JP2008197323A - Optical apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide optical apparatus capable of correcting image blur of an image formed in an eyepiece optical system. <P>SOLUTION: The optical apparatus (1) includes: a reflection part (33) reflecting image light passing through a lens barrel (2) and guiding it to the eyepiece optical system (10); a first drive part (35) driving the reflection part relative to the eyepiece optical system; and a control part (50) controlling the first drive part in accordance with output from a blur detection part (40) so as to correct the image blur of the image formed in the eyepiece optical system. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

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

As a camera having an image blur correction function, for example, a camera that shifts an image sensor in a plane perpendicular to the optical axis is known (see, for example, Patent Document 1).
JP 2006-174226 A

Conventionally, when this type of blur correction apparatus is applied to a single-lens reflex camera, an image formed in the optical finder has not had an image blur correction effect.
An object of the present invention is to provide an optical apparatus that can correct image blurring of an image formed in an eyepiece optical system.

The present invention solves the above problems by the following means. In addition, in order to make an understanding easy, although the code | symbol corresponding to embodiment of this invention is attached | subjected and demonstrated, it is not limited to this.
According to the first aspect of the present invention, the reflecting portion (33) that reflects the image light that has passed through the lens barrel (2) and guides it to the eyepiece optical system (10), and the reflecting portion is driven with respect to the eyepiece optical system. A first drive unit (35) and a control unit that controls the first drive unit according to the output of the blur detection unit (40) to correct image blur of an image formed in the eyepiece optical system ( 50).

According to a second aspect of the present invention, in the optical device according to the first aspect, the control unit (50) is configured to provide the reflection unit (50) with respect to the optical axis (Z) of the image light incident on the reflection unit (33). The optical apparatus (1) is characterized in that image blur correction is performed by tilting the reflection surface (33a) of (33).
According to a third aspect of the present invention, there is provided the optical apparatus according to the first or second aspect, wherein the reflecting portion (33) guides the image light to the eyepiece optical system (10), and the image. A second drive unit (34) for driving light to a second position for guiding light to the imaging unit (20); and the control unit (50) at the first position and the second position An optical apparatus (1) that performs the image blur correction.
According to a fourth aspect of the present invention, in the optical device according to the third aspect, the imaging unit (20) is provided on the opposite side of the eyepiece optical system (10) with the reflection unit (33) interposed therebetween. It is an optical instrument characterized by.
Invention of Claim 5 is provided with the support part (31) which supports the said reflection part (33) in the optical instrument of any one of Claim 1- Claim 4, The said support part is the said The first drive unit (35) is provided so as to be rotatable about an axis (C) orthogonal to the optical axis (Z) of the image light incident on the reflection unit. The optical device (1) is characterized by being driven.
According to a sixth aspect of the present invention, in the optical instrument according to the fifth aspect, the axis (C) orthogonal to the optical axis (Z) of the image light includes a reflecting surface (33a) of the reflecting portion (33). An optical apparatus (1) characterized by being arranged above.
Note that the configuration described with reference numerals may be modified as appropriate, and at least a part of the configuration may be replaced with another component.

  ADVANTAGE OF THE INVENTION According to this invention, the optical apparatus which can correct | amend image blurring of the image imaged in an eyepiece optical system can be provided.

Hereinafter, the present invention will be described in more detail with reference to the drawings and the like. In the following embodiments, a camera system will be described as an example of an optical device.
FIG. 1 is a schematic diagram illustrating a configuration of a camera system according to an embodiment.

The camera system 1 is a lens interchangeable single-lens reflex digital camera system in which a lens barrel 2 is detachably attached to a camera body 3.
The lens barrel 2 includes an imaging optical system constituted by a lens group (not shown). Hereinafter, a description will be given with the symbol Z attached to the optical axis of the imaging optical system included in the lens barrel 2.

The camera body 3 is formed in a box shape from, for example, a metal material or a synthetic resin material, and includes a space portion inside. In the camera body 3, the lens barrel 2 is mounted on the front portion, and the back portion, which is the surface portion on the opposite side of the front portion, faces the photographer at the normal photographing position. Here, in this specification, the normal shooting position refers to the posture of the camera body 3 when shooting a horizontally long image with the optical axis Z substantially horizontal.
Hereinafter, the arrangement of the camera body 3 and the elements included in the camera body 3 will be described with reference to the normal shooting position. In addition, as shown in the figure, two axes orthogonal to the optical axis Z are denoted by symbols X and Y for explanation. Here, the X-axis extends in the horizontal direction, and the Y-axis extends in the vertical direction. The intersection (the origin of the coordinate system) of these X axis, Y axis, and Z axis is set on a reflection surface 33a of a mirror 33 described later.

The camera body 3 includes a finder optical system 10, an image sensor 20, a mirror unit 30, an angular velocity sensor 40, and a control unit 50.
The finder optical system 10 is provided on the upper surface of the camera body 3 and includes a pentaprism 11, an eyepiece 12, and a focusing screen 13.
The pentaprism 11 is an optical element that guides the object image formed on a focusing screen 13 provided between the pentaprism 11 and a mirror unit 30 described later to an eyepiece 12 as a formed image.
The eyepiece unit 12 includes an eyepiece lens (not shown) so that the photographer can enlarge and observe the subject image formed on the focusing screen 13.
The focusing screen 13 is a portion on which the image light reflected by the mirror unit 30 is imaged.

  The imaging element 20 is a photoelectric conversion element that converts image light reflected by the mirror unit 30 into an electrical signal. The imaging element 20 is disposed inside the camera body 3 and on the opposite side of the finder optical system 10 (near the bottom surface of the camera body 3) with the mirror unit 30 interposed therebetween, with the imaging surface thereof being substantially horizontal. Yes. For the image sensor 20, a CCD, a CMOS, or the like can be used. Further, a silver salt film may be used in place of the image sensor 20.

The mirror unit 30 is disposed on the optical axis Z between the finder optical system 10 and the image sensor 20. The mirror unit 30 reflects the optical path of the image light that has passed through the lens barrel 2 and guides the image light to the finder optical system 10 or the image sensor 20.
2 is a view showing a mirror unit provided in the camera body of the camera system shown in FIG. 1, wherein (a) is a perspective view, and (b) is a view taken along the line bb of (a). Each is shown.
The mirror unit 30 includes a support portion 31, a rotating shaft 32, a mirror 33, a mirror switching actuator 34 (see FIG. 1), an image blur correction actuator 35 (35x, 35y), and a connection rubber 36.
The support portion 31 is a plate-like member whose planar shape is substantially rectangular, and functions as a base of the mirror unit 30. The support portion 31 is arranged in a state in which the longitudinal direction is substantially parallel to the X axis (substantially horizontal direction). The support portion 31 includes a recess formed by recessing an intermediate portion in the X-axis direction on the surface portion facing the mirror 33, and has a substantially U-shaped cross section (FIG. 2 ( b)).

A pair of rotary shafts 32 are provided so as to protrude from both ends of the support portion 31 in the X-axis direction (longitudinal direction). The rotation shaft 32 is supported by a bearing (not shown), and the support portion 31 is rotatable around the central axis C of the rotation shaft 32. The central axis C is arranged coaxially with the X axis, and is arranged on a plane including a reflection surface 33a of a mirror 33 described later (see FIG. 2B).
The mirror 33 reflects the image light acquired by the lens barrel 2 as described above, and its planar shape is substantially rectangular. The mirror 33 is disposed so as to be substantially parallel to the support portion 31 and is mounted in the recess of the support portion 31.

The mirror unit 30 is an observation position where the reflection surface 33a of the mirror 33 is inclined 45 ° with respect to the optical axis Z and directed obliquely upward, and the image light that has passed through the lens barrel 2 is reflected to the finder optical system 10. (See FIGS. 3 (a) and 3 (b)), and rotated from the observation position around the rotation axis 32 by, for example, 90 °, and the reflection surface of the mirror 33 is directed obliquely downward and passed through the lens barrel 2. It can be moved between a photographing position where the image light is reflected by the image sensor 20 (see FIGS. 3C and 3D).
The mirror switching actuator 34 is an electromagnetic actuator that drives the mirror unit between the observation position and the imaging position described above.

The image blur correction actuator 35 drives the mirror 33 with respect to the support portion 31 to tilt the reflection surface of the mirror 33. The image blur correction actuator 35 is disposed between the support portion 31 and the mirror 33.
Here, the camera system 1 corrects the image blur caused by the change in the posture of the camera body 3 around the X axis and the Y axis. The change in posture around the X axis is called pitching, and the change in posture around the Y axis is called yawing.
The image blur correcting actuator 35 includes, for example, a known laminated piezoelectric element, and is displaced (expanded / contracted) in the thickness direction, that is, the direction in which the support portion 31 and the mirror 33 are moved closer to or away from each other when a voltage is applied. To do.

The image blur correction actuator 35 includes an X-side actuator 35x and a Y-side actuator 35y.
The X-side actuator 35x tilts the mirror 33 with respect to the central axis C with the center of the reflecting surface 33a (the point where the optical axis Z and the central axis C intersect) as a fulcrum, thereby correcting image blur in the yawing direction. Is what you do. The X-side actuator 35x is disposed on an axis parallel to the central axis C.
The Y-side actuator 35y tilts the mirror 33 with respect to an axis perpendicular to the central axis C with the center of the reflecting surface 33a as a fulcrum, thereby performing image blur correction in the pitching direction. The Y-side actuator 35y is disposed on an axis that passes through the center of the reflecting surface 33a of the mirror 33 and is parallel to an axis that is orthogonal to the center axis C. The Y-side actuator 35y is disposed in a region closer to the image sensor 20 than the central axis.

The connection rubber 36 connects the mirror 33 and the support portion 31, and is disposed between the support portion 31 and the mirror 33. The connection rubber 36 is made of a rubber material that can be elastically deformed.
The connection rubber 36 is bonded to the center of the back surface of the mirror 33 (the surface on the side opposite to the reflection surface 33a) and the support portion 31 with an adhesive, for example. As a result, when the mirror 33 is driven by the image blur correction actuator 35, the center of the reflection surface 33a is not substantially moved.

The angular velocity sensor 40 (see FIG. 1) detects a change in posture of the camera body 3, and includes, for example, a known gyro sensor. The angular velocity sensor 40 includes two sensors, a sensor that detects an angular velocity around the Y axis (the yawing direction) and a sensor that detects an angular velocity around the X axis (the pitching direction).
The control unit 50 calculates the driving direction and driving amount of the mirror 33 according to the output of the angular velocity sensor 40, and controls the image blur correction actuator 35 according to the calculation result, thereby connecting to the focusing screen 13 or the image sensor 20. This is a portion for correcting image blur of an image to be imaged.

Next, the operation of the camera system 1 when taking an image will be described.
FIG. 3 is a diagram showing the camera system 1 at the observation position and the photographing position.
In FIG. 3, (a) and (b) each show a state in which the mirror unit 30 is at the observation position. (C) shows a state in which the mirror unit 30 has moved from the observation position shown in (a) to the photographing position, and (d) shows that the mirror unit 30 has moved from the observation position shown in (b) to the photographing position. Indicates the state.
At the time of framing, the mirror unit 30 is at the observation position shown in FIGS. 3A and 3B, and the image light that has passed through the lens barrel 2 is refracted upward in the vertical direction and guided to the finder optical system 10. It is burned. Thus, the photographer can observe the subject image formed on the focusing screen 13 through the eyepiece 12.
Here, during the framing, for example, when the posture of the camera body 3 changes due to camera shake or the like of the photographer, the control unit 50 moves in a direction to cancel the image blur of the subject image formed on the focusing screen 13. The mirror 33 is driven.
Hereinafter, this image blur correction operation will be described in detail.

When the posture of the camera body 3 changes due to camera shake or the like, the angular velocity sensor 40 detects this and outputs it to the control unit 50.
The controller 50 drives the image blur correction actuator 35 according to the output of the angular velocity sensor 40, changes the optical path of the image light (reflected light) reflected by the mirror 33, and thereby corrects the image blur of the subject image. It is supposed to be. In FIG. 3, among the optical axes of the image light reflected by the mirror 33, an alternate long and short dash line indicates the optical axis of the image light before the image blur correction, and a solid line indicates the optical axis of the image light after the image blur correction. ing.

For example, when a camera shake that causes the camera body 3 to rotate around the X axis (a camera shake in the pitching direction) occurs, the control unit 50 drives the Y-side actuator 35y to light the reflection surface 33a of the mirror 33. The angle with respect to the axis Z is changed (see FIGS. 3A and 3B).
3A shows a case where the posture of the camera body 3 changes so that the end of the lens barrel 2 on the subject side in the optical axis direction faces downward, and FIG. 3B shows the case of the lens barrel 2. The case where the attitude | position of the camera main body 3 changed so that the edge part by the side of a to-be-illuminated direction may face upward is shown. In the case of FIG. 3A, the Y-side actuator 35y is displaced in the extending direction, and in the case of FIG. 3B, the Y-side actuator 35y is displaced in the contracting direction.
For example, when camera shake (camera shake in the yawing direction) occurs so that the camera body 3 rotates around the Y axis, the control unit 50 drives the X-side actuator 35x (not shown). When the angular velocities around the X axis and the Y axis are detected, the control unit 50 drives the Y-side actuator 35y and the X-side actuator 35x, thereby correcting image blur.
The image blur correction control described above may be performed at all times during framing, and only when a release switch (not shown) provided in the camera body 3 is operated so as to be half-pressed. Also good.

In the camera system 1, when the release switch is fully pressed, the mirror unit 30 is driven from the observation position to the photographing position by the mirror switching actuator 34, whereby the subject image light is exposed to the image sensor 20.
Here, when the mirror unit 30 moves (rotates) from the observation position to the imaging position, the control unit 50 maintains the tilt angle of the mirror 33 at the observation position with respect to the support unit 31. That is, the mirror 33 and the support portion 31 rotate around the rotation shaft 32 with the same positional relationship as the image blur correction state during framing shown in FIG. 3A (see FIGS. 3C and 3D).
If it demonstrates using FIG. 3, if a release switch is fully pressed from the observation position shown to Fig.3 (a), it will move to the imaging | photography position shown in FIG.3 (c). When the release switch is fully pressed from the observation position shown in FIG. 3B, the camera moves to the photographing position shown in FIG. Thereby, the image blur of the subject image exposed by the image sensor 20 is corrected.
Note that since the subject image formed on the image sensor 20 is horizontally reversed, it is desirable that the image data generated based on the output of the image sensor 20 be electrically reversed horizontally and output.

Next, the effect of the camera system 1 of the present embodiment will be described in comparison with a camera including another image blur correction device.
As a known image blur correction apparatus for a camera, a lens driving type, an imaging unit driving type, and an image synthesis type are known (all are not shown).
A lens-driven blur correction device, for example, drives a part of a lens group provided in a lens barrel in a plane perpendicular to the optical axis, thereby correcting image blur of an image formed on an image sensor. To do. However, in this lens-driven blur correction device, an image blur correction effect cannot be obtained unless a lens barrel equipped with the blur correction device is attached to the camera body.

The imaging unit driving type blur correction device, for example, corrects image blur by driving an imaging unit including an imaging element in a plane perpendicular to the optical axis. In this case, an image blur correction effect can be obtained regardless of the type of the lens barrel, but the mirror that guides the image light to the finder optical system is provided on the subject side of the imaging unit, so that the image is formed in the finder optical system. Cannot correct the image blur.
An image composition type blur correction device, for example, captures a plurality of images in succession and combines these images to correct image blur. Depending on the image quality, the image quality may deteriorate.

On the other hand, the image blur correction control by the camera system of the present embodiment drives the mirror 33 provided in the camera body 3, so that an image blur correction effect can be obtained regardless of the type of the lens barrel 2.
Further, since the image formed on the focusing screen 13 of the finder optical system 10 is reflected by the mirror 33, image blurring of the image formed on the focusing screen 13 during framing can be corrected. Furthermore, the continuous shooting performance does not deteriorate and the image quality does not deteriorate.

[Deformation]
The present invention is not limited to the embodiments described above, and various modifications and changes are possible, and these are also within the technical scope of the present invention.
(1) The configuration of the optical apparatus to which the present invention is applied is not limited to that described in the embodiment, and can be changed as appropriate. For example, in the embodiment, the image light is refracted by the mirror. However, the present invention is not limited to this. For example, the image light may be refracted by a prism.
(2) In the embodiment, the image blur correction actuator that drives the mirror is a piezoelectric element, but the first drive unit that drives the mirror is not limited to this, and for example, a voice coil motor, a stepping motor, or the like. But you can.
(3) In the embodiment, the mirror is tilted to change the optical path of the reflected light. However, the present invention is not limited to this. For example, the mirror is moved (slided) in the optical axis direction (Z-axis direction) or the vertical direction (Y-axis direction). You may let them. In this case, only image blur around the X axis (pitching direction) can be corrected, which is useful when intentionally limiting horizontal blur correction control when performing so-called panning. In this case, in order to perform normal image blur correction, image blur around the Y axis (the yawing direction) may be corrected, for example, by shifting the image sensor.
(4) The embodiment has been described by taking a digital camera that captures a still image as an example of the optical device. However, the optical device is not limited thereto, and may be a movie camera that captures a moving image, for example. Further, it may be a telescope or a microscope without an imaging unit.

It is the schematic which shows the structure of the camera system of embodiment. It is a figure which shows the mirror unit with which the camera system of FIG. 1 was equipped. It is a figure which shows the operation | movement at the time of imaging | photography of the camera system of FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Camera system: 2 Lens barrel: 3 Camera body: 10 Finder optical system: 20 Image pick-up element: 30 Mirror unit: 31 Support part: 32 Rotating shaft: 33 Mirror: 34 Mirror switching actuator: 35 Image blur correction actuator: 40 angular velocity sensor: 50 control unit

Claims (6)

A reflection unit that reflects image light that has passed through the lens barrel and guides it to the eyepiece optical system;
A first driving unit that drives the reflecting unit with respect to the eyepiece optical system;
An optical apparatus comprising: a control unit that controls the first driving unit according to an output of a blur detection unit to correct image blur of an image formed in the eyepiece optical system. The optical instrument according to claim 1,
The optical device, wherein the control unit performs image blur correction by tilting a reflection surface of the reflection unit with respect to an optical axis of the image light incident on the reflection unit. The optical apparatus according to claim 1 or 2,
A second driving unit that drives the reflecting unit between a first position for guiding the image light to the eyepiece optical system and a second position for guiding the image light to the imaging unit;
The optical device, wherein the control unit performs the image blur correction at the first position and the second position. The optical apparatus according to claim 3.
The optical apparatus, wherein the imaging unit is provided on the opposite side of the eyepiece optical system with the reflection unit interposed therebetween. In the optical instrument according to any one of claims 1 to 4,
A support portion for supporting the reflection portion;
The support part is provided to be rotatable around an axis perpendicular to the optical axis of the image light incident on the reflection part,
The first drive unit drives the reflection unit with respect to the support unit. The optical apparatus according to claim 5, wherein
An optical device characterized in that an axis perpendicular to the optical axis of the image light is arranged on a plane including a reflection surface of the reflection portion.

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