JP2012016041A - Imaging device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an imaging device capable of suppressing a thickness in an optical-axis direction and preventing entry of a foreign matter such as dust or the like to an image sensing face without applying an unnecessary force to an image sensing element.SOLUTION: A mask member 2, a low-pass filter 3, an image sensing element protective member 5, an image sensing element 6, a holding member 8 and a flexible printed circuit board 7 are built in a CCD holder 1. The image sensing element protective member 5 comprises an elastic member such as a rubber, and is formed in a picture frame shape with an outer edge section extended in a skirt shape towards an inner edge section opposed to the edge section of the low-pass filter 3 and the holding member 8. The image sensing element protective member 5 is arranged between the low-pass filter 3 and the holding member 8 so that an inner edge section is abutted against an edge section of the low-pass filter 3 and the outer edge section against the holding member 8, respectively. The image sensing element protective member 5 forms a storage space storing an image sensing element 6 separately from the outside in cooperation with the low-pass filter 3 and the holding member 8.

Description

  The present invention relates to an imaging apparatus such as a digital camera.

  In recent years, digital cameras using a memory as a recording medium are becoming widespread instead of film cameras using a silver salt film as a recording medium. This digital camera uses an image sensor such as a CCD or CMOS. In this digital camera, an infrared cut filter for cutting infrared light, a low-pass filter for preventing the occurrence of moiré and false colors in a captured image, and the like are provided. Further, a low pass filter having an infrared cut coating on the surface may be used instead of the infrared cut filter. These infrared cut filters and low-pass filters are usually arranged coaxially with the image sensor.

  In such a configuration, after dropping a sheet having a mask for cutting harmful light into a box-shaped ground plate having an opening, the filter is dropped, and the filter and the ground plate are fixed with an adhesive or the like. The Then, behind the filter, an elastic member such as rubber is sandwiched between the ground plane and the protective glass on the front surface of the image sensor, so that dust, dust, and the like are generated from the outer periphery of the image sensor to the imaging surface of the image sensor. Intrusion is prevented.

  Details of the holding structure for the image sensor in the above-described configuration will be described in detail with reference to FIGS. FIG. 5 is an exploded perspective view showing a conventional image sensor holding structure. FIG. 6 is a longitudinal sectional view showing a holding structure of the image sensor shown in FIG.

  As shown in FIG. 5 and FIG. 6, the digital camera includes a CCD holder 10 provided so that the opening is coaxial with the optical axis. In the CCD holder 10, a mask member 11, a low-pass filter 12, an image sensor 14, a flexible printed board 15 and a holding member 16 are incorporated. The mask member 11 is a member for determining the amount of light incident on the imaging surface of the imaging element 14 from the back surface and blocking harmful light. The low-pass filter 12 is a filter for cutting light in a predetermined band, and is disposed on the back side of the mask member 11. The mask member 11 and the low-pass filter 12 are arranged on the CCD holder 10 so as to be coaxial with the opening of the CCD holder 10.

  The imaging element 14 is composed of an element such as a CCD, and is disposed on the back side of the low-pass filter 12. The flexible printed circuit board 15 is a board for transmitting and receiving signals to and from the image sensor 14 and is electrically connected to the image sensor 14. The flexible printed board 15 is disposed on the back side of the image sensor 14 and is integrally fixed to the image sensor 14 by soldering. The holding member 16 is disposed on the back side of the flexible printed board 15 and is fixed to the flexible printed board 15 with an adhesive. The holding member 16 is attached to the CCD holder 10 with a plurality of screws 18 so that the image sensor 14 is coaxial with the low-pass filter 12.

  Here, a plurality of spring members 17 are arranged between the holding member 16 and the CCD holder 10, and the holding member 16 is attached to the CCD holder 10 against the spring force of each spring member 17. Yes.

  An elastic member 13 made of a rubber material or the like is sandwiched between the low pass filter 12 and the image sensor 14. As shown in FIG. 6, the elastic member 13 is compressed between the CCD holder 10 and the image sensor 14 and functions as a seal member that seals the gap between the low-pass filter 12 and the image sensor 14. Thereby, entry of dust and the like into the imaging surface of the imaging element 14 from the outside is prevented.

  In the case of such a holding structure, since the elastic member 13 is sandwiched between the CCD holder 10 and the image sensor 14, the distance for sandwiching the elastic member 13 is between the CCD holder 10 and the image sensor 14. is necessary. This is a factor that prevents the digital camera from being thinned (reducing the thickness of the main body in the optical axis direction).

  Further, a repulsive force generated by the compression of the elastic member 13 is always applied to the image sensor 14. Usually, since the imaging device 14 does not have high strength, there is a possibility that the imaging device 14 may be distorted by the above force.

  Therefore, in order to reduce the thickness in the optical axis direction, there has been proposed a holding structure used by a low-pass filter holder formed separately from the CCD holder (see Patent Document 1).

  Further, in order to reduce the thickness in the optical axis direction and prevent the repulsive force from being applied by the elastic member, a holding structure has been proposed in which the CCD and the filter are attached and integrated, and the periphery is covered with the elastic member. (See Patent Document 2).

JP 2006-67356 A JP 2005-12334 A

  However, in the case of the former holding structure among the holding structures described above, the CCD rubber (elastic member) is disposed between the CCD and the low-pass filter, so that the repulsive force by the CCD rubber is prevented from being applied. I can't.

  On the other hand, in the case of the latter holding structure, the filter is affixed to the CCD, so that this configuration is hardly general.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an imaging device that can prevent the entry of foreign matter such as dust and dust into the imaging surface without reducing the thickness in the optical axis direction and without applying extra force to the imaging device. There is to do.

  In order to achieve the above object, the present invention is arranged on the back side of a holder and covers an opening of the holder, an image sensor arranged on the back side of the optical member, and fixed to the holder. A holding member that holds the image sensor, a flexible substrate that is disposed on the back side of the holding member and is electrically connected to the image sensor, and a member that is disposed so as to surround the image sensor. And a second edge opposite to the holding member, wherein the first edge is the edge of the optical member, and the second edge is opposite to the edge of the optical member. An elastic member that is housed so as to surround the imaging device in a housing space that is provided by being arranged between the optical member and the holding member so that an edge of the image sensor is in contact with the holding member. Imaging characterized by comprising To provide a location.

  According to the present invention, the thickness in the optical axis direction can be suppressed, and entry of foreign matter such as dust and dirt into the imaging surface can be prevented without applying extra force to the imaging device.

1 is a perspective view illustrating an appearance of an imaging apparatus according to an embodiment of the present invention. It is a perspective view which shows the state by which the lens-barrel was extended | stretched in the imaging device of FIG. It is a disassembled perspective view which shows the holding structure of the image pick-up element provided in the digital camera of FIG. It is a longitudinal cross-sectional view which shows the holding structure of FIG. It is a disassembled perspective view which shows the holding structure of the conventional image pick-up element. It is a longitudinal cross-sectional view which shows the holding structure of the image pick-up element of FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a perspective view showing an external appearance of an imaging apparatus according to an embodiment of the present invention. FIG. 2 is a perspective view showing a state in which the lens barrel is extended in the imaging apparatus of FIG. In this embodiment, a digital camera will be described as an imaging device.

  As shown in FIGS. 1 and 2, the digital camera includes a box-shaped main body 19 having a small thickness (depth). A finder 24, auxiliary light emitting unit 23, strobe 25, and lens barrel 26 are provided on the front surface of the main body 19. Here, the auxiliary light emitting unit 23 emits auxiliary light when performing photometric distance measurement.

  A release button 20, a power switch button 22 and a zoom switch 21 are provided on the upper surface of the main body 19. In addition, a plurality of operation buttons (not shown) for switching functions, a liquid crystal display (not shown) for displaying captured images, and the like are provided on the back surface of the main body 19.

  Here, the lens barrel 26 is a retractable lens barrel, and is housed in the main body 19 as shown in FIG. 1 when the power of the digital camera is turned off. On the other hand, when the power is turned on, the lens barrel 26 is extended from the main body 19 as shown in FIG.

  Next, an image sensor holding structure provided in the digital camera will be described with reference to FIGS. FIG. 3 is an exploded perspective view showing a holding structure of the image sensor provided in the digital camera of FIG. 4 is a longitudinal sectional view showing the holding structure of FIG.

  The digital camera includes a CCD holder 1 as shown in FIGS. A mask member 2, a low-pass filter (optical member) 3, an image sensor protection member 5, an image sensor 6, a holding member 8, and a flexible printed circuit board (signal transmission member) 7 are incorporated in the CCD holder 1.

  Here, the CCD holder 1 is a holder whose opening is provided coaxially with the optical axis. A mask member 2 and a low-pass filter 3 are incorporated in the CCD holder 1 so as to be coaxial with the optical axis. The mask member 2 is a member for determining the amount of light incident on the image pickup surface of the image pickup device 6 from the back surface and blocking harmful light. The low-pass filter 3 is a filter for cutting light in a predetermined band, and is disposed on the back side of the mask member 2.

  The image sensor 6 is composed of a CCD, a CMOS, or the like. The imaging element 6 is fixed to the holding member 8 by an adhesive portion 6a made of an adhesive. The holding member 8 is attached to the CCD holder 1 with a plurality of screws 9 so that the image sensor 6 is coaxial with the low-pass filter 3 (so as to be coaxial with the optical axis). The flexible printed circuit board 7 is a board for transmitting and receiving signals to and from the image sensor 6 and is disposed on the back side of the holding member 8. The flexible printed board 7 is electrically connected to the image sensor 6 and is fixed to the holding member 8.

  The imaging element protection member 5 is made of an elastic member such as rubber, and has a frame shape formed so as to surround the imaging element 6. Specifically, the imaging element protection member 5 is formed in a frame shape having an inner edge facing the edge of the low-pass filter 3 and an outer edge extending in a skirt shape toward the holding member 8. The imaging element protection member 5 is disposed between the low-pass filter 3 and the holding member 8 so that the inner edge is in contact with the edge of the low-pass filter 3 and the outer edge is in contact with the holding member 8.

  Here, the inner edge portion of the image sensor protecting member 5 comes into contact with the edge portion of the low-pass filter 3 in a state of being elastically deformed in the thickness direction. That is, the inner edge portion of the image sensor protection member 5 is in close contact with the low-pass filter 3 in an elastically deformed state. Further, the image sensor protection member 5 presses the low-pass filter 3 together with the mask member 2 against the CCD holder 1. As a result, the low-pass filter 3 is held between the imaging element protection member and the CCD holder 1 together with the mask member 2.

  The outer edge of the image sensor protecting member 5 is pressed against the holding member 8 by a plurality of spring members (pressing members) 4 disposed between the CCD holder 1 and the holding member 8. Thereby, the outer edge part of the image pick-up element protection member 5 is closely_contact | adhered to the holding member 8 in the state elastically deformed.

  As described above, the imaging element protection member 5 cooperates with the low-pass filter 3 and the holding member 8 to form an accommodation space in which the imaging element 6 can be shut off from the outside. Therefore, the imaging surface of the imaging element 6 is externally provided. Intrusion of foreign matter such as dust and dust into the door is prevented. That is, foreign matter such as dust or dust is prevented from adhering to the image pickup surface of the image pickup device 6, and reflection of foreign matters that impair image quality can be eliminated.

  Further, since the image sensor protecting member 5 is disposed without applying a load to the bonding portion 6a between the image sensor 6 and the image sensor 6 holding member 8, an extra force is not applied to the image sensor 6 and the image sensor. There is no fear that the position of the image pickup surface 6 is shifted.

  In addition, since the imaging and protection member 5 has an inner edge portion that comes into contact with the edge portion of the low-pass filter 3, it is possible to suppress an increase in the interval between the low-pass filter 3 and the imaging element 6, and in the optical axis direction. An increase in thickness can be suppressed.

  Further, since the low-pass filter 3 is pressed against and held by the CCD holder 1 by the image sensor protection member 5, it is not necessary to fix it using other means such as adhesion. The holding can be simplified.

  In the present embodiment, the flexible printed circuit board 7 and the holding member 8 are individually configured, and the flexible printed circuit board 7 is disposed on the back surface side of the holding member 8. Instead of this, for example, the flexible printed circuit board 7 and the holding member 8 can be integrally formed. In this case, the imaging element protection member 5 is configured such that the outer edge portion thereof can contact at least one of the flexible printed circuit board 7 and the holding member 8. Further, for example, the flexible printed board 7 may be disposed between the imaging element 6 and the holding member 8 so that the flexible printed board 7 is held by the holding member 8. Also in this case, the imaging element protection member 5 is configured such that the outer edge portion thereof can contact at least one of the flexible printed circuit board 7 and the holding member 8.

1 CCD holder 3 Low-pass filter (optical member)
4 Spring member (pressing member)
5 Imaging element protection member (elastic member)
6 Imaging device 7 Flexible printed circuit board (flexible circuit board)
8 Holding members

Claims (4)

An optical member disposed on the back side of the holder and covering the opening of the holder;
An image sensor disposed on the back side of the optical member;
A holding member fixed to the holder and holding the image sensor;
A flexible substrate disposed on the back side of the holding member and electrically connected to the imaging element;
A member disposed so as to surround the imaging device, the first member having a first edge facing the edge of the optical member, and a second edge facing the holding member; In the accommodation space provided by arranging the edge between the optical member and the holding member so that the edge is in contact with the edge of the optical member and the second edge is in contact with the holding member, An imaging apparatus comprising: an elastic member that is housed so as to surround the imaging element.   The second edge portion of the imaging element protection member is pressed toward the holding member by at least one pressing member disposed between the imaging element protection member and the holder. The imaging device according to claim 1.   The imaging apparatus according to claim 1, wherein the imaging element protection member is elastically deformed between the optical member and the holding member and presses the optical member toward the holder.   4. The imaging apparatus according to claim 1, wherein the second edge portion of the imaging element protection member is in contact with at least one of the holding member and the flexible substrate. 5.

Images