JPH10186432A - Apex angle variable prism device, and camera shake correcting device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To electrically correct the deviation of a lens when another lens is rotated. SOLUTION: The apex angle variable prism 2 in which spherical lenses 3 and 4 are arranged having their spherical swifaced opposed to each other, is provided in the front of an optical system. Shake in two axial directions orthogonal to the optical axis of an image pickup device is detected by sensors 203 and 204 and the rotational angles of the lenses 3 and 4 are adjusted according to outputs from the sensors. At such a time, the rotational angles of the lenses 4 and 3 are corrected by utilizing the outputs from the sensors. For example, when the lens 3 is rotated and inclined an error component ϕxy due to the rotation is generated. In order to cancel the signal ϕxy, Sy=ϕxy is added to the other lens 4. At the time when the lens 4 is in an already inclined state (ϕyy≠0), the lens 4 is corrected by adding the difference, Sy=ϕxy-ϕyy. When the camera shake occurs in y-axis direction, an integration signal ϕLy related to the sensor 204 is obtained, and then the optical axis correcting signal Sy to be added to the lens 4 finally becomes Sy=ϕLy+ϕxy-ϕyy.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a doublet-type variable apex angle prism device having two spherical lenses arranged so that their spherical surfaces face each other, and a shake correction device using the same. More specifically, the optical axis of the prism can be varied by slightly rotating the center of each spherical surface of the plano-concave and plano-convex lenses around the center of the spherical surface, and the optical axis can be varied. This is to correct the deviation of the rotation angle between the two lenses, which occurs when the rotation axis of the lens is selected on a straight line passing through the center of the lens spherical surface.

[0002]

2. Description of the Related Art In recent years, a camera shake correction device has been provided to suppress a shake of a shot image due to vibration (camera shake) transmitted to a camera at the time of shooting with a television camera. This is achieved by mounting a detection sensor (angular velocity detection sensor, acceleration detection sensor, etc.) for detecting the angle and posture of the camera body in the TV camera, and according to the output, a variable prism (camera shake correction device) By changing the apex angle of (1) and tilting the optical axis, the shaking of the image due to the shaking of the camera body is canceled.

As such a camera shake correction apparatus, for example, Japanese Patent Laid-Open No. 61-269572 is known. The vertical angle variable prism used as this camera shake correction device encloses a special liquid in the lens optical axis by sandwiching it with a plate glass, and changes the vertical angle of the prism by changing the angle posture of one of the glass plates. In this way, the optical axis is corrected by the angle at which the camera shakes.

In such a liquid-encapsulated variable-angle prism, liquid is sealed between the plate glass and the bellows connecting the plate glass, so that when the angle of the slope glass is changed, the sealed liquid acts as viscous resistance, There is a disadvantage that it is difficult to follow a high-speed shake.

As a means for solving this problem, a doublet type variable apex angle prism combining a pair of spherical lenses can be considered. The principle of this variable apex angle prism will be described with reference to FIG.

A wedge-shaped prism 1 shown in FIG. 1A has a refractive index n and an apex angle α. In this wedge-shaped prism 1, a refraction angle θ is generated on an outgoing optical axis F1 with respect to an incident optical axis F. The relationship between the refraction angle θ and the vertex angle α is expressed as follows: θ = (n−1) α (1)

On the other hand, the apex angle variable prism 2 to which the present invention is applied is constituted by a pair of spherical lenses, in this example, a plano-concave spherical lens 3 and a plano-convex spherical lens 4, as shown in FIG. Are opposed to each other with a slight gap 5 kept between the spherical surfaces 3a, 4a. The refractive index n of the plano-concave lens 3 and the plano-convex lens 4 and the radii of curvature of the spherical surfaces 3a, 4a are substantially equal.

As shown by a dotted line in FIG. 1B, the apex angle variable prism 2 has a plane 3 of a plano-concave lens 3 and a plano-convex lens 4.
When b and 4b are perpendicular to the optical axis F, the light is not refracted. However, as shown by the solid line, when the plano-concave lens 3 and the plano-convex lens 4 are relatively rotated in the direction of the arrow x along the spherical surfaces 3a, 4a to form a vertex angle α between the planes 3b, 4b. Equation (1) equivalent to wedge-shaped prism 1
As a result, an output optical axis F1 with respect to the incident optical axis F is generated.

The spherical surface 3a of the plano-concave lens 3 and the plano-convex lens 4
By making the relative rotation direction along 4a a biaxial right-angle direction and freely controlling the rotation angle, the refraction direction and refraction angle θ of the output optical axis F1 can be freely changed in any direction, up, down, left and right. can do. Therefore, if the apex angle variable prism 2 is attached to a video camera body and applied to a camera shake correction device, the screen shake can be corrected.

Incidentally, the pair of spherical lenses 3 and 4 constituting the variable apex angle prism 2 must be slid without damaging each other. In this case, the lens is used as the center of rotation of each spherical lens. Instead of taking two rotation axes perpendicular to the plane passing through the center of the spherical surface and perpendicular to the lens optical axis (the optical axis of the original optical system for correcting the blur), the center of the lens spherical surface and the vicinity of the outer edge of each spherical lens are not taken. A method of setting the rotation axis on a straight line passing through one point is conceivable.

FIG. 3 is a cross-sectional view showing the guiding method, and is an example in which the optical axis of the television camera can be changed by being attached to a lens barrel (described later) of a television camera lens. In the figure, only the plano-convex lens 4 is shown for the lens support 1A and its rotation drive 1B. Plano-concave lens 3, plano-convex lens 4
The lens barrel that holds the respective supporting portions and the driving portions and is attached to the imaging lens is also omitted.

FIG. 4 is a sectional view of the lens barrel 20, and FIG. 5 is a perspective view of the lens barrel. As shown in FIG. 4, the lens barrel 20 is used to connect the variable apex angle prism 2 to the imaging lens L, and is configured as a cylindrical body having a flange 20a as shown in FIG. Flange 2
A cutout is provided at a predetermined position on the reference numeral 0a or the like for mounting the lens support 1A or the like.

As shown in FIG. 3, a plano-concave lens 3 is placed with its plane 3b facing the subject side of the camera, and a plano-convex lens 4
Is arranged to face the spherical surface 3a of the plano-concave lens 3 with the spherical surface 4a thereof with a small gap. The plane 4b of the plano-convex lens 4 is arranged close to the imaging lens L and with a gap that does not hinder the rotation of the plano-convex lens 4.

Next, the lens rotation support means will be described by taking the plano-convex lens 4 as an example.

First, the lens rotation side of the bearing 8 will be described. In FIG. 3, a steel ball 6 is placed on an imaginary rotation axis U serving as a rotation center of the plano-convex lens 4. The steel ball 6 is rotatably supported by a bearing body 17 and a bearing cover 15 to form a pivot bearing 8, which functions as a pivot point in any direction.

It is desirable to position the steel ball 6 as close as possible to the plano-convex lens 4 which is the object to be rotated, in order to reduce the overall size. The shaft 10 has one end pressed into the steel ball 6,
Further, the other end is pressed into the holding frame 11.

The holding frame 11 is fixed to the plano-convex lens 4.
That is, as shown in FIG. 4, a pair of positioning pins 12 press-fitted in the plano-convex lens 4 are fitted into holes (round hole and long hole configuration) provided in the holding frame 11, and both are positioned. The plano-convex lens 4 and the holding frame 11 are fastened by screws 13, and the plano-convex lens 4 and the holding frame 11
Are made to move together.

A pivot bearing 8 using a steel ball 6 is constructed as shown in FIGS. The bearing cover 15 is fastened to the bearing body 17 by screws 16 and the bearing cover 15
The steel ball contact surface provided on the bearing body 17 and the bearing body 17 is configured as a conical surface, so that the steel ball 6 can rotate smoothly without play. With this structure, the holding frame 11 and the plano-convex lens 4 integrally fixed to the holding frame 11 can freely rotate around the steel ball 6 as long as there is no other constraint.

The plano-convex lens 4 thus pivotally held
The rotation holding frame 11 is positioned by a pair of left and right positioning pins 19 provided on the bearing portion 8 and, in that state, is fixed to a flange 20a of a lens barrel 20 by screws 18 as shown in FIG. . FIG. 6 is a perspective view of the pivot bearing 8 and the rotation holding frame 11 as viewed from the lower front side.

Next, a driving system 1B for applying a driving force for rotating the plano-convex lens 4 will be described. FIG. 7 is a perspective view of the mechanism as viewed from the imaging lens side. The fixing portion 21 of the plano-convex lens 4 is fixed to a driving-side holding frame (drive frame) 22 of the plano-convex lens 4 by a screw 21a.

Since the drive frame 22 is restricted so as to be rotated only around the virtual rotation axis U, the arms 38 connected to the drive frame 22 are partially enlarged in FIG.
Functions as a contact surface. The contact surface 24 is a surface K (see FIG. 3) perpendicular to the rotation axis U, as is clear from FIG. The contact surface 24 is in contact with the contact portion 26. The contact portion 26 also serves as a mounting portion for the DC motor 25, and the contact portion 26 has a pair of ball bearings 52 as shown in FIG. Is provided so that the lens side rotates smoothly.

The bearing shaft 54 shown in FIG. 8 is fixed to the contact portion 26 while being pressed by the leaf spring 55 shown in FIG. As shown in FIG. 9, the bearing shaft 54 is
Are parallel to a plane K (see FIG. 3) perpendicular to the plane, and are provided radially from the center of rotation in this plane. Therefore, with this configuration, the plano-convex lens 4 is held in space by three points of the bearing 8 and the two bearings 52, and is guided along one plane perpendicular to the virtual rotation axis U. become.

Next, the driving mechanism of the plano-convex lens 4 is shown in FIG.
This will be described with reference to FIG. As shown in FIG.
The steel belt 45 is fixed to the pulley 44 attached to the motor 25 by a screw 46a via a washer so that the steel belt 45 is not slipped and is attached without being damaged. The steel belt 45 is wound around a pulley 44 of about 360 ° in a so-called α winding state, and then wound around the arm 38 of the drive frame 22 shown in FIG.

At the crossing portion of the α-winding, a hole is formed in one side of the steel belt 45, and the other 45a has a narrow width so that the steel belt 45 crosses without overlapping. A part of the steel belt 45 is fixed to the arm 38 by a screw 46b.

As shown in FIG. 10, the arm 38 of the drive frame 22
A hollow hole is formed (only the right side is shown in the figure), and a compression coil spring 47 is fitted into this hole, and a shaft 48 into which a guide 49 is press-fitted is fitted as a guide rod, thereby forming a steel belt. 45 is given a predetermined tension.

The contact portion 26 is, as shown in FIG.
It is attached via a columnar column portion 40 so as to straddle the cut-out portion of the flange 20a provided at 0.

When the motor 25 rotates in the xa or xa 'direction as shown in FIG.
The arm 38 (the drive frame 22) also rotates in this direction or the xb direction. FIG. 11 shows a state of rotation when rotated in the xa direction. When the arm 38 rotates, the plano-convex lens 4 also rotates via the drive frame 22 (see FIG. 3).

The contact portion 24 of the bearing 52 rotates along a plane K perpendicular to the rotation axis U. Therefore, the plano-convex lens 4
Is a rotation about an axis passing through the center of the convex spherical surface 4a, and even if the partial convex spherical surface 4a rotates, it does not deviate from the entire spherical surface.

FIG. 13 is a conceptual diagram intuitively explaining that the spherical surface of the plano-convex lens 4 is included in the same spherical surface before and after the movement due to such movement. A part of the spherical surface that rotates about the diameter of the sphere B does not deviate from the original spherical surface even if it moves by rotation, and the surface perpendicular to this diameter is also the same. Therefore, the spherical bearing can be rotated without deviating from the spherical surface of the sphere B by the pivot bearing 8 at one point on the diameter and guiding along the surface perpendicular to the diameter.

[0030]

When the doublet-type apex angle variable prism 2 configured as described above is applied to the correction of the optical axis of the camera shake of a television camera (video camera), the fluctuation of the optical axis (camera of the camera) is required. (Vibration) is detected separately in movements in two orthogonal directions, and if the optical axis is changed in the same direction as the respective movements, the movements can be corrected independently without being influenced by each other. From such a viewpoint, it is desirable that the direction of correction of the optical axis be a straight line when projected on a plane perpendicular to the optical axis F (z-axis) of the camera. For this purpose, the rotation of the plano-convex lens 4 needs to be a rotational movement about a straight line perpendicular to the optical axis.

However, the above-described variable apex angle prism apparatus rotates about the axis U which is not perpendicular to the optical axis as described above. For this reason, when projecting on a plane perpendicular to the optical axis, the trajectory of the movement is not a straight line but an arc.

FIG. 14 shows each plane 3 of the pair of lenses 3 and 4.
FIGS. 4A and 4B show a state in which the planes b and 4b are rotated in a plane perpendicular to the rotation axis U from a state parallel to the optical axis F and parallel to each other.
And the drive unit 1B. The plano-concave lens 3 is a sectional view parallel to the optical axis viewed from the imaging lens side, and the plano-convex lens 4 is shown by projecting the entire lens without taking a cross section. In this figure, since the plane 4b of the plano-convex lens 4 rotates in a plane perpendicular to the rotation axis U, the projection of the plane 4b on this cross section does not become a straight line but slightly tilts as shown by an arrow q. It will be the face you have.

FIG. 15 is a perspective view for explaining the degree of such inclination of the surface. The optical axis direction of the plano-convex lens 4 is the z-axis, and the rotation axis of the plano-convex lens 4 in a plane perpendicular to the z-axis. Are shown as spatial orthogonal coordinates with the direction including y as the y axis and the direction perpendicular to the yz axis as the x axis.

In this figure, a vector 101 is a normal vector (length 1) representing the initial inclination of the lens plane, and the origin of the coordinate system is the starting point. The angle formed by the straight line 103 parallel to the rotation axis passing through the origin with the z-axis is α. The normal vector 101 rotates around the straight line 103.

A normal vector 102 is a normal vector of a plane portion of the lens when the lens is rotated, and a normal vector 1
02 makes a full rotation of the circle 10
Draw 4. Here, the radius r is: r = lsinα (2)

The xz plane 105 is on the y axis and the yz plane 1
06 is a plane perpendicular to the x-axis. Hereinafter, the motion will be described by projecting a vector on the two planes 105 and 106.

First, assuming that the angle formed by the rotation of the normal vector 101 in the circle 104 is θ,
The radius of the circle 104 projected on the xz plane 105 is rsinθ as shown, and the length projected on the yz plane 106 is r
cos θ. From this, the rotated normal vector 1
Assuming that the coordinates of the end point P of 02 are (x, y, z), x = rsinθ = lsinαsinθ (3) y = r (1-cosθ) cosα = lsinαcosα (1-cosθ) (4) ) Z = lr (1-cos θ) sin α = l-lsin ² α (1-cos θ) (5)

Therefore, the rotation angle φ in the projection of the normal vector 102 onto the xz plane is as follows.

[0039]

(Equation 1)

The rotation angle ψ in the projection on the yz plane is as follows.

[0041]

(Equation 2)

Of these, the angle φ is the rotation angle in the intended direction, and the angle ψ is the error component. Here, when the angle α between the optical axis and the rotation axis 103 is set to 15 °, φ and 計算 are calculated and represented in a graph as shown in FIG.

As is clear from this, when φ is small,
For example, when φ = 1 °, the rotation angle 垂直 in a direction perpendicular to this is ψ ≒ 0.0326 °, and an erroneous shake (about 0.33%) may occur in the y direction due to the correction in the x direction. I understand.

As described above, when the variable apex angle prism device is employed, the lens has a small resistance when rotating, and can be smoothly swung. A motion component in a different direction is generated, which causes a problem that image blur is newly generated in a direction orthogonal to the direction in which the blur is taken.

Therefore, the present invention is to solve such a conventional problem, in which the other spherical lens is rotated so as to cancel the error component.

[0046]

In the apex angle variable prism apparatus according to the present invention for solving the above-mentioned problems, first and second spherical lenses having spherical surfaces having substantially the same radius are opposed to each other. Combination, a device having a vertex angle variable prism that is rotated around a straight line connecting one substantially spherical center and the vicinity of the lens outer edge, the optical axis is the z axis,
The direction in which the rotation axis of the first spherical lens intersects with the plane extending along the optical axis in a plane perpendicular to the optical axis is the y-axis, and the rotation axis of the second spherical lens intersects with the plane extending along the optical axis in the same plane. Assuming that the direction is the x axis, the rotation angles in the yz plane of the first spherical lens and the xz plane of the second spherical lens are detected, and the rotation angles in the xz plane of the second spherical lens are detected by the angles. And the rotation angle of the first spherical lens in the yz plane is corrected.

According to a third aspect of the present invention, the first and second spherical lenses having spherical surfaces of substantially the same radius are combined with their spherical surfaces facing each other, and the center of one approximately spherical surface and the outer edge of the lens are formed. An apex angle variable prism device that rotates around a straight line connecting the vicinity is attached to the front surface of the optical system of the imaging device, and the imaging device detects shake in two directions orthogonal to the optical axis. When a rotation angle of the first or second spherical lens is adjusted based on an output from the shake detection sensor, the second or first spherical surface is used by using an output of the shake detection sensor. The rotation angle of the lens is corrected.

In the present invention, the correction is performed by rotating the other lens so that an error component generated when one of the lenses is rotated can be canceled. By doing so, even if the optical axis of the lens is changed using the straight line connecting the center of the spherical surface of the lens and one point of the outer edge of the lens as the rotation axis, the apex angle of the variable prism can be changed by a predetermined angle. as a result,
Camera shake correction can also be performed correctly.

As described above, it is possible to cancel the shake in the other direction caused by the fact that the rotation axis of the correction lens is not perpendicular to the optical axis of the system and perpendicular to each other.

[0050]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of a variable apex angle prism apparatus according to the present invention and an image stabilizing apparatus using the same will be described in detail with reference to the drawings when applied to the above-described variable apex angle prism apparatus. Will be described.

FIG. 1 is a system diagram of a main part showing an embodiment when the present invention is applied to the case where the camera shake correction of a television camera is performed by using the above-described apex angle variable prism 2.

A variable apex angle prism 2 having a configuration shown in FIG. Therefore, the plano-concave lens 3 and the plano-convex lens 4 can freely rotate in two axial directions orthogonal to the optical axis. Assuming that the two orthogonal axes are a horizontal axis x which is a horizontal scanning direction and a vertical axis y which is a vertical scanning direction, when the plano-concave lens 3 is rotated in the horizontal direction, the plano-convex lens 4 is rotated in the vertical direction and the optical axis Is corrected.

In FIG. 1, a subject image is formed on a CCD 202 in this example, which is an image pickup device, via a variable apex angle prism 2 and an image pickup lens 201 and converted into a signal.
The image signal is subjected to predetermined signal processing by a camera signal processing circuit 230 at the subsequent stage to generate a video signal.

The camera body, in this example, the imaging lens 201, the angular velocity sensors 203, 20 which are the shake detection sensors
4 is attached. The sensor 203 detects a vertical shake (shake in the yz plane 106 in FIG. 15), and the sensor 204 detects a horizontal shake (shake in the xz plane 105 in FIG. 15).

Each detection signal (x and y signals for convenience) is amplified by the amplifiers 205 and 206, and then supplied to the filter 207 to pass only the band of the hand vibration component to be removed. A filter 207 is provided for each of the x and y signals, but is omitted in the figure.

Thereafter, A in the microcomputer 209
/ D converter 231. The digitized angular velocity signals x and y are integrated by the integrator 232 and smoothed, and then the integrated signal (signal corresponding to the rotation angle) φL
x and φLy are Y axis operation means 233 and X axis operation means 234
Correction signal S which is supplied to the lens and corrects the attitude of the lenses 3 and 4
It is converted to x and Sy. These signals Sx and Sy are the target values for which the shake is to be corrected. Above variable angle prism 2
Is not necessarily in the initial state (the initial position in which neither of them is rotated), but may be inclined in the x and y directions. Therefore, in the present invention, the inclination angle sensors 210 and 211 for sensing the attitude of the pair of lenses 3 and 4 are provided in association with the lenses 3 and 4. In this example, a detection light beam is incident substantially perpendicular to the lens planes 3b and 4b, and the position of the reflected light beam is determined by PS.
The tilt state of the lenses 3 and 4 is detected by detecting with a D sensor (Position Sensitive Ditector).

In particular, an area type PS is used as an inclination angle sensor.
If D is used, a single sensor can detect inclination (falling) in both the x and y directions. Sense outputs from the inclination angle sensors 210 and 211 are output to signal processing circuits 212, 213, 214 and 2 respectively.
15 and output as sense components in the x-axis and y-axis directions, respectively. The sense outputs (tilt signals) of the lenses 3 and 4 in the x-axis direction are represented by φxx and φyx. Similarly,
The sense outputs of the lenses 3 and 4 in the y-axis direction are φxy, φyy
Expressed by

These inclination signals are supplied to the amplifiers 241 to 244.
Are converted into digital signals by A / D converters 235 to 238 in the microcomputer 209 via the microcomputer 209, and the x-axis components and the y-axis components correspond to each other.
The signals are supplied to the lenses 3 and 234 and are calculated and output as signals for correcting the optical axes of the lenses 3 and 4.

The arithmetic processing by the arithmetic means 233 and 234 is as follows: Sx = φx = φLx + φyx−φxx (8) Sy = φy = φLy + φxy-φyy (9)

A supplementary explanation of these equations will be given. First, when both the lenses 3 and 4 are at the initial position (the state in which the rotation of the lenses is not corrected at all), φxx = φxy = φyy = φyx = 0 (10). At this time, for example, when the camera body shakes in the x-axis direction due to camera shake, an integrated signal φLx related to the sensor 203 is obtained, and an optical axis correction signal Sx for correcting this is generated.

The rotation of the lens 3 is controlled by the optical axis correction signal Sx. The rotation of the lens 3 causes the lens 3 to tilt, and a tilt signal that is not originally required, that is, an error component φ due to the lens rotation.
xy occurs. In order to cancel the tilt signal φxy, which is the error component, the lens 4 is rotated by adding it to the other lens 4. That is, Sy = φxy (11).

Therefore, when the lens 4 is already tilted (φyy ≠ 0), the lens 4 may be corrected by the difference Sy = φxy−φyy (12). When there is camera shake also in the y-axis direction, the integrated signal φLy related to the sensor 204 has been obtained, so that the optical axis correction signal Sy finally applied to the lens 4 is Sy = φLy + φxy−φyy. (13) The above equation can be derived for the lens 3 by the same concept.

The outputted optical axis correction signals Sx and Sy are converted into voltages by D / A converters 216 and 217 and amplified by amplifiers 218 and 219, respectively. , 221.

That is, rotation angle control is performed such that φLy + φxy = φyy (14) φLx + φyx = φxx (15)

Therefore, a motion component in a direction different from the intended direction is generated at the time of rotation, so that it is possible to avoid a new blur of the image in a direction orthogonal to the direction in which the blur is taken.

[0066]

As described above, according to the present invention, when using a doublet type apex angle variable prism in which a pair of spherical lenses are combined, one point on the outer edge of the lens in a direction perpendicular to the optical axis and orthogonal to each other. When the system is configured to guide the axis passing through the lens and the center of the lens as the rotation axis, the rotation of the lens occurs, that is, the other direction occurs because the lens rotation axis is not perpendicular to the optical axis of the system and is not orthogonal to each other. In this case, the occurrence of the runout can be electrically canceled.

According to this, when the apex angle of the prism is varied by taking the lens rotation axis on a straight line connecting the center of the lens spherical surface and the outer edge of the lens, the effect of image blurring due to a motion component in a direction different from the intended direction is obtained. It has features that can be deterred.

If the apex angle variable prism is mounted on an optical system of a video camera so that the apex angle of the prism can be varied based on a camera shake component, appropriate camera shake correction can be realized.

Of course, the variable prism can be miniaturized by selecting the rotation axis of the lens in this way. Therefore, the present invention is very suitable for application to the optical system of a portable video camera used for business or consumer use. is there.

[Brief description of the drawings]

FIG. 1 is a system diagram of a main part showing an embodiment of an imaging device to which a variable apex angle prism according to the present invention is applied.

FIG. 2 is an explanatory diagram of a variable apex angle prism.

FIG. 3 is a cross-sectional view illustrating a relationship between a lens supporting unit and a driving unit.

FIG. 4 is a partial cross-sectional view showing a state in which a lens is attached to a lens barrel.

FIG. 5 is a perspective view showing a schematic shape of a lens barrel.

FIG. 6 is a perspective view of a main part showing details of a lens support unit.

FIG. 7 is a perspective view illustrating an example of a lens driving unit.

FIG. 8 is a cross-sectional view of a main part showing details of a lens driving unit.

FIG. 9 is an exploded perspective view showing an example of a motor transmission system.

FIG. 10 is a front view (part 1) in which a part of an example of a motor transmission system is sectioned;

FIG. 11 is a front view (part 2) showing a cross section of a part of an example of a motor transmission system.

FIG. 12 is a perspective view showing a state where the variable apex angle prism is assembled.

FIG. 13 is an explanatory diagram showing a rotating state of a plano-convex lens.

FIG. 14 is a partial cross-sectional view showing the occurrence of rotational displacement.

FIG. 15 is a diagram showing a rotating coordinate system for explaining rotation displacement.

FIG. 16 is a characteristic diagram showing a rotation shift amount.

[Explanation of symbols]

2 ... vertical angle variable prism, 3,4 ... spherical lens,
1A: lens support, 1B: lens drive, 6
... Steel ball, 25 ... Motor, 45 ... Belt, 2
02: CCD, 203, 204: angular velocity sensor, 210, 211: inclination angle sensor, 209:
Microcomputer, 220, 221 ... motor, 230 ...
Signal processing circuit, 233, 234... Arithmetic means for generating optical axis correction signal

Claims (6)

[Claims] 1. A first and a second spherical lens having spherical surfaces of substantially the same radius are combined with their spherical surfaces facing each other, and are rotated about a straight line connecting the center of one approximately spherical surface and the vicinity of the outer edge of the lens. An apparatus having a variable apex angle prism, wherein the optical axis is the z-axis, the direction in which the rotation axis of the first spherical lens intersects with the plane extending along the optical axis in a plane perpendicular to the optical axis is the y-axis, and in the same plane. When the direction in which the rotation axis of the second spherical lens intersects with the plane formed by the optical axis is defined as the x-axis, the rotation angle in the yz plane of the first spherical lens and the rotation angle in the xz plane of the second spherical lens The variable apex angle prism device, wherein the rotation angle of the second spherical lens in the xz plane and the rotation angle of the first spherical lens in the yz plane are corrected by the detected angles. . 2. The apex angle variable prism device according to claim 1, wherein said first spherical lens is a plano-concave spherical lens, and said second spherical lens is a plano-convex spherical lens. 3. A first and a second spherical lens having spherical surfaces having substantially the same radius are combined with their spherical surfaces facing each other, and are rotated about a straight line connecting the center of one of the spherical surfaces and the vicinity of the outer edge of the lens. A variable apex angle prism device is attached to the front of the optical system of the imaging device, and a shake detection sensor for detecting shake in two orthogonal directions to the optical axis is attached to the image pickup device. When the rotation angle of the first or second spherical lens is adjusted based on the rotation angle, the rotation angle of the second or first spherical lens is corrected using the output of the shake detection sensor. Characteristic shake correction device. 4. The apparatus according to claim 3, wherein the first spherical lens is a plano-concave spherical lens, and the second spherical lens is a plano-convex spherical lens. 5. The optical axis is the z-axis, the y-axis is the direction in which the rotation axis of the first spherical lens intersects with the plane extending along the optical axis in a plane perpendicular to the optical axis, and the second spherical lens is in the same plane. When the direction in which the rotation axis of the optical axis and the plane of the optical axis intersect is defined as the x-axis, the shake detection sensor detects the y of the first spherical lens.
The rotation angles of the second spherical lens in the xz plane and the rotation angles of the second spherical lens in the xz plane and the rotation angles of the first spherical lens in the yz plane are detected. 4. The image stabilizing apparatus according to claim 3, wherein the correction is performed. 6. The shake correction apparatus according to claim 3, wherein an angular velocity detection sensor or an acceleration detection sensor is used as the shake detection sensor.