JP6702787B2 - Imaging device - Google Patents

Description

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

As an image pickup device used for an in-vehicle camera, a surveillance camera, etc., a lens holder for arranging and holding a plurality of lenses, a printed wiring board (sensor substrate) on which an image pickup element is mounted, a base for connecting and fixing the lens holder and the printed wiring board Some are equipped with members and the like. In this image pickup 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 (the portion that receives the lens holder) of the base member and the center of the light receiving portion of the image pickup element match. The male screw portion of the lens holder is screwed into the female screw portion of the cylindrical portion of the base member to adjust the focus in the optical axis direction (Patent Document 1).

JP, 2005-215369, A

In the above-mentioned image pickup device, since the center axis of the cylindrical portion (optical axis of the lens) of the base member (corresponding to the lens holder of the present invention) and the center of the light receiving portion of the image pickup element (light receiving sensor) are aligned, printed wiring is used. After moving the substrate in a direction perpendicular to the optical axis to align the substrate, the base member and the printed wiring board are fixed with an adhesive. However, in such a fixing method, 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, causing a focus shift. There is. Therefore, there has been a demand for an imaging device that is less likely to be out of focus due to expansion and contraction of an adhesive or the like that bonds members.

The present invention adopts the following means in order to solve the above problems. In the following description, reference numerals and the like in the drawings are added in parentheses in order to facilitate understanding of the invention, but each constituent element of the present invention is not limited to these additions. It should be broadly interpreted to the extent technically understandable by a trader.

One means of the present invention is
A lens frame (2) for holding the lens,
An attachment (5) that supports the lens frame so as to be displaceable in the optical axis direction and has a first end face that is perpendicular to the optical axis direction;
A lens holder having a second end surface which supports the attachment and which is in contact with the first end surface in a state where the attachment is supported and which is perpendicular to the optical axis direction, and an opening formed in the second end surface. (4),
An image pickup apparatus comprising: the lens frame and an elastic member (3) that applies a biasing force to the lens holder in a direction substantially horizontal to the optical axis direction.

In the image pickup apparatus having the above configuration, the lens is held by the lens frame, and the lens frame is supported by the attachment while being further supported by the lens holder via the attachment. The lens frame supported by the attachment is positionally adjusted by relatively moving in the optical axis direction (for example, the Z direction), and further, the first end surface of the lens holder is in contact with the second end surface of the attachment (for example, XY). Position). Thereby, 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. Thus, the position of the lens is not fixed only by the adhesive, but the position of the lens is fixed by the abutting surface, etc., so that it is possible to prevent the lens from being displaced due to expansion and contraction of the adhesive. Become. This makes it possible to configure an imaging device that can suppress the displacement of the lens position (optical axis) even when the adhesive expands or contracts due to changes in temperature or humidity. Further, the elastic member can firmly fix the relative position between the lens frame and the lens holder.

In the above imaging device, preferably,
A sensor substrate fixedly supported by the lens holder and having a sensor for receiving incident light from the lens is further provided.

According to the above-described image pickup device, it is possible to prevent the incident light emitted from the lens from the sensor from deviating due to temperature or humidity.

In the above imaging device, preferably,
The lens frame and the attachment are screwed so as to be relatively displaceable in the optical axis direction.

According to the above-described image pickup device, the lens frame and the attachment are screwed (screwed) to each other, so that the relative position can be fixed more accurately than the position fixing using only the adhesive.

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

According to the above-described imaging device, the attachment and the lens holder can be configured to be positionally adjustable in a direction (eg, XY plane) perpendicular to the optical axis direction before being reinforced and fixed with an adhesive or the like.

FIG. 3 is an external perspective view of the imaging device. The exploded perspective view of an imaging device. FIG. 3 is a cross-sectional view of an imaging device.

Embodiments according to the present invention will be specifically described with reference to the drawings according to the following configurations. 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 each drawing, the same components are designated by the same reference numerals, and the description thereof may be omitted.
1. Embodiment 2. Supplementary information

<1. Embodiment 1>
The image pickup apparatus according to the present embodiment has a configuration capable of performing position adjustment on a plane (also referred to as an XY plane) perpendicular to the optical axis and performing focus adjustment (position adjustment) in the optical axis direction (Z direction). It is characterized in that the lens position can be accurately fixed by auxiliary use of an adhesive or the like while fixing the positions by contact between the end faces and screwing. The configuration of the image pickup apparatus according to this embodiment will be specifically described below.

FIG. 1 is an external perspective view of the image pickup apparatus of this embodiment as seen from the front side (subject side). FIG. 2 is an exploded perspective view of the image pickup apparatus according to the present embodiment as seen from the front side. FIG. 3 is a cross-sectional view in the longitudinal direction of the image pickup apparatus of this embodiment.

As shown in FIGS. 1 to 3, the image pickup apparatus according to this embodiment includes a sensor substrate 1, a lens frame 2, a compression spring 3, a lens holder 4, and an attachment 5. A sensor 11 and other electronic components are mounted on the sensor board 1. As shown in FIG. 1, the sensor substrate 1 is connected to the lens holder 4 with screws or the like, and the lens frame 2, the attachment 5, and the compression spring 3 are arranged between the sensor substrate 1 and the lens holder 4. ..

The attachment 5 abuts on the lens holder 4, and the attachment 5 is fixed by applying an adhesive to the abutting portion (the abutting portion between the first end surface 51 and the second end surface 41, see FIG. 3 ). In the pre-assembly state before the adhesive is applied, the attachment 5 is movable in a direction (XY direction) perpendicular to the optical axis direction. The attachment 5 supports the lens frame 2 by abutting and screwing (threads 22 and 52). In the pre-assembly state before the adhesive is applied, the lens frame 2 is movable in the optical axis direction (Z direction) with respect to the attachment 5 by the rotation of the screw coupling portion. In this way, the lens frame 2 is adjusted in the XYZ space in the pre-assembly state, and assembled and fixed using an adhesive at an appropriate position. It should be noted that although not described because it is not a characteristic part of the present invention, the image pickup apparatus of the present embodiment is provided with a configuration necessary for the image pickup apparatus such as a diaphragm mechanism and a shutter mechanism, as in the related art.

<Sensor board 1>
The sensor substrate 1 is a substrate on which the sensor 11 and other electronic components are mounted and is made of resin or the like. The sensor 11 is, for example, an image pickup device such as a CMOS or a CCD, receives the incident light that has entered from the subject through the lens, converts the light into an electric signal (photoelectric conversion), and uses a semiconductor device or the like. Output to the control unit. The central 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, it is called a sensor. The sensor substrate 1 is connected and fixed to the lens holder 4 with screws or the like.

<Lens frame 2>
The lens frame 2 is formed in a cylindrical shape so as to support one or a plurality (generally a plurality) of lenses, and is connected to the lens holder 4 by screw connection (screw engagement). More specifically, as shown in the sectional view of FIG. 3, the screw thread 22 formed on the lens frame 2 is screwed to the screw thread 52 of the attachment 5. The first outer peripheral surface 23 of the lens frame 2 is in contact with the first contact surface 53 of the attachment 5, and the second outer peripheral surface 24 of the lens frame 2 is in contact with the second contact surface 54 of the attachment 5. There is. The first outer peripheral surface 23 and the first abutting surface 53, and the second outer peripheral surface 24 and the second abutting surface 54 do not have to be completely in contact with each other, and may be slightly separated from each other. In this state, an adhesive is applied to these abutting portions (or adjacent portions) to assist in fixing by screw connection.

<Compression spring 3>
The compression spring 3 is a coil spring made of metal or the like. As shown in FIG. 3, the compression spring 3 is arranged inside the lens holder 4 (on the optical axis side) and outside the attachment 5 and the lens frame 2, and one end of the subject side thereof is the lens holder 4 , And one end on the sensor side is in contact with the lens frame 2. By being arranged in this way, the compression spring 3 applies an urging force to the lens holder 4 toward the subject side and an urging force to the lens frame 2 toward the sensor side. The biasing force of the compression spring 3 suppresses rattling (positional displacement) of the lens frame 2 (and indirectly the attachment 5).

<Lens holder 4>
The lens holder 4 has a circular opening in the center, and accommodates the lens frame 2, the compression spring 3, and the attachment 5 while supporting them in this opening. A lens supported by the lens frame 2 is located in the opening, and the opening serves as an opening through which incident light passes. The front surface (subject side) of the lens holder 4 is formed with a flat surface (may be referred to as a second end surface 41), and the second end surface 41 is in contact with a first end surface 51 of the attachment 5 described later. .. The second end surface 41 is formed flat on a plane (XY plane) perpendicular to the optical axis. An adhesive is applied to the surface where the first end surface 51 and the second end surface 41 come into contact with each other and fixed at the time of assembly.

<Attachment 5>
The attachment 5 is formed in a cylindrical shape and is arranged between the lens holder 4 and the lens frame 2. The attachment 5 has a large-diameter portion that projects from the cylindrical portion, and the sensor-side surface of this large-diameter portion (sometimes called the first end surface 51) is the second end surface of the lens holder 4 described above. 41 (see FIG. 3). The first end surface 51 is formed flat on a plane (XY plane) perpendicular to the optical axis. Further, a screw thread 52 is formed on the inner diameter side of the attachment 5 and is configured to be screwed with the screw thread 22 of the lens frame 2. Further, a first contact surface 53 and a second contact surface 54 are formed on the inner diameter side of the attachment 5 and contact the first outer peripheral surface 23 and the second outer peripheral surface 24 of the lens frame 2, respectively.

When the imaging device is assembled, the sensor substrate 1, the lens frame 2, the compression spring 3, and the attachment 5 are assembled to the lens holder 4. At this time, the attachment 5 is screwed to the lens frame 2 by the threads (52 and 22), and is rotated in the optical axis direction (Z direction) by rotating the lens frame 2. Further, the attachment 5 is movable to some extent in the direction (XY direction) perpendicular to the optical axis with respect to the lens holder 4. In this state, the attachment is moved in the XY directions to adjust the positions of the sensor 11 and the lens of the lens frame 2 with respect to the optical axis, and further the lens frame 2 is rotated to adjust the position in the Z direction. When the position in the XY direction is determined, the contact surface between the lens holder 4 and the attachment 5 (contact portion between the first end surface 51 and the second end surface 41) is coated with an adhesive. Further, when the position in the Z direction is determined, the contact portion between the lens frame 2 and the attachment 5 (the contact portion between the first outer peripheral surface 23 of the lens frame 2 and the first contact surface 53 of the attachment 5, and the lens frame). An adhesive is applied to a contact portion between the second outer peripheral surface 24 of the second member 2 and the second contact surface 54 of the attachment 5).

As described above, in the image pickup apparatus according to the present embodiment, the lens is held by the lens frame 2, and the lens frame 2 is supported by the attachment 5 while being further supported by the lens holder 4 via the attachment 5. The lens frame 2 supported by the attachment 5 is positionally adjusted by relatively moving in the optical axis direction (for example, the Z direction), and the second end surface 41 of the lens holder 4 and the second end surface 51 of the attachment 5 are separated from each other. The position is adjusted on a contacting plane (for example, an XY plane). Thereby, the position of the lens is adjusted in the optical axis direction (for example, Z direction) and the contact plane (for example, XY plane) between the first end surface 51 and the second end surface 41. Thus, the position of the lens is not fixed only by the adhesive, but the position is fixed by the abutment surface and the screw fixing. Therefore, the displacement of the lens due to expansion and contraction of the adhesive is suppressed. Is possible. This makes it possible to configure an imaging device that can accurately suppress the displacement of the lens position (optical axis) even when the adhesive is slightly displaced due to temperature or humidity. Further, the compression spring 3 can firmly fix the relative position between the lens frame 2 and the lens holder 4.

Further, in the imaging device of the present embodiment, since the compression spring 3 is not exposed to the outside, it is possible to prevent the compression spring 3 from being deformed due to abrupt contact or the like during assembly and not properly functioning as a biasing member. Has become.

<2. Supplementary items>
Heretofore, a specific description has been given of the embodiment of the present invention. The above description is merely an embodiment, and the scope of the present invention is not limited to this embodiment, and is broadly construed to a range that can be grasped by those skilled in the art.

For example, in the above-described embodiment, the attachment 5 and the lens frame 2 are connected by screw connection (screw engagement), but may be connected by another method that is relatively movable in the optical axis direction.

The "first end face perpendicular to the optical axis direction" described in this specification and the like (including the claims) is "perpendicular", but ideally 90°, but a desired position From the viewpoint that adjustment etc. can be achieved, the lower limit of the allowable range of the “vertical” angle is preferably 88°, more preferably 89°, and the upper limit of the allowable range is preferably 92°, more preferably It is 91°.

Although it is "perpendicular" of the "second end face perpendicular to the optical axis direction" described in this specification and the like (including claims), it is ideally 90°, but a desired position From the viewpoint that adjustment etc. can be achieved, the lower limit of the allowable range of the “vertical” angle is preferably 88°, more preferably 89°, and the upper limit of the allowable range is preferably 92°, more preferably It is 91°.

Although it is “substantially horizontal” of “urging force in the direction substantially horizontal to the optical axis direction” described in this specification and the like (including claims), it is horizontal (0° with respect to the optical axis). Is ideal, but from the viewpoint that it is possible to achieve desired position adjustment and bias for position fixing, the “substantially horizontal” tolerance range is preferably 10 degrees with respect to the optical axis. The angle is within °, more preferably within 5° with respect to the optical axis.

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

DESCRIPTION OF SYMBOLS 1... Sensor substrate 11... Sensor 2... Lens frame 22... Threads 23, 24... Outer peripheral surface 3... Compression spring 4... Lens holder 41... End surface 5... Attachment 51... End surface 52... Threads 53, 54... Contact surface

Claims (3)

A lens frame that holds the lens,
An attachment that supports the lens frame so as to be displaceable in the optical axis direction, and has a first end surface that is perpendicular to the optical axis direction,
A second end face that supports the attachment and is in contact with the first end face in a state where the attachment is supported and is perpendicular to the optical axis direction, and the lens that is formed on the second end face and is supported by the attachment. A lens holder having an opening into which the frame is inserted ,
A sensor substrate fixedly supported with respect to the lens holder and having a sensor for receiving incident light from the lens;
One end is in contact with the lens frame , the other end is in contact with the lens holder , is arranged in the lens holder so as to surround the outer periphery of the lens frame , and is a direction toward the sensor with respect to the lens frame . And a coil spring that applies a biasing force in a direction substantially parallel to the optical axis direction. The lens frame and the attachment are screwed so as to be relatively displaceable in the optical axis direction,
The image pickup apparatus according to claim 1 . A predetermined gap is formed between the attachment and the lens holder in a direction perpendicular to the optical axis direction,
The imaging apparatus according to claim 1 or claim 2.

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