JPH10170972A - Optical axis angle detecting device, optical axis angle varying device, and shake correction device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately detect the transmission optical axis angle of an optical system even when disturbance or an unknown element exists ahead of the driving means of an optical element or even when the change with time or the deterioration of the durability of the driving means occurs. SOLUTION: Detecting light outputted from a point light source 214 is projected to the optical acid angle varying optical systems (lenses 211(P) and 211(Y)) after it is changed to parallel beams by a collimator lens 215. The detecting light which irradiates the optical axis angle varying optical system is converged by an image-formation lens 216 after it is diffracted in accordance with the turning angle of the lenses 211(P) and 211(Y) by the optical axis angle optical system. the converged light is received by a light receiving position detector 217, and the light receiving position is detected.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image stabilizing device suitable for a camera image stabilizing device provided in, for example, a camera-integrated video tape recorder (hereinafter referred to as "video camera"). The present invention also relates to an optical axis angle variable device suitable for realizing the shake correction device. Further, the present invention relates to an optical axis angle detection device suitable for realizing the optical axis angle variable device.

[0002]

2. Description of the Related Art Generally, a video camera is provided with a camera shake correction device. Here, the camera shake correction device is a device for suppressing a shake of a captured image due to a camera shake of a video camera.

[0003] As the image stabilizing device, an optical image stabilizing device and an electric image stabilizing device are conventionally known. Of these, the optical image stabilization device can obtain high image quality and high correction accuracy on the telephoto side, and is therefore used in higher-end video cameras for home use and video cameras for business use. Often.

[0004] This optical image stabilizer is generally
An optical axis angle variable optical system capable of controlling the transmitted optical axis angle is provided in front of the image sensor, and shakes (changes in direction) of the video camera.
By controlling the transmitted optical axis angle of the optical axis angle variable optical system based on the angle (relative angular displacement of the photographing optical axis), the shake of the photographed image due to camera shake is suppressed. Here, the transmitted optical axis angle is an angle formed by the optical axis on the output side with respect to the optical axis on the incident side.

The above-described variable optical axis system generally has an optical element whose attitude can be controlled, and the transmitted optical axis angle can be controlled by controlling the attitude of this optical element. . Conventionally, as such an optical axis angle variable optical system, an optical axis angle variable optical system composed of an apex angle variable prism and an optical axis angle variable optical system composed of an afocal optical system are known.

[0006] As an optical axis angle variable optical system comprising a vertical angle variable prism, for example, the one described in the following document 1 is known. The variable optical axis angle optical system described in Document 1 supports a pair of glass substrates rotatably,
A variable apex angle prism is formed by sealing a liquid between the pair of glass substrates, and by changing the angle formed by the pair of glass substrates (the apex angle of the apex variable prism), the transmitted light axis angle is changed. It has become. In such a configuration, each glass substrate corresponds to an optical element, and the rotation angle of each glass substrate corresponds to a posture position of the optical element. Reference 1: JP-A-61-269572

Further, as another example of an optical axis angle variable optical system composed of an apex angle variable prism, see, for example,
The ones described in 3, 4 are known. This document 2,
The optical systems described in 3 and 4 form a vertex angle variable prism by rotatably supporting a plano-convex lens and a plano-concave lens having approximate spherical curvatures so that the spherical surfaces face each other. By changing the angle between the planes of the lenses (vertical angle of the vertical angle variable prism), the transmitted light axis angle is changed. In such a configuration,
The plano-convex lens and the plano-concave lens correspond to the optical element, and the rotation angle of each lens corresponds to the posture position of the optical element.

Document 2: JP-A-57-25803 Document 3: JP-A-06-070220 Document 4: JP-A-06-281889

As an optical axis angle variable optical system comprising an afocal optical system, for example, those described in the following documents 5 and 6 are known. The optical axis variable optical systems described in Documents 5 and 6 constitute an afocal optical system by combining one concave lens and one convex lens, and make each lens perpendicular to the optical axis and By moving them in directions perpendicular to each other, the transmitted optical axis angle is changed. In such a configuration, each lens corresponds to an optical element, and a moving position of each lens corresponds to a posture position of the optical element. Document 5: JP-A-6-118471 Document 6: JP-A-7-168235

In order to suppress the shake of a photographed image due to camera shake using the optical axis angle variable optical system as described above, in addition to the camera shake angle, the transmitted optical axis angle of the optical axis angle variable optical system is required. It is necessary to control the transmitted light axis angle of the optical axis angle variable optical system by controlling the posture position of the optical element based on both detection outputs.

Conventionally, when detecting the transmitted optical axis angle of an optical axis angle variable optical system, a driving means (for example, a motor) for an optical element is used.
By detecting the driving amount of the optical element, the transmitted light axis angle is indirectly detected.

[0012]

However, in such a configuration, if a disturbance or an unknown element exists before the driving means of the optical element, the transmitted optical axis angle of the optical system can be accurately detected. There was a problem that it disappeared. Also, at the stage of shipment from the factory, even if the transmitted optical axis angle of the optical system can be accurately detected, if the aging of the driving means of the optical element or the decrease in durability occurs, the transmission of the optical system may occur. There has been a problem that the optical axis angle cannot be accurately detected. When such a problem occurs, it becomes impossible to accurately suppress the shake of the captured image due to the shake of the video lamella. Therefore, this problem needs to be resolved immediately.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and has as its object the purpose of the present invention in the presence of a disturbance or an unknown element at the tip of a driving means for an optical element, or the aging or durability of the driving means or the like. It is an object of the present invention to provide an optical axis angle detection device, an optical axis angle variable device, and a shake correction device that can accurately detect the transmitted optical axis angle of the optical system even if a decrease or the like occurs.

[0014]

According to the present invention, the transmitted light axis angle of the optical system is detected based on the refraction angle of the light transmitted through the optical system. Specifically, the present invention provides:
A detection light irradiating means for irradiating the optical system with detection light for detecting a transmission light axis angle of the optical system, and a transmission light axis angle of the optical system based on a refraction angle of the detection light transmitted through the optical system. And an optical axis angle detecting means for detecting.

In the present invention, the optical system is irradiated with detection light for detecting the transmitted light axis angle of the optical system by the detection light irradiation means. The detection light applied to the optical system is refracted according to the transmitted light axis angle of the optical system. Then, based on the refraction angle, the optical axis angle detecting means detects the transmitted optical axis angle of the optical system.

[0016]

Embodiments of the present invention will be described below in detail with reference to the drawings.

First, a first embodiment of the present invention will be described. FIG. 1 is a diagram showing a configuration of the first exemplary embodiment of the present invention. FIG. 1 shows a typical case where the shake correction apparatus of the present invention is applied to a camera shake correction apparatus of a video camera. FIG. 1 shows the overall configuration of a video camera provided with the shake correction apparatus according to the present embodiment.

First, the overall configuration of the video camera will be described. The video camera illustrated in FIG. 1 includes a camera body 100 that captures an image of a subject and a camera shake correction device 200 that suppresses a shake of a captured image due to camera shake. The camera shake correction device 200 is configured to be detachable from the camera body 100. That is, the camera shake correction device 200 is configured as an adapter that can be used as needed. The above is the overall configuration of the video camera.

Next, the configuration of the camera body 100 will be described. A camera body 100 shown in FIG. 1 includes an imaging unit 110 that converts a subject image into an electrical imaging signal,
And a video signal processing circuit 120 that converts the imaging signal output from the output signal 0 to a video signal. The imaging unit 110 includes an imaging optical system 111 for capturing a subject image, and the imaging optical system 11.
And an image sensor 112 that converts the subject image captured by the camera 1 into an electrical image signal. Here, the imaging optical system 111 can change the focal length. In addition, the imaging element 112 is configured by, for example, a charge-coupled device.

Note that the imaging configuration of the imaging unit 110 is as follows.
It may be a single-chip imaging configuration, or a two-chip, three-chip, or four-chip type using a dichroic prism or a dichroic mirror.
A plate-type imaging configuration may be used. The above is the camera body 1
00 configuration.

Next, the configuration of the camera shake correction apparatus 200 will be described. The camera shake correction device 200 shown in FIG. 1 detects the camera shake angle of the video camera, and based on the detected output,
By controlling the transmitted light axis angle of the optical axis angle variable optical system,
The shake of the photographed image due to camera shake is suppressed. In this case, the shake angle of the video camera is, for example,
Detection is performed using two axes perpendicular to the optical axis and orthogonal to each other. As this axis, for example, an axis in the pitching P direction (tilt direction) and an axis in the yawing Y direction (pan direction) are used.

Hereinafter, the configuration of the camera shake correction apparatus 200 will be described in detail. In the following description, pitching P
The description will be made with P added to the components related to the direction, and Y added to the components related to the yawing Y direction.

A camera shake correction apparatus 200 shown in FIG. 1 calculates a shake correction mechanism 210 having a variable optical axis angle mechanism and a correction value of a rotation angle of lenses 211 (P) and 211 (Y) described later. The arithmetic unit 220 and a drive circuit 230 that drives a drive motor 218 (P) in the pitching P direction described below.
(P) and a drive motor 21 in the yawing Y direction described later.
8 (Y).
The arithmetic unit 220 is configured by, for example, a central processing unit (CPU). The function of the calculation unit 220 will be described later in detail.

The shake correcting mechanism 210 includes a plano-concave lens 211.
(P), the plano-convex lens 211 (Y), and the plano-concave lens 21
A rotating shaft 212 (P) for pivotally supporting 1 (P) in a plane perpendicular to the optical axis thereof, and a plano-convex lens 211 (Y)
And a rotation shaft 212 (Y) for pivotally supporting the lens in a plane perpendicular to the optical axis.

These constitute a variable optical axis angle mechanism. Among them, the plano-concave lens 211 (P) and the plano-convex lens 211
(Y) constitutes an optical axis angle variable optical system for changing the transmitted optical axis angle, and the rotating shafts 212 (P) and 212 (Y)
Plano-concave lens 211 (P) and plano-convex lens 211, respectively
(Y) constitutes a support mechanism. The optical system is an afocal optical system. Here, the plano-concave lens 2
11 (P) and the plano-convex lens 211 (Y) correspond to an optical element for changing a transmission optical axis angle. The configuration of the optical axis angle variable mechanism will be described later in detail.

The shake correction mechanism 210 also includes a shake detector 213 (P) for detecting the angular velocity of a hand shake in the pitching P direction of the video camera, and a shake detector 213 for detecting the angular velocity of a hand shake in the yaw Y direction. (Y). These are constituted by, for example, angular velocity sensors such as vibrating gyros.

The shake correcting mechanism 210 includes a point light source 214 for outputting detection light for detecting the transmitted light axis angle of the optical axis angle variable optical system described above, and a detection light output from the point light source 214. Into a parallel light and irradiate the variable optical axis angle optical system with a collimator lens 215 and an imaging lens 216 that converges the detection light transmitted through the variable optical axis angle optical system
And a light receiving position detector 21 that receives the detection light converged by the imaging lens 216 and detects the light receiving position.
And 7.

These constitute an optical axis angle detecting device for detecting the transmitted optical axis angle of the optical axis angle variable optical system based on the refraction angle of the detection light transmitted through the optical axis angle variable optical system.
Among them, the point light source 214 and the collimator lens 215 constitute a detection light irradiation unit that irradiates the detection light to the optical axis angle variable optical system. Further, the imaging lens 216 and the light receiving position detector 217 constitute light receiving position detecting means for receiving the detection light and detecting the light receiving position. The light receiving position detecting means detects the light receiving position of the detection light in two orthogonal axes. As the two orthogonal axes, for example, an axis in the pitching P direction and an axis in the yawing Y direction are used.

The above-described optical axis angle detecting device is provided in an area other than the maximum effective area used for photographing in the light transmitting area of the optical axis angle variable optical system. That is, the optical axis angle detection device is provided in an area other than the maximum angle of view in the light transmission area of the optical axis angle variable optical system. FIG. 2 shows an area other than the maximum angle of view. In the drawing, the hatched portions are portions other than the maximum angle of view. Note that FIG.
It is the figure which looked at (P) and 211 (P) from the front. In the present embodiment, of the parts other than the maximum angle of view, for example,
An optical axis angle detection device is provided in a portion located below the maximum angle of view.

In this optical axis angle detecting device, the optical axis (the same as the optical axes of the lenses 215 and 216) is
It is arranged so as to be parallel to the optical axes of (P) and 211 (Y).

The shake correction mechanism 210 is provided with a drive motor 218 for rotationally driving the plano-concave lens 211 (P).
(P), and a drive motor 218 (Y) that rotationally drives the plano-convex lens 211 (Y).

The above-described optical axis angle varying mechanism (lens 2)
11 (P), 211 (Y), rotating shafts 212 (P), 21
2 (Y)), the optical axis angle detection device (point light source 214, collimator lens 215, imaging lens 216, light receiving position detector 216), and drive motors 218 (P), 218 (Y) are a lens barrel. It is housed inside the housing 219. The above-described shake detectors 213 (P) and 213 (Y) are provided in the lens barrel housing 2.
It is attached to the outside of 19. The above is the configuration of the camera shake correction apparatus 200.

Next, the configuration of the optical axis angle varying mechanism will be described with reference to FIG. FIG. 3 is a perspective view showing the configuration of the optical axis angle variable mechanism. As shown in FIG.
1 (P) and the plano-convex lens 211 (Y) are configured to have substantially the same aperture and substantially the same focal length.
Further, the two lenses 211 (P) and 211 (Y) are arranged to face each other with a small space therebetween via the virtual plane A1. Thereby, both lenses 211 (P) and 211 (Y)
Constitute an afocal optical system as a whole.

In this case, both lenses 211 (P), 211
(Y), as shown in FIG. 1, are arranged to face each other such that the planes face each other. Also, both lenses 211
(P) and 211 (Y) are arranged such that the coaxial optical axis B (see FIG. 3) coincides with the optical axis of the imaging optical system 111. Thereby, both lenses 211 (P) and 211 (Y)
Are arranged such that the coaxial optical axis B coincides with the center of the image area of the image sensor 112. Here, the coaxial optical axis B refers to an optical axis when the optical axes of both lenses 211 (P) and 211 (Y) are made to coincide.

The plano-concave lens 211 (P) is rotated by a pivot shaft 212 (P) via a bearing 1a (P) provided on the outer edge thereof.
It is rotatably supported on the shaft. This rotating shaft 212 (P)
Is disposed parallel to the optical axis of the plano-concave lens 211 (P). Thus, the plano-concave lens 211 (P) is pivotally supported so as to be rotatable in a plane perpendicular to the optical axis.

The plano-convex lens 211 (Y) is rotated by a pivot shaft 212 (Y) via a bearing 1a (Y) provided on the outer edge thereof.
It is rotatably supported on the shaft. This rotating shaft 212 (Y)
Is disposed parallel to the optical axis of the plano-convex lens 211 (P). Thus, the plano-convex lens 211 (P) is pivotally supported so as to be rotatable in a plane perpendicular to the optical axis.

In this case, the rotating shafts 212 (P), 212
(Y) is positioned such that a plane A2 including the rotation axis 212 (P) and the coaxial optical axis B and a plane A3 including the rotation axis 212 (Y) and the coaxial optical axis B are substantially orthogonal to each other. ing. Thereby, the lenses 211 (P) and 211 (Y) are rotated in directions substantially orthogonal to each other.

Further, the rotating shaft 212 (P) has a coaxial optical axis B
Are positioned on a horizontal line (a straight line in the yawing Y direction) C (Y) that passes through. Thereby, the plano-concave lens 211
(P) is rotated along the pitching P direction.
Similarly, the rotation shaft 212 (Y) is positioned on a vertical line (a straight line in the pitching P direction) C (P) passing through the coaxial optical axis B. Thereby, the plano-concave lens 211 (Y) is rotated along the yawing Y direction. The above is the configuration of the optical axis angle variable mechanism.

The pivot 2 of the plano-concave lens 211 (P)
The drive motor 218 (P) described above is directly connected to 12 (P) from the side opposite to the virtual plane A1 side. Similarly,
The above-described drive motor 218 (Y) is directly connected to the rotation shaft 212 (Y) of the plano-convex lens 211 (Y) from the side opposite to the virtual plane A1 side.

Next, the function of the arithmetic unit 220 will be described. The calculation unit 220 includes a shake detector 213 (P), 2
13 (Y) based on the detection output.
The target values of the rotation angles of (P) and 211 (Y) are determined, and the current values of the rotation angles of the lenses 211 (P) and 211 (Y) are determined based on the detection output of the light receiving position detector 217. And lenses 211 (P) and 211 for suppressing image blur due to camera shake by calculating the difference between the two.
It has a function of obtaining a correction value of the rotation angle of (Y).

The lenses 211 (P) and 211 (Y)
Corresponds to the transmitted optical axis angle of the optical axis angle variable optical system. Therefore, obtaining the target value, the current value, and the correction value of the rotation angle of the lenses 211 (P) and 211 (Y) is based on the target value, the current value, and the correction of the transmitted optical axis angle of the optical axis angle variable optical system, respectively. Corresponds to finding a value.

The calculating section 220 is provided for the one lens 21.
The displacement of the lens 211 (P) or 211 (Y) from the optical axis angle variable direction caused by the rotation of 1 (P) or 211 (Y) (hereinafter referred to as "orthogonal error").
And a function for calculating a correction value of the rotation angle of the other lens 211 (Y) or 211 (P) necessary to cancel the orthogonal direction error. Here, the optical axis angle variable direction refers to a direction in which the transmitted optical axis angle is changed. This optical axis angle variable direction is the pitching P direction in the case of the plano-concave lens 211 (P), and is the yawing Y direction in the case of the plano-convex lens 211 (Y). The above is the function of the arithmetic unit 220.

The operation of the above configuration will be described. First, the imaging operation of the video camera will be described.

In FIG. 1, a subject image is represented by a lens 211.
(P) and 211 (Y) are connected to the image sensor 112 via the image pickup optical system 111. The subject image formed on the image sensor 112 is converted into an electrical image signal by the image sensor 112. The image signal is converted into a video signal by the video signal processing circuit 120. This video signal is recorded on a magnetic tape by a recording / reproducing unit (not shown), for example. The above is the imaging operation of the video camera.

Next, the overall operation of the camera shake correction apparatus 200 will be described.

When no camera shake occurs, the lens 21
1 (P) and 211 (Y) are positioned such that the optical axis coincides with the center of the image area. In this state,
When a camera shake occurs, the angular velocity of the camera shake in the pitching P direction is detected by the shake detector 211 (P), and the angular velocity in the yawing Y direction is detected by the shake detector 215 (Y). As a result, the angular velocity of the shake in all directions of the video camera is detected as orthogonal biaxial components. This detection output is supplied to the calculation unit 220.

In parallel with this, the lenses 211 (P), 2
The current value of the rotation angle of 11 (Y) (corresponding to the transmitted light axis angle) is determined by the optical axis angle detection device (point light source 214, collimator lens 21).
5, detected by the imaging lens 216 and the light receiving position detector 217). This detection is performed based on the refraction angle of the detection light transmitted through the optical axis angle variable optical system (the lenses 211 (P) and 211 (Y)). This detection output is supplied to the calculation unit 220.

The calculation unit 220 includes a shake detector 215
Based on the detection outputs of (P) and 215 (Y) and the detection output of the optical axis angle detection device, lenses 211 (P) and 211 (P)
A difference value between the target value and the current value of the rotation angle of (Y) is obtained. This difference value is calculated by using the lenses 211 (P) and 211 (Y).
The drive circuit 230 (P), 2
30 (Y). Thereby, the lens 211
(P), 211 (Y) drive motor 218 (P), 21
8 (Y) is driven. As a result, the lens 211
The rotation angles of (P) and 211 (Y) are set to target values. Thereby, the shake of the captured image due to the camera shake is suppressed.

Thereafter, the arithmetic section 220 detects an error in the orthogonal direction of one of the lenses 211 (P) or 211 (Y) based on the detection output of the optical axis angle detecting device. Then, a correction value of the rotation angle of the other lens 211 (Y) or 211 (P) necessary to cancel the orthogonal direction error is calculated. This correction value is calculated based on the value of the other lens 211.
(Y) or 211 (P) drive circuit 230 (Y),
230 (Y). As a result, the drive motor 218 for the other lens 211 (Y) or 211 (P)
(P) and 218 (Y) are driven. As a result, the other lens 211 (Y) or 211 (P) is rotated in a direction to cancel the orthogonal error of the one lens 211 (P), 211 (Y). Thereby, one lens 2
The shake of the captured image due to the orthogonal error of 11 (P) and 211 (Y) is suppressed. The above is the overall operation of the camera shake correction device.

Next, an optical axis angle variable mechanism (lens 211)
(P), 211 (Y), rotating shafts 212 (P), 212
The optical axis angle changing operation of (Y)) will be described.

FIGS. 4 to 6 show the lenses 211 (P) and 2 (P).
It is a figure showing rotation of 11 (Y). 4 to 6
Is a front view of the lenses 211 (P) and 211 (Y) as viewed from the front of a video camera, for example. Here, FIG.
Shows the rotation of the plano-concave lens 211 (P), FIG. 5 shows the rotation of the plano-convex lens 211 (Y), and FIG.
11 shows a state where the rotations of 11 (P) and 211 (Y) are overlapped.

As shown in FIG. 4, the plano-concave lens 211
(P) is a positive side (for example, upper side in the figure) or a negative side (for example, lower side in the figure) about the horizontal line C (Y).
Is rotated. The figure shows a state in which the plano-concave lens 211 (P) is rotated by an angle θ to the positive side or the negative side about the horizontal line C (Y). T (P) represents the movement locus of the optical axis center D (P) of the plano-concave lens 211 (P) at this time.

As shown, the movement locus D (P) of the optical axis center D (P) of the plano-concave lens 211 (P) is represented by a vertical line C
It is like drawing an arc tangent to (P). As a result, the transmitted optical axis angle is displaced in a direction different from the pitching P direction (optical axis angle variable direction) by the rotation of the plano-concave lens 211 (P).

However, the camera shake angle of the video camera in the pitching P direction is usually about ± 0.3 degrees. Therefore, the rotation angle θ of the plano-concave lens 221 (P) required to correct the camera shake becomes small.
Thereby, the optical axis center D of the plano-concave lens 221 (P) is obtained.
The movement trajectory T (P) of (P) can be regarded as substantially along the pitching P direction. As a result, the displacement of the transmitted optical axis angle due to the rotation of the plano-concave lens 221 (P) can be regarded as substantially along the pitching P direction.

Further, as shown in FIG.
1 (Y) is a positive side (for example, the right side in the figure) or a negative side (for example, the left side in the figure) around the vertical line C (P).
Is rotated. The figure shows a state in which the plano-convex lens 211 (Y) is rotated by an angle θ to the positive side or the negative side about the vertical line C (P). T (Y) indicates the movement locus of the optical axis center D (Y) of the plano-convex lens 211 (Y) at this time.

As shown in the figure, the movement trajectory T (Y) of the optical axis center D (Y) of the plano-convex lens 211 (Y) is
By the rotation of 11 (P), an arc that touches the horizontal line C (P) is drawn. Thereby, the transmitted light axis angle is displaced in a direction different from the yawing Y direction (optical axis angle variable direction).

However, the camera shake angle in the yawing Y direction of the video camera is usually about ± 0.3 degrees. Therefore, the rotation angle の of the plano-convex lens 221 (Y) required to correct the camera shake can be small.
Thereby, the optical axis center D of the plano-convex lens 221 (P) is obtained.
The movement trajectory T (P) of (P) is substantially along the yawing Y direction. As a result, the plano-concave lens 221 (P)
The displacement of the transmitted light axis angle due to the rotation of the axis also substantially follows the yawing Y direction.

The center D of the transmitted light axis is, as shown in FIG.
The displacement vector of the optical axis center D (P) of the plano-concave lens 211 (P) in the optical axis angle variable direction and the displacement vector of the optical axis center D (Y) of the plano-convex lens 211 (Y) in the optical axis angle variable direction are calculated as follows. Are obtained by synthesizing Thus, the transmitted light axis angle is displaced in all directions defined by two orthogonal axes, similarly to the case of the apex angle variable prism capable of displacing the transmitted light axis angle two-dimensionally.

FIG. 7 is a diagram showing an example of a state in which the transmitted light axis angle is displaced to the positive side in the pitching P direction. Now, it is assumed that the lenses 211 (P) and 211 (Y) are located at positions where the optical axes coincide. In this state, the plano-concave lens 211
When a light beam such as subject light parallel to the optical axis enters (P), the focal point F of the plano-concave lens 211 (P)
A virtual image is formed. Thereby, this plano-concave lens 21
From 1 (P), divergent light is emitted using the focal point F as an imaginary light source. This divergent light is incident on the plano-convex lens 211 (Y). The focal length of this plano-convex lens 211 (Y) is
It is the same as the focal length of the plano-concave lens 211 (P). As a result, parallel light is emitted from the plano-convex lens 211 (Y) using the imaginary light source as the light source of the focal point F.

In this state, as shown in FIG. 7, when the plano-concave lens 211 (P) is displaced by the distance y to the negative side in the pitching P direction, the transmitted optical axis angle is displaced by α to the positive side in the pitching P direction. Can be Thereby, the plano-convex lens 211
From (Y), as shown in FIG. 7, parallel light displaced by an angle α from the optical axis of the incident light is emitted. In this case, the angle α is represented by the following equation (1), where f is the focal length of the lenses 211 (P) and 211 (Y). α = tan ^-1 (y / f) (1)

Although a detailed description is omitted, when the plano-concave lens 211 (P) is displaced to the positive side in the pitching P direction, the transmitted optical axis angle is displaced to the negative side in the pitching P direction. When the plano-convex lens 211 (Y) is displaced to the positive side or the negative side in the yawing Y direction, the transmitted optical axis angle is displaced to the negative side or the positive side in the yawing Y direction.

As described above, the lenses 211 (P) and 211 (P)
By rotating (Y), the transmitted light axis angle can be displaced in all directions defined by two orthogonal axes. Thereby, the shake of the captured image due to the hand shake can be suppressed. The above is the optical axis variable operation of the optical axis variable mechanism.

Next, the problem of the optical axis angle varying mechanism and its solution will be described. As described above, in order to suppress the shake of the captured image due to the camera shake, the lens 211 is used.
When (P) and 211 (Y) are rotated in the optical axis angle variable direction, the circular motion causes the lenses 211 (P) and 211 (Y) to rotate.
The optical axis centers D (P) and D (Y) of (Y) are shifted in a direction orthogonal to the optical axis angle variable direction. When this orthogonal direction error occurs, there arises a problem that the captured image also shakes in a direction orthogonal to the direction of the shake caused by the camera shake.

To cope with this problem, in the present embodiment, one of the lenses 211 (P) or 211 (Y) is used.
By rotating the other lens 211 (Y) or 211 (P) based on the rotation angle of, the orthogonality error is canceled. Thereby, it is possible to suppress the shake of the captured image due to the orthogonal walking error.

Hereinafter, this will be described in detail with reference to FIGS. FIG. 8 shows a plano-concave lens 211 (P).
Is rotated by θ to the positive side in the pitching P direction. In this case, the optical axis center D of the plano-concave lens 211 (P)
As shown in FIG. 9, (P) moves to the positive side in the pitching P direction (optical axis angle variable direction) by y and also moves to the negative side in the yawing Y direction (direction orthogonal to the optical axis angle variable direction). Move by Δx.

In this case, y and Δx are the values of the plano-concave lens 211.
Assuming that the radius of (P) is r, the following equations (2) and
It is represented by (3). y = r · sin θ (2) Δx = y · tan θ = r · sin θ · tan θ (3) Here, Δx corresponds to an error in the orthogonal direction. Due to the occurrence of the orthogonal direction error Δx, the captured image swings to the positive side in the yawing Y direction.

In order to deal with this problem, in the present embodiment, as shown in FIG. 10, the optical axis center D (Y) of the plano-convex lens 211 (Y) is turned by an angle に toward the negative side in the yawing Y direction. By moving, the orthogonal direction error Δx is canceled. In this case, the angle ψ is expressed by the following equation (5) from the following equation (4). sinψ = x / r = sin θ · tan θ (4) ψ = sin ⁻¹ (sin θ · tan θ) (5)

By rotating the plano-convex lens 211 (Y) to the negative side in the yawing Y direction by an angle ψ, the plano-convex lens 211 (Y) is shifted to the negative side in the yawing Y direction by Δ.
Not only can it be moved by x, but also by Δy on the negative side in the pitching P direction. As a result, the captured image swings to the positive side in the pitching P direction.

However, this orthogonal direction error Δy is extremely small. For example, the orthogonal direction error Δx is about one hundredth of the movement amount y, and the orthogonal direction error Δy is about one hundredth thereof. Therefore, the shake of the photographed image due to the orthogonal direction error Δy has almost no visual problem. Therefore, in the present embodiment, the cancellation of the orthogonal direction error Δy is not performed.

Although the detailed description is omitted, the above-mentioned problem is caused by the fact that the plano-concave lens 211 (P) is pitched P
Not only does it rotate to the positive side of the direction, but also to the negative side. In this case, the plano-convex lens 211
(Y) may be turned to the positive side in the yawing Y direction.
Such a problem also occurs when the plano-convex lens 211 (Y) is rotated to the positive side or the negative side in the yawing Y direction. In this case, the plano-concave lens 211 (P) may be turned to the negative side or the positive side in the pitching P direction.

FIG. 11 shows the displacement y and the orthogonal direction of the optical axis center D (P) of the plano-concave lens 211 (P) when the plano-concave lens 211 (P) is rotated by θ to the positive side in the pitching P direction. The error Δx and the plano-convex lens 21 when the plano-convex lens 211 (Y) is rotated by 回 動 to the positive side in the yawing Y direction
FIG. 3 is a diagram showing a displacement amount x and an orthogonal direction error Δy of an optical axis center D (Y) of 1 (Y).

In this case, in order to cancel the error Δx in the orthogonal direction of the optical axis center D (P) of the plano-concave lens 211 (P),
Place the plano-convex lens 211 (Y) on the negative side in the yawing Y direction by Δ
It only needs to be turned by ψ. Also, the plano-convex lens 211
To cancel the error Δy in the orthogonal direction of the optical axis center D (Y) of (Y), the plano-concave lens 211 (P) may be rotated by Δθ to the negative side in the yawing Y direction. The above is the problem of the optical axis angle variable mechanism and its solution.

Next, the operation of detecting the optical axis angle of the optical axis angle detecting device (point light source 214, collimator lens 215, imaging lens 216, light receiving position detector 217) will be described with reference to FIG.

The detection light output from the point light source 214 is converted into parallel light by the collimator lens 215, and then is changed into an optical axis angle variable optical system (lenses 211 (P) and 211 (Y)).
Is irradiated. The detection light applied to the optical axis angle optical system is converged by the imaging lens 216 after passing through the optical axis angle optical system. This converged light is received by the light receiving position detector 217.
And the light receiving position is detected. This detection output is supplied to the calculation unit 220.

Here, the detection light applied to the optical axis angle variable optical system is refracted according to the rotation angles of the lenses 211 (P) and 211 (Y). The principle of this refraction is the same as the above-described principle of refraction of the transmission optical axis. The angle of refraction is
It is the same as the transmitted light axis angle. Therefore, by detecting the light receiving position of the detection light, the lenses 211 (P) and 211 (P) are detected.
The rotation angle of (Y) is detected.

Next, referring to FIG.
The operation of 0 will be described in detail. Note that FIG.
20 is a flowchart showing a process 20. The drive control system of the camera shake correction apparatus 200 (the arithmetic unit 220, the drive circuit 230
(P), 230 (Y), drive mode 213 (P), 213
(A part consisting of (Y)) is a main switch (not shown)
Is activated by the input of, and is set to the end state by disconnection. The process in FIG. 12 is started when a power switch (not shown) of the camera shake correction device 200 is turned on, and ends when the power switch is turned off.

In this process, first, the shake detector 2
A process for taking in the detection outputs 15 (P) and 215 (Y) is executed (step S101). Thus, the data indicating the angular velocity ω (P) of the camera shake in the pitching P direction of the video camera and the angular velocity ω of the camera shake in the yawing Y direction
The data indicating (Y) is fetched.

When the taking process is completed, an integrating process is performed in which the taken angular velocities ω (P) and ω (Y) are added to the cumulative addition values of the angular velocities ω (P) and ω (Y) up to the previous time, respectively. (Step S101). As a result, the swing angle W (P) of the video camera in the current pitching P direction is obtained.
And yaw Y-direction deflection angle W (Y)
Is obtained.

When the integration process is completed, a process for taking in the detection output of the light receiving position detector 217 is executed (step S103). Accordingly, the data indicating the coordinate value yn of the light receiving position of the detection light in the pitching P direction and the yawing Y
And data indicating the coordinate value xn of the direction. The coordinates xn, yn on the lenses 211 (P), 211 (Y) correspond to the coordinates x, y of the optical axis center D of the transmission optical axis shown in FIG.

When this capture processing is completed, the shake of the photographed image due to camera shake is suppressed based on the shake angles W (P), W (Y) of the video camera and the coordinate values yn, xn of the light receiving position of the detection light. Lenses 211 (P), 211
A correction value of the rotation angle of (Y) is obtained, and the driving circuit 230
(P), the process of supplying the signal to 230 (Y) is executed (step S104).

The correction values of the rotation angles of the lenses 211 (P) and 211 (Y) are obtained by obtaining the target value and the current value of the rotation angles of the lenses 211 (P) and 211 (Y). It is obtained by obtaining a difference value. In this case, lens 2
The target values of the rotation angles of 11 (P) and 211 (Y) are obtained based on the shake angles W (P) and W (Y) of the video camera, respectively. Also, lenses 211 (P), 211
The current value of the rotation angle of (Y) is obtained based on the coordinate values yn and xn of the light receiving position of the detection light.

If the above-described processing for obtaining the correction value is the first processing after the power switch of the camera shake correction apparatus 200 is turned on, the lenses 211 (P) and 211 (Y)
Is zero. This is because when the power switch is turned on, the lenses 211 (P) and 211 (Y) are arranged at the center. Therefore, the correction value in this case corresponds to the rotation angles θ and ψ shown in FIG.

The obtained correction value is supplied to the driving circuit 230
(P), 230 (Y). Thus, the lenses 211 (P) and 211 (Y) are rotated by this correction value. As a result, the lenses 211 (P), 211
The rotation angle of (Y) is set to the target value. This allows
Shake of the captured image due to camera shake is suppressed.

When the correction value calculation output processing is completed, the processing for taking in the detection output of the light receiving position detector 217 is executed again (step S105). As a result, the data indicating the coordinate value yn in the pitching P direction and the data indicating the coordinate value xn in the yawing Y direction of the light receiving position of the detection light after performing the camera shake correction are fetched.

When the taking process is completed, one of the lenses 211 based on the taken coordinate values yn and xn.
The other lenses 211 (Y), 211 for canceling the orthogonal errors Δxn, Δyn of (P), 211 (Y).
The process of obtaining the correction values Δθ, Δψ of the rotation angle of (P) and supplying the correction values to the drive circuits 230 (Y), 230 (P) is executed (step S106). In this process, the lenses 211 (P) and 211 (P) are set based on the acquired coordinate values yn and xn.
The orthogonal direction errors Δxn and Δyn of (Y) are obtained, and the lens 211 corresponding to the orthogonal direction errors Δxn and Δyn
(Y) and 211 (P) are obtained by determining the rotation angle.

The obtained correction values Δθ and Δψ are used as the driving circuits 230 for the other lenses 211 (Y) and 211 (P).
(Y) and 230 (P). As a result, the other lenses 211 (Y) and 211 (P) apply this correction value Δ
Rotated by θ, Δψ. As a result, the orthogonal errors Δxn, Δx of one of the lenses 211 (P), 211 (Y) are obtained.
yn is canceled. Thereby, one of the lenses 211
(P), the shake of the captured image due to the orthogonal errors Δxn, Δyn of 211 (Y) is suppressed.

When the correction value calculation output process is completed, a process for determining whether or not the power switch of the camera shake correction device 200 has been turned off is executed (step S107). If the power switch is not turned off, step S101
And the above-described processing is executed again. Hereinafter, similarly, the above-described processing is repeated until the power switch is turned off. When the power switch is turned off in this state,
The processing of the arithmetic unit 220 ends. The above is the calculation unit 22
0 operation.

According to the present embodiment described in detail above, the lens 211 based on the refraction angle of the detection light transmitted through the optical axis angle variable optical system (lenses 211 (P) and 211 (Y)).
(P), Rotation angle of 211 (Y) (corresponding to transmitted light axis angle)
Is detected, the rotation angle can be directly detected. Thereby, the lens 211
(P), 211 (Y) drive motor 218 (P), 21
8 (Y), even if there is a disturbance, an unknown element, or the like, or if the drive motors 218 (P), 218 (Y), etc. change over time or decrease in durability, etc. ), 2
The rotation angle of 11 (Y) can be accurately detected.

Further, according to the present embodiment, by detecting the light receiving position of the detection light, the lenses 211 (P),
Since the rotation angle of 11 (Y) is detected, the rotation angle can be detected with a simple configuration.

Further, according to the present embodiment, the optical axis angle detecting device (point light source 214, collimator lens 215, imaging lens 216, light receiving position detector 217) is connected to the lens 211.
(P) and 211 (Y) are provided outside the maximum angle of view, so that detection light for detecting the rotation angles of the lenses 211 (P) and 211 (Y) is provided in the image area of the image sensor 112. It can be prevented from entering as much as possible.

In the above description, when the shake of the video camera is detected, the angular velocities ω (P), ω
The case where (Y) is detected has been described. However, in the present embodiment, an angular acceleration, an acceleration, or the like of camera shake may be detected.

In the above description, the lens 211
When controlling the rotation angles of (P) and 211 (Y), a difference value between the target value and the current value of the rotation angle of the lenses 211 (P) and 211 (Y) is obtained, and the lens 211 is adjusted by the difference value.
The case where (P) and 211 (Y) are rotated has been described. However, in the present embodiment, for example, the lens 211
The rotation angles of (P) and 211 (Y) are sequentially detected, and the lens 211 is adjusted so that the rotation angle matches the target value.
The rotation angles of (P) and 211 (Y) may be controlled.

Next, a second embodiment of the present invention will be described in detail. FIG. 13 is a side view showing the configuration of the present embodiment. In FIG. 13, the same parts as those in FIG. 5 are denoted by the same reference numerals, and detailed description will be omitted.

FIG. 13 differs from FIG. 5 in that a point light source 214 and a collimator lens 215 of an optical axis angle detecting device are arranged on the exit side of an optical axis angle variable optical system, and an image forming lens 216 is provided.
And the light receiving position detector 217 is disposed on the incident side of the optical axis angle variable optical system.

According to such a configuration, the lens 211
Detection light for detecting the rotation angles of (P) and 211 (Y) is output to the side opposite to the image sensor 112. This makes it possible to reduce the amount of detection light input to the image area of the image sensor 112 compared to the above embodiment.

Next, a third embodiment of the present invention will be described in detail. FIG. 14 is a side view showing the configuration of the present embodiment. In FIG. 14, the same parts as those in FIG.
The same reference numerals are given and the detailed description is omitted.

FIG. 14 differs from FIG. 13 in that the optical axis of the optical axis angle detector (the optical axes of the lenses 215 and 216) is inclined with respect to the optical axes of the lenses 211 (P) and 211 (Y). It was made. In this case, the direction of the inclination is set so that the optical axis of the optical axis angle detection device gradually separates from the optical axes of the lenses 211 (P) and 211 (Y) toward the traveling direction of the detection light. I have.

According to such a configuration, the detection light output from the point light source 214 is transmitted to the lenses 211 (P) and 211 (P).
It travels in a direction away from the optical axis of (Y). This allows
Even when the detection light is refracted toward the optical axis of the lenses (P) and 211 (Y), it is possible to prevent the detection light from entering the photographing light as much as possible.

Further, according to such a configuration, the detection light reflected by the plano-convex lens 211 (Y) travels toward the inner wall side of the lens barrel housing 2129, so that the reflected light becomes stray light and becomes shooting light. It can be prevented from entering as much as possible.

In the above description, this embodiment is described as follows.
As in the second embodiment, the point light source 214 and the collimator lens 215 are arranged on the emission side of the optical axis angle variable optical system, and the imaging lens 216 and the light receiving position detector 217 are arranged on the incidence side. The case where the present invention is applied to such a configuration as described above has been described. However, in this embodiment, as in the first embodiment, the point light source 214 and the collimator lens 215 are disposed on the incident side of the optical axis angle variable optical system, and the imaging lens 216 and the light receiving position detection are performed. Alternatively, the present invention may be applied to a configuration in which the container 217 is disposed on the emission side.

Although the three embodiments of the present invention have been described in detail, the present invention is not limited to the above embodiments.

For example, in the above embodiment, the present invention
The case where the present invention is applied to a camera shake correction apparatus using an afocal optical system of a type in which a lens is rotationally driven as an optical axis angle variable optical system has been described. However, the present invention can also be applied to a camera shake correction apparatus using an afocal optical system that linearly drives a lens, such as the optical systems described in the above-mentioned documents 5 and 6.

In the above embodiment, the case where the present invention is applied to a camera shake correction apparatus using an afocal optical system as the optical axis angle variable optical system has been described. However, the present invention can also be applied to a camera shake correction device using a variable angle prism. In short, the present invention has an optical element capable of controlling the posture position, and has a variable optical axis angle optical system capable of controlling the transmitted optical axis angle by controlling the posture position of the optical element. The present invention can be applied to general devices.

In the above embodiment, the case where the entire camera shake correction device 200 is configured as an adapter has been described. However, in the present invention, a part thereof may be configured as an adapter. For example, the arithmetic unit 220 and the driving circuits 230 (Y) and 230 (P)
00, and only the shake correction mechanism 210 may be configured as an adapter.

In the above embodiment, the case where the camera shake correction device 200 is configured as an adapter has been described. However, in the present invention, this may be built in the video camera.

Further, in the above embodiment, the case where the present invention is applied to a camera shake correction device of a video camera has been described. However, the present invention can also be applied to a camera shake correction device of an imaging system other than a video camera.
For example, the present invention can be applied to a camera shake correction device of an electronic still camera.

In the above embodiment, the case where the present invention is applied to a camera shake correction device has been described. However, the present invention can also be applied to a shake correction device that suppresses shake of a captured image due to shake other than camera shake. For example, the present invention can also be applied to a shake correction device of an imaging system that is fixedly used on a tripod, such as a movie camera. This is because even in such an imaging system, a shake of a captured image may occur due to externally applied vibration.

Further, the present invention can be applied to a shake correction device of an optical system other than the imaging system for photographing an image. For example, the present invention can be applied to a shake correction device of an optical system such as a projector that projects an image. In addition, the present invention can be applied to a shake correction device of an optical system that simply forms an image, such as a telescope.

In the above description, a case has been described in which the present invention is applied to a shake correction device that controls the transmitted light axis angle in order to suppress shake. However, the present invention can also be applied to an apparatus that positively changes the transmitted optical axis angle regardless of the suppression of the shake.

In addition, it goes without saying that the present invention can be variously modified and implemented without departing from the scope of the invention.

[0111]

As described above in detail, according to the optical axis angle detecting device according to the first aspect, the optical axis angle varying device according to the second aspect, and the shake correcting device according to the third and fourth aspects, the optical system can be configured as follows. Since the transmitted light axis angle of the optical system is detected based on the refraction angle of the transmitted light, the transmitted light axis angle can be directly detected. This allows the transmitted optical axis angle of the optical system to be accurately determined even if there is a disturbance or an unknown element ahead of the driving means of the optical element, or if the driving means or the like changes over time or decreases in durability. Can be detected.

According to the shake correcting apparatus of the fifth aspect, the transmitted light axis angle of the optical system is detected by detecting the light receiving position of the light transmitted through the optical system. The transmitted light axis angle can be detected with a simple configuration.

According to the image stabilizing apparatus of the sixth aspect, the optical axis angle detecting device is provided outside the effective area used for photographing in the light transmitting area of the optical system. Detection light for detecting the optical axis angle can be prevented from entering the image area of the image sensor as much as possible.

Further, according to the shake correcting apparatus of the present invention, since the detection light is outputted from the emission side of the optical system, the detection light can be outputted in a direction opposite to the image pickup device. Thereby, it is possible to prevent the detection light from entering the image area of the image sensor as much as possible.

According to the shake correcting apparatus of the eighth aspect, the optical axis angle detecting device is disposed such that its optical axis is away from the optical axis of the optical element in the traveling direction of the detection light. The detection light can be prevented from entering the original light of the optical system as much as possible.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a first exemplary embodiment of the present invention.

FIG. 2 is a diagram for explaining an arrangement position of an optical axis angle detection device according to the first embodiment.

FIG. 3 is a perspective view illustrating a configuration of an optical axis angle varying mechanism according to the first embodiment.

FIG. 4 is a diagram illustrating rotation of the plano-concave lens according to the first embodiment.

FIG. 5 is a diagram illustrating rotation of the plano-convex lens according to the first embodiment.

FIG. 6 is a diagram illustrating a state in which the plano-concave lens and the plano-convex lens according to the first embodiment are rotated one upon another.

FIG. 7 is a diagram for explaining the operation of the optical axis angle varying mechanism according to the first embodiment.

FIG. 8 is a diagram for explaining the operation of the optical axis angle varying mechanism according to the first embodiment.

FIG. 9 is a diagram for explaining the operation of the optical axis angle variable mechanism according to the first embodiment.

FIG. 10 is a diagram for explaining an operation of the optical axis angle varying mechanism according to the first embodiment.

FIG. 11 is a diagram for explaining the operation of the optical axis angle varying mechanism according to the first embodiment.

FIG. 12 is a flowchart for explaining the operation of the calculation unit according to the first embodiment.

FIG. 13 is a diagram showing a configuration of a second exemplary embodiment of the present invention.

FIG. 14 is a diagram showing a configuration of a third exemplary embodiment of the present invention.

[Explanation of symbols]

100: camera body, 110: imaging units 110, 111 ...
Image pickup optical system, 112: Image sensor, 120: Video signal processing circuit, 200: Camera shake correction device, 210: Camera shake correction mechanism, 220: Calculation unit, 230 (P), 230 (Y): Drive circuit, 211 (P) ... plano-concave lens, 211 (Y) ... plano-convex lens, 212 (P), 212 (Y), rotating shaft, 21
3 (P), 213 (Y): shake detector, 214: point light source, 215: collimator lens, 216: imaging lens,
217: light receiving position detector, 218 (P), 218 (Y)
... drive motor, 219 ... lens barrel housing.

Claims (8)

[Claims] An optical element capable of controlling a posture position,
By controlling the attitude position of the optical element, an optical axis angle detecting device for detecting the transmitted optical axis angle of the optical system capable of controlling the transmitted optical axis angle, comprising: A detection light irradiation unit that irradiates detection light for detection; and an optical axis angle detection unit that detects a transmitted light axis angle of the optical system based on a refraction angle of the detection light transmitted through the optical system. An optical axis angle detecting device, characterized in that: 2. An optical element having a controllable attitude and position.
An optical system capable of controlling a transmitted optical axis angle by controlling a posture position of the optical element; and an optical axis detecting a transmitted optical axis angle of the optical system based on a refraction angle of light transmitted through the optical system. Angle detection means, and an optical axis angle control means for controlling a transmission optical axis angle of the optical system by controlling a posture position of the optical element based on a detection output of the optical axis angle detection means. An optical axis angle varying device, characterized in that: 3. An image stabilizing apparatus for suppressing image shake caused by shake of an optical system for forming an image, comprising an optical element capable of controlling a posture position, and controlling the posture position of the optical element. An optical system capable of controlling a transmitted light axis angle, an optical axis angle detecting means for detecting a transmitted light axis angle of the optical system based on a refraction angle of light transmitted through the optical system, and a shake of the optical system. A shake detection means for detecting, and a position of the optical element being controlled based on a detection output of the shake detection means and a detection output of the optical axis angle detection means, thereby obtaining an image of the image due to the shake of the optical system. A shake correction device comprising: a shake suppression unit that suppresses shake. 4. The optical axis angle detecting means, wherein the optical system is radiated with detection light for detecting a transmitted light axis angle of the optical system, and the optical system transmits the optical system. 4. The apparatus according to claim 3, further comprising a detecting unit configured to detect a transmitted light axis angle of the optical system based on a refraction angle of the detection light. 5. The apparatus according to claim 1, wherein the detecting unit receives the detection light transmitted through the optical system, and detects a transmitted light axis angle of the optical system based on a light receiving position. The shake correction apparatus according to claim 4, wherein 6. The shake correction apparatus according to claim 4, wherein the detection light irradiation unit and the detection unit are provided outside an effective area of the optical system. 7. The image stabilizing apparatus according to claim 4, wherein said detecting light irradiating means is provided on an emission side of said optical system, and said detecting means is provided on an incident side of said optical system. apparatus. 8. The detecting light irradiation means and the detecting means,
The shake correction apparatus according to claim 4, wherein the optical axis is disposed so as to be separated from the optical axis of the optical element in a traveling direction of the detection light.