JP2007241305A - Electronic still camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To miniaturize a camera body of an electronic still camera incorporating a shutter unit, by reducing dimensions in an optical path direction of the camera body. <P>SOLUTION: The shutter unit includes; a lens-side frame which has a first opening allowing photographic light to pass therethrough and is disposed on a photographic lens side of a shutter curtain; and an imaging unit-side frame which has a second opening allowing photographic light to pass therethrough and is disposed on an imaging unit side of the shutter curtain. With respect to the shutter curtain, a shutter blade having the longest extent of movement out of a plurality of shutter blades is disposed nearest to a photographic lens, and a shutter blade having the shortest extent of movement is disposed nearest to an imaging unit. The photographic lens side of the imaging unit projects into the second opening of the imaging unit-side frame of the shutter unit, and a projection end of the imaging unit is disposed nearer the imaging unit side than a shutter curtain-side opening end of the second opening. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an electronic still camera incorporating a shutter unit.

  An electronic still camera is a camera that photoelectrically converts photographing light from a subject using a solid-state imaging device and records a subject image as electronic data in a memory. Generally, a CCD (Charge Coupled Device) such as a frame transfer method or an interline transfer method is used as a solid-state imaging device of an electronic still camera.

  In such an electronic still camera using a CCD, a mechanical shutter is often disposed on the photographing lens side of the CCD, and this shutter prevents extra light from entering the CCD other than the exposure time. For this reason, it is possible to prevent noise components such as smear from entering the signal charges accumulated and sequentially transferred in the light receiving portion of the CCD.

  In some models of this type of electronic still camera, the charge accumulation time of the light receiving unit is controlled by the control circuit in the CCD with the mechanical shutter opened, and the exposure time is determined. Further, in some models having high functions, the exposure time is determined by controlling the time during which the shutter is opened by a mechanical shutter that can be opened and closed at high speed.

  8 and 9 show an example of an electronic still camera incorporating such a mechanical shutter. In the figure, a lens mount 3 is disposed at a front portion 1 a of the camera body 1. A photographing lens 5 is attached to the front portion 1 a of the camera body 1 via a lens mount 3.

  In the camera body 1, a movable mirror 9 is disposed on the optical path 7 a of the photographing light 7 that has passed through the photographing lens 5. A finder screen 11 that forms an image of the photographing light 7 is disposed on the reflection light path 7 b of the photographing light 7 reflected by the mirror 9. On the opposite side of the finder screen 11 from the mirror 9, a pentaprism 13 and an eyepiece 15 are arranged.

  A shutter unit 17 is disposed on the back surface side of the mirror 9 on the optical path 7 a of the photographing light 7 in the camera body 1, and is fixed to a frame 19 disposed in the camera body 1.

  The shutter unit 17 is provided with a shutter curtain 21 that opens and closes the optical path 7 a of the photographing light 7. An imaging unit 23 is arranged on the opposite side of the shutter unit 17 from the mirror 9. The imaging unit 23 is equipped with a solid-state imaging device 25 made of a CCD or the like. A cover glass 27 for protecting the solid-state imaging device 25 is fixed on the shutter unit 17 side of the imaging unit 23.

In the imaging unit 23, an aluminum substrate 31 for supporting the solid-state imaging device 25 on the frame 19 is disposed on the back cover 29 side of the camera body 1. A flexible substrate 33 connected to the solid-state imaging device 25 is disposed on the back cover 29 side of the aluminum substrate 31. A leaf spring member 35 is attached to the back cover 29 of the camera body 1 toward the inside of the camera body 1. Then, the aluminum substrate 31 is pressed against the frame 19 by the leaf spring member 35 and the solid-state imaging device 25 is placed at a predetermined position in the camera body 1 so that the photographing light 7 forms an image on the light receiving surface. It is fixed.
JP-A-2-308231

  However, in such a conventional electronic still camera, the shutter curtain 21 collides with the cover glass 27 of the imaging unit 23 when the shutter curtain 21 is bent in the direction of the optical path 7a due to an impact when the shutter curtain 21 is closed. In order to prevent the cover glass 27 from being damaged, the distance between the shutter unit 17 and the imaging unit 23 must be determined in consideration of the maximum amount of deflection of the shutter curtain 21 in addition to the dimensional error of the parts. There was a problem of not becoming. For this reason, there is a problem that the size of the camera body 1 in the direction of the optical path 7a increases, which hinders downsizing of the camera body 1.

  The present invention has been made to solve such a conventional problem, and an object thereof is to provide an electronic still camera capable of reducing the size of the camera body in the optical path direction and miniaturizing the camera body. .

  An electronic still camera of the present invention includes a photographic lens that guides photographic light into the camera body, an imaging unit that is disposed on the optical path of the photographic light, and includes a solid-state imaging device that receives the photographic light and generates an image signal; A shutter unit that is disposed between the photographing lens and the solid-state imaging device and includes a shutter curtain that is configured to include a plurality of shutter blades that slide in a direction perpendicular to the optical path of the photographing light and that can be opened and closed. In the electronic still camera, the shutter unit has a first opening that allows photographing light to pass therethrough, a lens-side frame that is disposed on the photographing lens side of the shutter curtain, and a second opening that allows the photographing light to pass therethrough. An imaging unit-side frame disposed on the imaging unit side of the shutter curtain, and the shutter curtain has a plurality of shutters. -Among the blades, the shutter blade having the largest movement amount is disposed on the photographing lens side, and the shutter blade having the smallest movement amount is disposed on the imaging unit side, and the photographing lens side of the imaging unit Projecting into the second opening of the imaging unit side frame of the shutter unit, and the projecting end of the imaging unit is disposed closer to the imaging unit than the frame surface on the shutter curtain side of the imaging unit side frame, and the shutter The membrane is characterized in that it can be opened and closed.

  In the electronic still camera of the present invention, the imaging unit includes a filter on the photographing lens side of the solid-state imaging device.

  In the electronic still camera of the present invention, the imaging lens side of the imaging unit is in contact with the shutter unit in a pressed state.

  In the electronic still camera of the present invention, since the photographing lens side of the imaging unit arranged in the camera body protrudes into the shutter unit, the length of the photographing lens of the camera body in the optical path direction can be reduced. The camera body can be formed smaller than the conventional one. In addition, the shutter curtain consisting of a plurality of shutter blades is located in the shutter unit, with the shutter blade that has the greatest amount of movement and is bent the most when the shutter curtain closes. When the shutter curtain is driven at a high speed and the shutter unit is configured to have a relatively large impact when the shutter curtain closes, it is possible to prevent the bent shutter blades from contacting the imaging unit. It is possible to prevent the light receiving portion such as the cover glass of the imaging unit from being damaged.

  In the electronic still camera of the present invention, the imaging unit having a filter on the photographic lens side is disposed so as to protrude into the shutter unit. Therefore, the camera body can be made smaller than the conventional one.

  In the electronic still camera of the present invention, since the photographing lens side of the imaging unit is in contact with the shutter unit in a pressed state, the imaging unit and the shutter unit can be arranged with high dimensional accuracy. It can be placed closer to the curtain.

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

  1 and 2 show a first embodiment of the electronic still camera of the present invention. In the figure, for example, a lens mount 43 is disposed at a front portion 41a of a single-lens reflex type camera body 41 with interchangeable lenses. A photographing lens 45 is attached to the front portion 41 a of the camera body 41 via a lens mount 43.

  In the camera body 41, a movable mirror 49 is arranged on an optical path 47a of the photographing light 47 that has passed through the photographing lens 45. A finder screen 51 for forming an image of the photographing light 47 is disposed on the reflection light path 47 b of the photographing light 47 reflected by the mirror 49. On the opposite side of the finder screen 51 from the mirror 49, a pentaprism 53 and an eyepiece lens 55 are arranged.

  A shutter unit 57 is disposed on the back side of the mirror 49 on the optical path 47 a of the photographing light 47 in the camera body 41. The shutter unit 57 is fixed to a frame 59 disposed in the camera body 41 by a screw member 58.

  As shown in FIG. 2, a lens side frame 61 is disposed on the side of the photographing lens 45 of the shutter unit 57. The lens side frame 61 is formed with a first opening 61a for allowing the photographing light 47 to pass therethrough. An imaging unit side frame 63 is arranged on the opposite side of the shutter unit 57 from the photographing lens 45. The imaging unit side frame 63 is formed with a second opening 63 a for allowing the imaging light 47 to pass therethrough.

  In the shutter unit 57, a shutter curtain 65 that opens and closes the optical path 47 a of the photographing light 47 is disposed between the lens side frame 61 and the imaging unit side frame 63. The shutter curtain 65 is composed of a plurality of shutter blades 67a, 67b, 67c, 67d, and 67e that slide in a direction perpendicular to the optical path 47a of the photographing light 47. The shutter curtain 65 is arranged with the shutter blade 67a having a large moving amount facing the photographing lens 45 side. On both surfaces of the shutter curtain 65, a front restriction plate 69 and a rear restriction plate 71 having openings having the same size as the first and second openings 61a and 63a are arranged. When the shutter curtain 65 is driven by the front restriction plate 69 and the rear restriction plate 71, the shutter blades 67a to 67e do not directly contact the lens side frame 61 and the imaging unit side frame 63, and the shutter blades 67a to 67a. 67e is prevented from being damaged.

  On the opposite side of the shutter unit 57 from the photographic lens 45, the imaging unit 73 is disposed so that one end on the photographic lens 45 side protrudes into the second opening 63 a of the imaging unit side frame 63. In the imaging unit 73, for example, a solid-state imaging device 75 made of a CCD or the like is mounted. A cover glass 77 for protecting the solid-state imaging device 75 is fixed on the shutter unit 57 side of the imaging unit 73.

  On the back surface 73a side of the imaging unit 73, a flexible substrate 79 connected to the solid-state imaging device 75 is disposed. The back surface 73 a side of the imaging unit 73 is fixed to an imaging unit holder 81 that supports the imaging unit 73 in the camera body 41. The imaging unit holder 81 is fixed to the frame 59 together with the imaging unit 73 by a screw member 83.

  In the above-described electronic still camera, when shooting is started, that is, when the shutter is released, the shutter curtain 65 is opened, and charge accumulation in the light receiving portion of the solid-state image sensor 75 is started. Further, with the shutter curtain 65 opened, the charge accumulation time of the light receiving portion of the solid-state image sensor 75 is controlled by the control circuit in the solid-state image sensor 75, and the exposure time is determined by this control.

  The shutter curtain 65 is closed to shield the solid-state image sensor 75 after the exposure time is controlled by the control circuit. Due to the impact when the shutter curtain 65 is closed, the shutter blades 67a to 67e bend toward the optical path direction. At this time, the shutter blade 67a that has the largest movement amount and is bent most greatly is located on the photographing lens 45 side, so that the bent shutter blades 67a to 67e are prevented from contacting the imaging unit 73. For this reason, the light receiving portion such as the cover glass 77 of the imaging unit 73 is prevented from being damaged by the contact.

  In the electronic still camera configured as described above, the photographing lens 45 side of the imaging unit 73 disposed in the camera body 41 is disposed so as to protrude into the shutter unit 57, and therefore the optical path of the photographing lens 45 of the camera body 41. The length in the 47a direction can be reduced, and the camera body 41 can be formed smaller than the conventional one.

  Further, the shutter curtain 65 composed of a plurality of shutter blades 67a to 67e is located on the photographing lens 45 side, and the shutter blade 67a that has the largest moving amount and is bent most when the shutter curtain 65 is closed, is a shutter unit. Since the shutter curtain 65 is driven at a high speed and the shutter unit 57 is configured to have a relatively large impact when the shutter curtain 65 is closed, the bent shutter blades 67a to 67e capture images. The contact with the unit 73 can be prevented, and the light receiving portion such as the cover glass 77 of the imaging unit 73 can be prevented from being damaged by the contact.

  FIG. 3 shows a second embodiment of the electronic still camera of the present invention. In this embodiment, on the cover glass 77 of the imaging unit 73, for example, a filter 85 that removes a high-frequency component of photographing light that causes noise is adhered. The photographic lens 45 side of the filter 85 is disposed so as to protrude into the second opening 63 a of the imaging unit side frame 63 of the shutter unit 57.

  Even with the electronic still camera of this embodiment, the same effects as those of the first embodiment described above can be obtained. However, in this embodiment, an imaging unit 73 having a filter 85 on the photographing lens 45 side is provided in the shutter unit 57. In particular, the length in the direction of the optical path 47a of the photographic lens 45 of the camera body 41 having the filter 85 for removing noise components and the like can be reduced, and the camera body 41 can be made smaller than the conventional one. can do.

  FIG. 4 shows a third embodiment of the electronic still camera of the present invention. In this embodiment, the shutter unit 57 is tilted so that the distance between the shutter blades 67a to 67e and the imaging unit 73 is equal in a state where the shutter curtain 65 is closed. In the electronic still camera of this embodiment, when the shutter blades 67a to 67e of the shutter curtain 65 are closed, the shutter unit 57 is placed in the camera body 41 so that the distance between the shutter blades 67a to 67e and the imaging unit 73 is equal. In particular, when the shutter unit 65 is driven at a relatively low speed, the impact when the shutter curtain 65 closes is small, and the shutter unit 57 is configured to be less bent, The shutter unit 57 and the imaging unit 73 can be disposed close to each other.

  5 and 6 show a fourth embodiment of the electronic still camera of the present invention. In this embodiment, the first opening 61a of the lens side frame 61 of the shutter unit 57 is formed smaller than the second opening 63a of the imaging unit side frame 63 and the cross section of the imaging unit 73 on the shutter unit 57 side. Yes. The shutter curtain 65, the front restriction plate 69, and the rear restriction plate 71 are formed in a size corresponding to the first opening 61a of the lens side frame 61.

  In the electronic still camera of this embodiment, the first opening 61a of the lens side frame 61 is formed to be smaller than the cross section of the image pickup unit 73 on the shutter unit 57 side, and has a size corresponding to the first opening 61a. Since the shutter curtain 65 is formed, the shutter curtain 65 can be formed smaller than the conventional one. For this reason, the impact when the shutter curtain 65 is closed can be reduced, and the deflection of the shutter curtain 65 is minimized. Therefore, the imaging unit 73 is disposed at a position close to the shutter curtain 65 of the shutter unit 57. Can do.

  Further, since the second opening 63a of the imaging unit side frame 63 disposed on the imaging unit 73 side of the shutter curtain 65 is formed larger than the first opening 61a of the lens side frame 61, the first opening 61a can be formed small without depending on the size of the second opening 63a, and the shutter curtain 65 can be formed small.

  FIG. 7 shows a fifth embodiment of the electronic still camera of the present invention. In this embodiment, a stepped portion 73b is formed around the shutter unit 57 side of the imaging unit 73, and this stepped portion 73b is formed on the inner periphery of the second opening 63a of the imaging unit side frame 63 of the shutter unit 57. It is in contact. A plate spring member 87 is disposed on the image pickup unit 73 side of the image pickup unit holder 81, and the image pickup unit 73 is brought into contact with the image pickup unit side frame 63 in a pressed state by the plate spring member 87.

  In the electronic still camera of this embodiment, since the shutter unit 57 side of the imaging unit 73 is in contact with the shutter unit 57 in a pressed state, the imaging unit 73 and the shutter unit 57 can be arranged with high dimensional accuracy. The imaging unit 73 can be disposed at a position closer to the shutter curtain 65.

  In the above-described embodiment, the example in which the present invention is applied to the single-lens reflex type camera body 41 in which the lens can be replaced has been described. However, the present invention is not limited to such an embodiment. The present invention may be applied to a type of electronic still camera.

  In the above-described embodiment, an example in which the shutter curtain 65 is configured by a plurality of shutter blades 67a to 67e has been described. However, the present invention is not limited to such an embodiment. You may comprise by the front curtain and rear curtain which each have several shutter blades.

  The present invention is applicable to an electronic still camera with a built-in shutter unit.

It is sectional drawing which shows 1st Embodiment of the electronic still camera of this invention. It is sectional drawing which shows the detail of the principal part of FIG. It is sectional drawing which shows 2nd Embodiment of the electronic still camera of this invention. It is sectional drawing which shows 3rd Embodiment of the electronic still camera of this invention. It is sectional drawing which shows 4th Embodiment of the electronic still camera of this invention. It is a front view which shows the state which looked at FIG. 5 from the back of the camera main body. It is sectional drawing which shows 5th Embodiment of the electronic still camera of this invention. It is sectional drawing which shows the conventional electronic still camera. It is sectional drawing which shows the detail of the principal part of FIG.

Explanation of symbols

41 Camera body 45 Shooting lens 47 Shooting light 47a Optical path 57 Shutter unit 61 Lens side frame 61a First opening 63 Imaging unit side frame 63a Second opening 65 Shutter curtain 67a, 67b, 67c, 67d, 67e Shutter blade 73 Imaging unit 75 Solid-state image sensor 85 Filter

Claims (3)

A photographic lens that guides the photographic light into the camera body;
An imaging unit including a solid-state imaging device that is disposed on an optical path of the imaging light and that receives the imaging light and generates an image signal;
A shutter unit that is disposed between the photographing lens and the solid-state image sensor and incorporates a shutter curtain composed of a plurality of shutter blades that slide in a direction perpendicular to the optical path of the photographing light;
In an electronic still camera having
The shutter unit has a first opening for allowing photographing light to pass, a lens-side frame disposed on the photographing lens side of the shutter curtain, and a second opening for allowing photographing light to pass. An imaging unit side frame disposed on the imaging unit side of the curtain,
In the shutter curtain, among the plurality of shutter blades, the shutter blade having the largest movement amount is disposed on the photographing lens side, and the shutter blade having the smallest movement amount is disposed on the imaging unit side,
The imaging lens side of the imaging unit protrudes into the second opening of the imaging unit side frame of the shutter unit, and the protruding end of the imaging unit is from the opening end of the second opening on the shutter curtain side. Placed on the imaging unit side,
The electronic still camera, wherein the shutter film is held openably and closably. The electronic still camera according to claim 1.
The electronic still camera, wherein the imaging unit has a filter on the photographing lens side of the solid-state imaging device. The electronic still camera according to claim 1 or 2,
An electronic still camera, wherein the imaging lens side of the imaging unit is in contact with the shutter unit in a pressed state.

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