] Cuts 45 are provided at positions of the plates 40-3, 40-4, and 40-6 in the lower plate 4 corresponding to the sliding member mounting portion 31, and the sliding member mounting portion 31 is exposed upward through the cuts 45. The lower surface of the sliding member 5 is adhesively fixed to the sliding member mounting portion 31. The lower surface of the sliding member 5 is flat, but a part of the upper surface bulges, and the upper plate 6 abuts against and slides on this part.

[0033] The upper plate 6 has: a substantially square main body portion 60 having a through hole 67 at the center; and two arms 65 extending outward from two opposite end edges along the end edges. Each arm 65 extends around the outside of the chamfered corner portion forming a diagonal from this end edge and further extends along the adjacent end edge. Connecting pieces 61 are respectively mounted at the corner portions of the upper plate 6 forming the other diagonal, and two hook portions 68 are respectively provided at the front ends of the connecting pieces 61. The hook portions 68 can also be directly provided on the upper plate 6.

[0034] The hook portions 68 of the upper plate 6 and the hook portions 48 of the lower plate 4 form the four corners of a square. The upper plate 6 and the lower plate 4 overlap, and the sliding member 5 is sandwiched therebetween. The front ends of the arms 65 are respectively fixed to the plates 40-1 and 40-6 and are electrically connected.

[0035] One end and the other end of the SMA wire 7 are riveted and fixed to the hook portion 68 of the upper plate 6 and the hook portion 48 of the lower plate 4. When current is supplied to the SMA wire 7, the SMA wire 7 contracts due to the heat generated by energization respectively. Due to the contraction of the SMA wire 7, the upper plate 6 of the movable portion slides on the sliding member 5 and moves relative to the fixed portion.

[0036] Here, there are roughly two methods for forming the sub-base 3. One is a method of forming the polyimide resin layer 30 by electrodepositing a coating after forming the shape of the sub-base 3 body. In this case, in the process of forming the shape of the thin sub-base 3 body, there is stamping or etching. Stamping is advantageous in terms of cost, and etching is advantageous in terms of processing accuracy. In addition, the polyimide resin layer 30 is formed on both sides. The other is a method of forming the polyimide resin layer 30 on a thin plate before forming the shape of the sub-base 3 body, and then forming the shape of the sub-base 3 by stamping. In this case, etching cannot be used. In addition, a spray coating method or a lamination method can be used in the formation of the polyimide resin layer 30, and the polyimide resin layer 30 can be formed on one side or both sides.

[0037] The above are the details of the configuration of this embodiment. In the OIS lens driving device 1 as an optical component driving device in this embodiment, the metal sub-base 3 body is covered with the polyimide resin layer 30. Therefore, when the lower plate 4 is adhesively fixed to the sub-base 3, the polyimide resin layer 30 has insulation properties and strong adhesive strength with the adhesive. Therefore, it is possible to provide an optical component driving device, a camera device, and an electronic device composed of an insulating material having strong adhesive strength with the adhesive.

[0038] Here, the inventors of the present application conducted the following experiment in order to confirm to what extent the adhesive strength between the lower plate 4 and the sub-base 3 can be improved by using polyimide as the insulating material on the surface of the sub-base 3 body. The inventors selected the following materials a1 and b1 as insulating materials not including polyimide, and selected the following materials c1 and d1 as insulating materials including polyimide.

[0039] a1. Parylene

[0040] Here, in Patent Document 1, it is used as a material for an electrically insulating layer for insulating a support member from a conductive plate, and parylene is formed on the surface of the plate 91 as a test piece.

[0041] b1. PET lamination

[0042] It is obtained by laminating polyethylene terephthalate on the surface of the plate 91 by a lamination method.

[0043] c1. PI spray

[0044] It is obtained by spraying polyimide on the surface of the plate 91.

[0045] d1. PI lamination

[0046] It is obtained by forming polyimide on the surface of the board 91 by lamination method.

[0047] The inventors, as Figure 4 shown, overlap a part of the board 91 with materials a1, b1, c1, and d1 formed on its surface and the SUS304 stainless steel board 92 which is the material used in the actual lower board 4, and use the adhesive used in actual production to bond the overlapping part 93 to form a board as the tensile test board. On this basis, for the tensile test boards of materials a1, b1, c1, and d1, five tensile tests are carried out using a tensile shear testing machine, and the peel strength (N / square centimeter) per unit area is recorded. The recording results are shown in the following table. In addition, Figure 5 A bar chart showing the peel strength per unit area of materials a1, b1, and c1.

[0048]

Table 1

[0049]

[0050]

[0051] ※ The "-" in the table indicates that due to the failure of the peel strength measurement, the peel strength per unit area cannot be obtained.

[0052] According to the above table and Figure 5 the recording results, it can be seen that the bonding strength per unit area of parylene and PET lamination is roughly the same, but the bonding strength per unit area of PI spray is less than twice that of parylene and PET lamination.

[0053] In addition, after the tensile test board is peeled off in the tensile test, the inventors observe which of parylene, PET lamination, and PI spray board remains the adhesive with the SUS304 stainless steel board, and take pictures of the peeled surface of the board. Figure 6 、 Figure 7 and Figure 8 are the photographed pictures of the peeled surfaces of parylene, PET lamination, and PI spray from the first to the fifth tensile tests.

[0054] According to Figure 6 、 Figure 7 and Figure 8 the photographed pictures, all the adhesives remain on the side of the SUS304 stainless steel board in parylene and PET lamination. That is, the bonding strength between parylene and PET lamination and the adhesive is weaker than the bonding strength between SUS304 stainless steel and the adhesive in all 5 times.

[0055] In contrast, in the case of PI spraying, almost all of the adhesive remains on the side of the spraying plate where polyimide has been sprayed. That is, the adhesive strength between PI spraying and the adhesive is stronger than the adhesive strength between SUS304 stainless steel and the adhesive in all five times.

[0056] Therefore, the peel strength shown in Table 1 for parylene and PET lamination represents the peel strength between parylene and PET lamination and the adhesive. However, the peel strength of PI spraying (and PI lamination) does not represent the peel strength between PI spraying (and PI lamination) and the adhesive, but rather can be said to represent the peel strength between SUS304 stainless steel and the adhesive. That is, the actual peel strength between PI spraying (and PI lamination) and the adhesive is even greater than the figures in Table 1.

[0057] Based on the above experimental results, it was confirmed that when the insulating material on the surface of the sub-base 3 body is polyimide, the adhesive strength with the adhesive is increased to the level of parylene or PET, or compared to that, increased to the extent that the adhesive with SUS304 stainless steel with strong adhesive strength peels off first.

[0058]

Description of Reference Numerals

[0059] 1 OIS lens driving device; 2 base; 3 sub-base; 4 lower plate; 5 sliding member; 6 upper plate; 7 SMA wire; 10 camera device; 11 lens body; 12 image sensor; 13 AF actuator; 27, 37, 67 through holes; 30 polyimide resin layer; 31 sliding member mounting portion; 40-1, 40-2, 40-3, 40-4, 40-5, 40-6 plates; 45 cutout; 48, 68 crimping portions; 60 body portion; 61 connecting piece; 65 wrist portion; 99 smartphone.

Claims

1. An optical component driving device, characterized in that, Comprising: A metal base, in a square shape with a through-hole at the center; A sub-base, fixed to the base, in a square shape with a through-hole at the center and multiple sliding members fixed to the sliding member mounting portion; A metal lower plate, having a hole shape corresponding to the through-hole of the sub-base and a square outer shape corresponding to the outer shape of the sub-base as a whole, and comprising multiple plates, and fixed to the upper surface of the sub-base using an adhesive; A square upper plate, having a through-hole at the center, having two arms electrically connected to two plates of the lower plate, and sliding on the lower plate while sandwiching the multiple sliding members; And Multiple SMA wires, with both ends fixed to the hook portions of the plates in the lower plate and the hook portions of the upper plate, and causing the upper plate to move while sandwiching the sliding members, One hook portion of the plate of the lower plate is formed on each plate, and two are provided respectively at two corner portions of a diagonal of the lower plate, and two hook portions of the plate of the upper plate are provided respectively at two corner portions of the other diagonal of the upper plate, so that the hook portions of the plates of the lower plate and the hook portions of the plates of the upper plate are arranged at the four corners of the square shape, The sub-base has a metal sub-base body and an insulating resin layer formed to cover the upper surface of the sub-base body, Any of the plates of the lower plate provided with a hook portion extends from the corner of the square shape provided with the hook portion to at least the center of the side of the square shape of the plate to the terminal, and is fixed to the upper surface of the sub-base.

2. The optical component driving device according to claim 1, wherein Any of the plates of the lower plate provided with a hook portion extends to at least the center of the side of the square shape in the direction in which the SMA wire fixed to the hook portion extends, and is fixed to the upper surface of the sub-base.

3. An optical component driving device, characterized in that, Comprising: A sub-base, in a square shape with a through-hole at the center and multiple sliding members fixed to the sliding member mounting portion; A metal lower plate, having a hole shape corresponding to the through-hole of the sub-base and a square outer shape corresponding to the outer shape of the sub-base as a whole, and comprising multiple plates, and fixed to the upper surface of the sub-base using an adhesive; A square upper plate, having a through-hole at the center, having two arms electrically connected to two plates of the lower plate, and sliding on the lower plate while sandwiching the multiple sliding members; And Multiple SMA wires, with both ends fixed to the hook portions of the plates in the lower plate and the hook portions of the upper plate, and causing the upper plate to move while sandwiching the sliding members, One hook portion of the plate of the lower plate is formed on each plate, and two are provided respectively at two corner portions of a diagonal of the lower plate, and two hook portions of the plate of the upper plate are provided respectively at two corner portions of the other diagonal of the upper plate, so that the hook portions of the plates of the lower plate and the hook portions of the plates of the upper plate are arranged at the four corners of the square shape, The sub-base has a sub-base body made of metal and an insulating resin layer formed so as to cover the upper surface of the sub-base body. Any one of the plate pieces provided with the hook portions in the lower plate extends at least to the center of the side portion of the square shape in the direction in which the SMA wire fixed to the hook portion extends, and is fixed to the upper surface of the sub-base.

4. A camera device, characterized in that, An optical component driving device according to any one of claims 1 to 3 is provided.

5. An electronic device, characterized in that, A camera device according to claim 4 is provided.

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