JP2017198753A - Imaging apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an imaging apparatus capable of accurately fixing a position, regardless of expansion and shrinkage of an adhesive agent or the like.SOLUTION: An imaging apparatus includes: a lens frame for holding a lens; an attachment that supports the lens frame to be displaceable in an optical axis direction and has a first end surface vertical to the optical axis direction; a sensor holder having a second end surface that supports the attachment, is vertical to the optical axis direction, and come in contact with the first end surface while supporting the attachment and an opening that is formed to support the lens frame; a first elastic member for applying an energizing force, in a direction substantially horizontal to the optical axis direction, to the lens frame and the attachment; and a second elastic member for applying an energizing force so as to allow the attachment to be press-bonded to the sensor holder.SELECTED DRAWING: Figure 1

Description

  One embodiment of the present invention relates to an imaging device capable of accurate position adjustment and position fixing.

  As an imaging device used for in-vehicle cameras and surveillance cameras, a lens holder that arranges and holds a plurality of lenses, a printed wiring board (sensor board) on which an imaging element is mounted, and a base that connects and fixes the lens holder and the printed wiring board Some are equipped with members. In this imaging device, the printed wiring board is fixed to the base member and the lens is held so that the central axis of the cylindrical portion of the base member (the portion that receives the lens holder) and the center of the light receiving portion of the imaging element coincide. The male screw part of the lens holder thus made is screwed into the female screw part of the cylindrical part of the base member to adjust the focus in the optical axis direction (Patent Document 1).

JP 2005-215369 A

  In the above imaging device, printed wiring is used to match the center axis (lens optical axis) of the cylindrical portion of the base member (corresponding to the sensor holder of the present invention) and the center of the light receiving portion of the imaging device (light receiving sensor). After the substrate is moved in the direction perpendicular to the optical axis and aligned, the base member and the printed wiring board are fixed with an adhesive. However, with such fixing, the adhesive between the base member and the printed wiring board expands and contracts due to changes in the surrounding environment, and the distance between the base member and the printed wiring board changes, resulting in out of focus. is there. Accordingly, there is a demand for an imaging apparatus that is less likely to be out of focus due to expansion or contraction of an adhesive or the like that adheres members. More preferably, there is a need for an imaging device that suppresses the amount of adhesive (one of the causes of defocusing due to expansion / contraction) used to bond members as much as possible.

  The present invention adopts the following means in order to solve the above problems. In the following description, in order to facilitate understanding of the invention, reference numerals and the like in the drawings are appended in parentheses, but each component of the present invention is not limited to these appendices. It should be construed broadly to the extent that contractors can technically understand.

One means of the present invention is to
A lens frame (4) for holding the lens;
An attachment (6) that supports the lens frame so as to be displaceable in the optical axis direction and has a first end face (C) perpendicular to the optical axis direction;
A second end face (C) perpendicular to the optical axis direction that contacts the first end face in a state of supporting the attachment and supporting the attachment; and an opening formed to support the lens frame; A sensor holder (2) having
A first elastic member (5) for applying an urging force in a direction substantially horizontal to the optical axis direction to the lens frame and the attachment;
A second elastic member (3) for applying an urging force to press the attachment against the sensor holder;
An imaging device.

  In the imaging apparatus having the above-described configuration, the lens is held by the lens frame, and the lens frame is supported by the attachment and further supported by the sensor holder via the attachment. The position of the lens frame supported by the attachment is adjusted by relatively moving in the optical axis direction (for example, the Z direction), and a plane (for example, the first end surface of the attachment and the second end surface of the sensor holder abut on each other). The position is adjusted at the position C (which is the XY plane). Accordingly, the position of the lens is adjusted in the optical axis direction (for example, the Z direction) and the contact plane (for example, the XY plane) between the first end surface and the second end surface. In this way, the lens is not fixed only by the adhesive, but is fixed by the abutting surface or the like, so that it is possible to suppress the displacement of the position due to the expansion / contraction of the adhesive. Become. Thereby, even when temperature and humidity change and the adhesive expands and contracts, it is possible to configure an imaging apparatus capable of suppressing the displacement of the lens position (optical axis). Moreover, it can be set as the structure which fixes the relative position of a lens frame and an attachment firmly with a 1st elastic member. Moreover, it can be set as the structure which fixes an attachment without deviation with respect to a sensor holder by a 2nd elastic member. Furthermore, since the first elastic member and the second elastic member separate the function of preventing the lens frame from shifting and the function of pressing the attachment, the positions of the lens frame and the attachment can be firmly held. Become. In addition, this may provide an imaging apparatus that suppresses the amount of adhesive (one of the causes of defocusing due to expansion / contraction) used to bond members as much as possible.

In the imaging apparatus, preferably,
It further includes a sensor substrate (1) that is fixedly supported with respect to the sensor holder and has a sensor that receives incident light from the lens.

  According to the imaging apparatus, it is possible to prevent the incident light irradiated from the lens to the sensor from being shifted due to temperature, humidity, or the like.

In the imaging apparatus, preferably,
The lens frame and the attachment are screw-coupled so as to be relatively displaceable in the optical axis direction.

  According to the above imaging device, since the lens frame and the attachment are screw-coupled (screwed together), the relative position can be fixed with higher accuracy than the position fixing only with the adhesive.

In the imaging apparatus, preferably,
A predetermined gap is formed in a direction perpendicular to the optical axis direction between the attachment and the sensor holder.

  According to the above imaging apparatus, the attachment and the sensor holder can be configured such that the position of the attachment and the sensor holder can be adjusted in a direction (for example, XY plane) perpendicular to the optical axis direction before being reinforced and fixed with an adhesive or the like.

The exploded perspective view of an imaging device. The top view which looked at the imaging device from the to-be-photographed object side. Sectional drawing in the position of LL of an imaging device. The enlarged view of the periphery of the attachment in sectional drawing of an imaging device.

An embodiment according to the present invention will be specifically described according to the following configuration with reference to the drawings. However, the embodiment described below is merely an example of the present invention and does not limit the technical scope of the present invention. In addition, in each drawing, the same code | symbol is attached | subjected to the same component and the description may be abbreviate | omitted.
1. Embodiment 2. FIG. Supplementary matter

<1. Embodiment>
The image pickup apparatus according to the present embodiment has a configuration capable of adjusting the position on a plane perpendicular to the optical axis (also referred to as an XY plane) and performing focus adjustment (position adjustment) in the optical axis direction (Z direction). The lens position can be fixed accurately by using an adhesive or the like in an auxiliary manner while fixing the position by contact between the end faces and screw connection. Hereinafter, the configuration of the imaging apparatus of the present embodiment will be specifically described.

  FIG. 1 is an exploded perspective view of the imaging apparatus according to the present embodiment as viewed from the front side (subject side). FIG. 2 is a plan view of the imaging apparatus according to the present embodiment as viewed from the front side (subject side). FIG. 3 is a side view at the cross-sectional position of LL in FIG. 2. FIG. 4 is an enlarged view of the vicinity of the attachment 6 of FIG.

  As shown in FIGS. 1 to 3 (particularly FIG. 1), the imaging device of the present embodiment includes a sensor substrate 1, a sensor holder 2, a leaf spring 3, a lens frame 4, a compression spring 5, an attachment 6, and the like. Consists of. On the sensor substrate 1, a sensor 11, a heat generating member 12, and other electronic components are mounted. As shown in FIG. 1, the sensor substrate 1 is connected to the sensor holder 2 by screws 14 a to 14 c and the like, and a lens frame 4, a compression spring 5, and an attachment 6 are provided between the sensor substrate 1 and the sensor holder 2. Be placed. The sensor holder 2 is connected to the attachment 6 via the leaf spring 3 by screws 31a to 31d and the like.

  The attachment 6 is in contact with the sensor holder 2 at the position C in FIG. 4, and the attachment 6 is in a direction (XY direction) perpendicular to the optical axis direction in a pre-assembly state before the leaf spring 3 or adhesive is applied. It is possible to move to. The attachment 6 supports the lens frame 4 by contact at the position B in FIG. 4 and screw connection at the position A. In the pre-assembly state, the lens frame 4 is movable in the optical axis direction (Z direction) with respect to the attachment 6 by rotation at the screw coupling portion (A). In this way, the lens frame 4 is adjusted in the XYZ space in the pre-assembly state, and is assembled and fixed using the adhesive at an appropriate position. Although not described because it is not a feature of the present invention, the imaging apparatus of the present embodiment has a configuration necessary for the imaging apparatus such as an aperture mechanism and a shutter mechanism, as in the prior art.

<Sensor board 1>
The sensor substrate 1 is a substrate on which the sensor 11, the heat generating member 12, and other electronic components are mounted, and is formed of a resin or the like. The sensor 11 is, for example, an image sensor such as a CMOS or CCD. The sensor 11 receives incident light transmitted through a lens from a subject, converts the light into an electric signal (photoelectric conversion), and converts the light into a semiconductor device or the like. Output to the control unit. The center portion of the sensor 11 is adjusted to be the optical axis. The sensor 11 may include other members such as a cover glass, and even in this case, the sensor 11 is referred to as a sensor. The sensor substrate 1 is connected and fixed to the sensor holder 2 by screws 14a to 14c and the like.

  The heat generating member 12 is an image processing device such as an ISP (Image Signal Processor) that processes an imaging signal output from the sensor 11, for example, and is a semiconductor device such as a DSP or an ASIC. In the conventional sensor, the ISP is generally configured integrally with the sensor. However, in recent years, the ISP is often configured differently from the sensor because of the necessity of heat dissipation. In such an ISP, image processing with a high processing load is performed, and thus heat generation is particularly high among electronic components mounted on the sensor substrate 1. The heat generating member 12 is not necessarily an ISP, and an element having a high need for heat dissipation is selected. Further, the heat generating member 12 is not necessarily limited to one member, and a plurality of members may be targeted.

  The heat generating member 12 is fixed to the sensor substrate 1 with solder or the like, and a heat dissipation buffer 13 is mounted thereon (see the subject side) (see FIG. 4). The heat dissipation buffer 13 is a material having high thermal conductivity and elasticity, and is formed, for example, in a substantially rectangular plate shape. One surface thereof is in contact with the heat generating member, and the other surface is in close contact with the base member 3 elastically. ing. Both surfaces of the heat dissipation buffer 13 are formed in an area and shape so as to cover the front surface of the heat generating member 12. As the heat dissipation buffer 13, a general heat dissipation sheet or heat dissipation grease is used.

<Sensor holder 2>
The sensor holder 2 has a circular opening at the center, and accommodates the lens frame 4, the compression spring 5, and the attachment 6 in this opening. The sensor holder 2 is connected to the sensor substrate 1 with screws 14a to 14c and the like. A lens supported by the lens frame 4 is located in the opening, and this opening is an opening through which incident light passes. The front surface side (subject side) of the sensor holder 2 is formed with an end surface 2a and an end surface 2b at a position lowered from the end surface 2a to the sensor 11 side. The end face 2b is formed flat on a plane (XY plane) perpendicular to the optical axis, and is in contact with an attachment 6 (described later) at a position C (see FIG. 4). The end surface 2b is fixed by applying an adhesive during assembly. The end surface 2b is an example of a second end surface of the present invention.

  The sensor holder 2 is made of a metal material having high thermal conductivity and rigidity such as aluminum. A part of the surface of the sensor holder 2 facing the sensor substrate 1 is in contact with the heat dissipation buffer material 13. Asperities 21 are formed on the surface of the sensor holder 2 on the subject side as shown in FIGS. Considering the bottom 21a of the unevenness 21 as a reference, it can be said that the rib shape is formed by the unevenness 21. In the present embodiment, a structure having a shape similar to a wall for reinforcement while the unevenness is formed is called a rib shape. By forming the rib shape by such irregularities 21, the surface area in contact with the outside air is wider than the apparent surface area where the rib shape is not formed. In particular, in the portion corresponding to the surface area of the heat generating member 12 (the area where the heat generating member 12 contacts the sensor holder 2 via the heat radiating buffer 13 and the vicinity thereof) where the necessity of heat dissipation is high, the surface area is the apparent surface area. The rib shape is formed to be 2 to 3 times. By forming the rib shape on the sensor holder 2, the surface area in contact with the outside air is widened, and the necessary strength is ensured while the amount of the necessary material is reduced.

  The “surface region of the heat generating member” means (1) a region where the heat generating member 12 is in contact with the base member 3 (in some cases through the heat dissipation buffer 13), or (2) the heat generating member 12 is (in some cases). The region that contacts the base member 3 and the region in the vicinity of the region that contacts the base member 3).

  As described above, in the imaging apparatus of the present embodiment, the heat dissipation buffer material 13 is disposed on the heat generating member 12 mounted on the sensor substrate 1 and brought into contact with the sensor holder 2, and the heat of the heat generating member 12 is converted to the heat dissipation buffer material. 13 is conducted to the sensor holder 2 through 13 to dissipate heat from the sensor holder 2 having a large surface area. Thereby, the heat generated from the heat generating member 12 can be efficiently radiated. Moreover, the rib shape formed in the sensor holder 2 functions like a heat radiating fin, and heat can be efficiently radiated. Furthermore, since the rib shape is formed on the sensor holder 2, it is possible to reduce the size and weight of the imaging apparatus, shorten the molding time of the sensor holder 2, and reduce the material cost.

  Moreover, the rib shape by the unevenness | corrugation 21 formed in the sensor holder 2 has a surface area of 2 to 3 times with respect to the apparent surface area when the rib shape is not formed. As a result, the heat of the heat generating member 12 can be radiated more effectively.

<Leaf spring 3>
The leaf spring 3 is a leaf spring formed of a metal with a circular opening formed in the center, and the attachment 6 is attached to the front side of the sensor holder 2 by fixing the four corners with screws 31a to 31d. An urging force in the sensor direction is applied so as to be elastically pressed against the sensor holder 2. The leaf spring 3 is an example of a second elastic member of the present invention.

<Lens frame 4>
The lens frame 4 is formed in a cylindrical shape so as to support one or a plurality of (generally a plurality of) lenses, and is connected to the attachment 6 by screw coupling (screwing) at a position A in FIG. ing. More specifically, as shown in the sectional view of FIG. 4, the screw thread formed on the lens frame 4 is screw-coupled with the screw thread of the attachment 6. The lens frame 4 and the attachment 6 are in contact with each other at the position B. Note that the lens frame 4 and the attachment 6 do not have to be completely in contact with each other at the contact position (B), and may be slightly separated from each other. In the assembled state, the lens frame 4 and the attachment 6 are bonded to the contact position (B). The agent is applied to assist fixing by screw connection.

<Compression spring 5>
The compression spring 5 is a coil spring formed of metal or the like. As shown in FIGS. 3 and 4 (particularly FIG. 4), the compression spring 5 is arranged on the inner side (optical axis side) of the sensor holder 2 and the attachment 6 and on the outer side of the lens frame 4. One end on the subject side is in contact with the attachment 6, and one end on the sensor side is in contact with the lens frame 4. By being arranged in this way, the compression spring 5 applies an urging force toward the subject side with respect to the attachment 6 and applies an urging force toward the sensor side with respect to the lens frame 4. The biasing force of the compression spring 5 suppresses rattling (positional deviation) of the lens frame 4. The compression spring 5 is an example of a first elastic member of the present invention.

<Attachment 6>
The attachment 6 is formed in a cylindrical shape and is disposed between the sensor holder 2 and the lens frame 4. The attachment 6 has a large-diameter portion that protrudes outward (on the side opposite to the optical axis) from the cylindrical portion. The surface of the large-diameter portion on the sensor side is the end surface 2b of the sensor holder 2 and C It contacts at the position of. This surface is formed flat on a plane (XY plane) perpendicular to the optical axis, and is an example of the second end surface of the present invention. A surface of the attachment 6 opposite to the surface (second end surface) in the large diameter portion is in contact with the leaf spring 3 and is urged by the leaf spring 3 in the sensor direction. Further, on the inner diameter side of the attachment 6, a screw thread is formed at a position A in FIG. 4 and is configured to be coupled to the screw thread of the lens frame 4 by screwing. Further, a contact surface is formed at the position B in FIG. 4 on the inner diameter side of the attachment 6 and is in contact with the outer peripheral surface of the lens frame 4. An adhesive is applied to the abutting surface and fixed during assembly.

  When the imaging apparatus is assembled, the sensor substrate 1, the lens frame 4, the compression spring 5, and the attachment 6 are incorporated into the sensor holder 2, and the leaf spring 3 is attached by screws 31a to 31d. At this time, the attachment 6 is screw-coupled with the lens frame 4 by the screw thread (A), and moves in the optical axis direction (Z direction) by rotating the lens frame 4. Further, the attachment 6 can move freely to some extent in the direction perpendicular to the optical axis (XY direction) with respect to the sensor holder 2. In this state, the attachment 6 is moved in the XY directions to adjust the positions of the sensor 11 and the lens frame 4 with respect to the optical axis, and the lens frame 4 is further rotated to adjust the position in the Z direction. When the position in the XY direction is determined, an adhesive is applied to the contact surface C between the sensor holder 2 and the attachment 6. When the position in the Z direction is determined, an adhesive is applied to the contact portion (B) between the lens frame 4 and the attachment 6.

  As described above, in the imaging apparatus according to the present embodiment, the lens is supported by the lens frame 4, and the lens frame 4 is supported by the sensor holder 2 through the attachment 6 while being supported by the attachment 6. The lens frame 4 supported by the attachment 6 is adjusted in position by relatively moving in the optical axis direction (for example, the Z direction), and further, a contact surface between the sensor holder 2 and the attachment 6 (position C in FIG. 4). For example, the XY plane). Thereby, the position of the lens is adjusted in the optical axis direction (for example, Z direction) and the contact surface (for example, XY plane). As described above, the lens is not fixed only by the adhesive, but is fixed by the contact surface and the screw fixing, so that it is possible to suppress the displacement of the position due to the expansion and contraction of the adhesive. Is possible. Thereby, even when the adhesive is slightly displaced due to temperature or humidity, it is possible to configure an imaging device capable of accurately suppressing the displacement of the lens position (optical axis). Further, the relative position between the lens frame 4 and the attachment 6 can be firmly fixed by the compression spring 5. Further, the attachment 6 can be fixed to the sensor holder 2 without displacement by the leaf spring 3. Furthermore, since the compression spring 5 and the leaf spring 3 separate the function of preventing the lens frame from shifting and the function of pressing the attachment, the positions of the lens frame and the attachment can be firmly held. In addition, this may provide an imaging apparatus that suppresses the amount of adhesive (one of the causes of defocusing due to expansion / contraction) used to bond members as much as possible.

  Further, since the compression of the lens frame 4 is suppressed by the compression spring 5, it is possible to adopt a configuration that can cope with an adjustment with a longer stroke when adjusting the position in the Z direction.

<2. Supplementary items>
The specific description of the embodiment of the present invention has been given above. In the above description, the description is merely an embodiment, and the scope of the present invention is not limited to this embodiment, but is broadly interpreted to the extent that a person skilled in the art can grasp.

  For example, in the above embodiment, the attachment 6 and the lens frame 4 are connected by screw connection (screwing), but may be connected by another method that is relatively movable in the optical axis direction.

  The term “perpendicular” in the case of “perpendicular to the optical axis direction” in the present invention is ideally 90 °, but “perpendicular” from the viewpoint that a desired position adjustment or the like may be achieved. The lower limit of the allowable range of the angle is preferably 88 °, more preferably 89 °, and the upper limit of the allowable range is preferably 92 °, more preferably 91 °.

  In the present invention, “substantially horizontal” in the case of “substantially horizontal to the optical axis direction” is ideally horizontal (0 ° with respect to the optical axis), but for desired position adjustment and position fixing. The allowable range of “substantially horizontal” is preferably within 10 ° with respect to the optical axis, more preferably 5 ° with respect to the optical axis. Within.

  INDUSTRIAL APPLICABILITY The present invention is effectively used as an in-vehicle imaging device that requires particularly high-precision position adjustment.

DESCRIPTION OF SYMBOLS 1 ... Sensor board 11 ... Sensor 12 ... Heat generating member 13 ... Heat dissipation buffer material 14a-14c ... Screw 2 ... Sensor holder 3 ... Base member 31a-31d ... Screw 4 ... Lens frame 5 ... Compression spring 6 ... Attachment

Claims (4)

A lens frame for holding the lens;
An attachment that supports the lens frame so as to be displaceable in the optical axis direction, and has a first end face perpendicular to the optical axis direction;
A second end face that is perpendicular to the optical axis direction that contacts the first end face in a state in which the attachment is supported; and an opening that is formed to support the lens frame. A sensor holder,
A first elastic member that applies a biasing force in a direction substantially parallel to the optical axis direction to the lens frame and the attachment;
A second elastic member for applying an urging force to press the attachment against the sensor holder,
Imaging device. A sensor substrate having a sensor fixedly supported with respect to the sensor holder and receiving incident light from the lens;
The imaging device according to claim 1. The lens frame and the attachment are screwed together so as to be relatively displaceable in the optical axis direction.
The imaging device according to claim 1 or 2. A predetermined gap is formed in a direction perpendicular to the optical axis direction between the attachment and the sensor holder.
The imaging device according to any one of claims 1 to 3.

Images