JP2752115B2 - Image displacement device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an image displacement device for moving an image, which is used for prevention of image blur in a camera, an optical device, or the like.

(Prior Art) The following describes an example in which the present invention is applied to a camera.

When a photographer takes a picture while supporting the camera with his / her hand, the camera often generates a small amount of vibration, which is caused by so-called camera shake in relation to a shutter speed or the like. It is known that image degradation is caused. Therefore, various proposals have conventionally been made with one of the problems to be solved in this type of camera is to eliminate the deterioration of the captured image due to the camera shake.

 Hereinafter, an apparatus for this purpose is referred to as an "image blur prevention apparatus".

The image blur prevention device is generally a vibration detecting means for detecting a vibration generated in the camera, and a correction of an image position in which the image blur generated by the vibration can be corrected by, for example, moving a lens of a photographing optical system. Means (means for apparently stopping the image), and drive control means for driving the means for correcting the image position in accordance with the detection signal from the vibration detecting means. For the position correcting means, for example, a correction optical system (for example, a lens) for correcting image blur is moved in a liquid,
A mechanical drive system that keeps the apparent image stationary by rotating the angle of the mirror in the shooting optical path, and a CCD (Charge coupled device) as an imaging device
An electric drive system (for example, Japanese Patent Laid-Open No. 60-143330) has been proposed in which the photographing area is vibratedly changed in accordance with the movement of the image blur to thereby correct the image blur.

FIG. 13 schematically shows an example of the configuration of a conventional example provided with such an image blur prevention device. In a camera, information for detection and correction of image blur, that is, camera shake information, usually exists in two directions, a vertical direction and a horizontal direction. It is necessary to prevent image blur separately for each,
Since the principles of image blur prevention against vibration can be considered to be the same and independent of each other, the following description will be limited to vertical vibration for convenience.

In FIG. 13 described above, reference numeral 101 denotes an acceleration sensor mounted on a camera (not shown), and a rotation direction (for example, the front part of the camera swings up and down) in a plane parallel to the plane of the drawing.
Detect changes in angular acceleration of vibration.

Reference numeral 102 denotes an integrator, which converts the angular acceleration of the in-paper rotation detected by the acceleration sensor 101 into an angular velocity. In this conventional example, an output signal from the integrator 102 is input to an actuator 119 which is a speed input type image position correcting means via an analog switch 118 described later. Here, the analog switch 118 is capable of switching between two circuit states, and one of them is a feedback system that constantly maintains the radial position of the correction lens 113 in the actuator 119 at the center position. Another switching position is a switching position at which the signal from the integrator 102 is introduced into the actuator 119 to prevent image blur. These are switched in a timely manner by a signal 120 from the control CPU 130 in FIG. It should be noted that the rotation angle due to the shake described here is very small, and the rotation speed and the shake speed may be considered to be approximately equal.

Reference numeral 113 in FIG. 13 denotes a correction lens located in the optical path of the photographing optical system, and a spring 112 connected to the correction lens.
A magnet 111 fixed to the correction lens loosely fitted to the coil 110 is supported in a lens barrel (not shown) so as to be movable in the vertical direction in FIG. That is, a downward spring force is applied to the correction lens 113 by the spring 112,
The position of the correction lens 113 is determined by the balance between this and the driving force due to the magnetic action acting on the magnet 111 integrated with the correction lens 113 when the coil 110 is energized. These elements constitute an image position correcting means for correcting the position of the projected image on the screen.

The driving force due to the magnetic action from the coil 110 is determined by the control current supplied to the coil 110.
The above-described switching of the analog switch 118 results in one of the following two states. That is, one is the control current when the correction lens 113 is maintained at the center position (the center position within the range in which the correction lens 113 can move) when a feedback system circuit is configured,
The other is a correction lens 113 based on a signal from the integrator 102.
Is a control current in a state where a circuit of an image blur prevention system is formed when the image is moved to prevent image blur.
Which of these states will depend on the switching of the analog switch 118 as described above.

In the example of FIG. 13, the feedback system circuit includes a potentiometer 109 that detects a value at a position corresponding to the amount of movement of the correction lens 113 as a voltage (the output voltage is zero at a neutral position), Subtractor 1 with as input signal
08, 106 and a differentiator 107, for example, a subtractor 1
When a positive voltage is input to the positive input terminal 06, the correction lens 113 is moved upward in FIG. 13 at a speed corresponding to the voltage value, and a negative voltage is input to the positive input terminal. In this case, the correction lens 113 is moved downward at a speed corresponding to the voltage value. Therefore, when this feedback system circuit is established (when the analog switch 118 is switched in the opposite direction as shown), the correction lens 113 always tries to return to the center position autonomously.

The analog switch 118 is connected to the control CPU 130 of the camera shown in FIG.
According to the lens position control signal 120 output from T120, when the signal 120 is `` Lo '', the selection switch 118 is switched to a switching state in which the signal from the subtractor 108 is input to the subtractor 106. When the signal 120 is "Hi", the selection switch 118 is switched to a state where the signal from the integrator 102 is input to the subtractor 106 (the state shown in FIG. 13). The switching of the output (Lo, Hi) from the output unit OUT120 of the control CPU 130 of this camera is based on the assumption that the camera of the conventional example is a camera having an automatic photometry (AE) and an automatic focus (AF) function. In this case, the shutter release buttons SW1 and SW2 are operated in accordance with the normal photographing operation, so that the shutter release buttons SW1 and SW2 are provided at the timing described in the flowchart of FIG. Note that the release buttons SW1 and SW2 are turned on and off, and the lens position control signal 120 is set to “Hi” or “L”.
The relationship between the switching state of “o” and the position of the correction lens 113 is shown in FIGS.

An outline of the operation of the image blur prevention apparatus having the above configuration will be described. As described above, the camera control CPU 130 detects the operation (ON) corresponding to the shutter release buttons SW1 and SW2 by the input units IN1 and IN2. And an output section OUT120 for the lens position control signal 120. A publicly-known photometric circuit 140 and a distance measuring circuit 141 are connected as external information input stages. When the power of the camera (not shown) is turned on, a lens position control signal 120 is output at the next timing according to the flowchart shown in FIG.

That is, first, when the power is turned on, the lens position control signal 120 becomes “Lo”, and this state is continued until SW1 is turned on. This is a stage before the photographing operation is started, and therefore, the correction lens 113 of the image blur prevention device is maintained at the neutral position. That is, the lens position control signal 120 is "Lo" and the analog switch 118 is switched from the state shown in FIG. 13, so that the polarity of the lens position signal detected by the potentiometer 109 is inverted by the subtractor 108 and the speed input is performed. Input to the actuator 119 of
A feedback circuit that always returns the correction lens position 113 to the center position is configured.

Next, holding the camera for shooting, pointing the camera at the subject to be shot and pressing the release button SW1, predetermined AE, AF operation is performed, and the control CPU 130 of the camera shown in FIG. Lens position control signal 12
Set 0 to "Hi" (see Fig. 16).

Due to the above, the lens position control signal 120 is "Hi"
Then, the analog switch 118 shown in FIG. 13 is switched to input the output of the integrator 102 to the actuator 119, and the correction lens 113 apparently stops the image on the photographing screen (film surface). (See the figure of the lens position in the upper part of FIG. 16). The viewfinder image that the photographer is looking at for photographing is also apparently stopped by the vibration of the correction lens.

Next, when the release switch SW2 is turned on, in the conventional example, the control CPU 130 is controlled for a predetermined period of time (time T in FIG. 17) as shown in FIG.
Switches the lens position control signal 120 to "Lo",
The input to the actuator 119 is again used as a signal from the subtractor 108 of the feedback system, and the correction lens 113 is returned to the neutral position. In the meantime, the release preparation operation such as adjustment of the aperture f of the camera and setting of the shutter speed is completed based on the signal information from the photometry circuit 140 and the distance measurement circuit 141 described above.

Then, after the predetermined time T has elapsed, the lens position control signal 120 is returned to “Hi” again.
The release operation is performed by holding the correction lens 113 in an oscillating movement state in which an image on the projection surface (film surface) is apparently stopped. In this state, the projected image is apparently kept still, so that even if there is vibration due to camera shake, shooting without blurring can be performed.

In the operation of the image blur prevention apparatus as described above, the formation of the feedback system for returning the correction lens 113 to the neutral position is performed immediately before the release preparation state at the time of shooting is completed. It depends on the reason.

That is, since the correction lens 113 is supported in the lens barrel, the movable range (the range of ± D in FIG. 17) in which the correction lens 113 can be moved in a direction perpendicular to the photographing optical axis is too large due to the structure of the camera. Usually it is not possible. For this reason, if the correction lens is too close to one side during shooting, the correction for preventing camera shake, that is, the movement of the correction lens 113 for correcting image blur, may be limited in the biased direction. Therefore, in order to solve such a problem and secure the amount of movement of the correction lens in an appropriate direction,
The entire system was designed to return the correction lens to the neutral position just before the actual shooting operation release.

(Problems to be Solved by the Invention) In the above-described image blur preventing apparatus, the image blur is prevented by, for example, apparently stopping the projected image on the film at the time of photographing. Like
It is possible to provide a sufficient tolerance for the movement of the correction lens required to move the correction lens, which is a part of the photographing optical system, in a direction perpendicular to the photographing optical axis (oscillating movement corresponding to camera shake). desired.

However, giving a large allowable range of the movement of the correction lens as described above is restricted from the viewpoint of the structure of the camera, and setting a large allowable range of the movement requires a camera that obtains high-quality images. Is not necessarily consistent with the purpose of Rather, from these viewpoints, it is desirable that the allowable range of movement of the correction lens be set as small as possible. However, setting the allowable movement range of the correction lens to be small means that the correction lens reaches the field of the allowable movement range (range of ± D), as can be seen from, for example, the figure of the lens position in the upper part of FIG. (A portion in the drawing), there may be cases where it is impossible to actually perform effective image blur prevention control.

The present invention has been made in view of the above-described circumstances, and has an image displacement that can perform a wide-range displacement operation by effectively using a movable region of an image displacement unit that displaces an image on an imaging surface. It is intended to provide a device.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides an image moving apparatus for displacing an image on an image forming surface by moving an image displacing means. Setting means for setting the means to the movement start initial position; and changing means for changing the movement start initial position set by the setting means.

(Examples) Hereinafter, the present invention will be described based on examples shown in the drawings.

Embodiment 1 FIGS. 1 to 4 illustrate a first embodiment of an image blur prevention device for a camera according to the present invention.

FIG. 1 shows an outline of the entire circuit of the device, and the basic configuration is the same as that of the circuit described in FIG. 13 except for a part, thus facilitating understanding. For this reason, parts having common features are denoted by the reference numbers obtained by subtracting 100 from the reference numbers assigned to the parts in FIG.

In FIG. 1, reference numeral 1 denotes an angular acceleration sensor mounted on a camera (not shown), which detects a change in angular acceleration due to rotational vibration (for example, vibration in which the front part of the camera swings vertically) in a plane parallel to the paper surface. It has become. A separate sensor is provided for detecting the vibration in the plane perpendicular to the optical axis and the plane of the paper (actually, in the horizontal direction), but is omitted for convenience in the description of this example. An integrator 2 integrates the angular acceleration detected by the angular acceleration sensor 1 into an angular velocity.

7 is a differentiator, 9 is a potentiometer, 10 is a coil,
11 is a magnet integrated with the correction lens, 12 is a spring for pressing the correction lens in the downward direction in the figure, 13 is a correction lens, and a magnetic action generated in the magnet by energizing the coil 10 by these and the subtractor 6. The actuator 19 as an image position correcting means for positioning the correction lens in the vertical direction in the figure by the balance of the pressing force of the spring and the spring, and this structure is the same as the example of FIG. 13 already described. .

The control current supplied to the coil 10 is determined by the switching state of the first analog switch 18 and the second analog switch 16 described below.

Reference numeral 18 denotes a first analog switch, which is operated in accordance with a lens position control signal 20 (hereinafter sometimes simply referred to as a signal 20) from a camera control CPU 30 shown in FIG. The state in which the signal from 16 is input to the subtractor 6 of the actuator 19 and the mode in which the signal from the subtractor 8 is input to the subtractor 6 of the actuator 19 can be switched in a timely manner. .

That is, when the lens position control signal 20 is "Lo", the first analog switch 18 enters a state in which a signal from the subtractor 8 is input to the subtractor 6, and the correction lens 13 is maintained at the center position. Thus, a feedback circuit for controlling the actuator 19 is formed.

On the other hand, when the signal 20 is "Hi", the signal from the second analog switch 16 is input to the subtractor 6. Therefore, in this case, depending on the switching state of the second analog switch 16, the drive of the actuator 19 is controlled to prevent the image blur, or the correction lens 13 is moved in the same direction as the image vibration due to the detection vibration of the camera. The actuator 19 is controlled to be moved to give the initial position of the correction lens at the start of image blur prevention.

The second analog switch 16 controls the camera
A mode in which a signal from the integrator 2 is directly input to the subtracter 6 (via the first analog switch 18) by a drive reverse signal 21 (hereinafter sometimes simply referred to as a signal 21) from the CPU 30; The mode of inverting the sign of the signal through the subtractor 3 and inputting it to the subtractor 6 (via the first analog switch 18) can be switched as appropriate.

That is, assuming that the first analog switch 18 is in the state shown in the figure, the signal of the drive reverse rotation signal 21 is "Hi".
At this time, the second analog switch 16 is in the state shown in the figure, and the signal from the integrator 2 is input to the actuator 19, so that the whole system of the present apparatus is controlled for image blur prevention. On the other hand, when the signal 21 is "Lo", the second
Analog switch 16 is switched to a state (not shown),
The sign of the signal from the integrator 2 is inverted and input to the subtracter 6, and the entire system of this apparatus performs a control operation completely opposite to that of image blur prevention. That is, when viewed from the image on the screen, apparently, image blur is amplified and the image vibrates.

FIG. 2 shows a control CPU 30 for outputting the signals 20 and 21.
Part of the shutter release button.
Input sections IN1 and IN2 for detecting the ON state of SW1 and SW2, and signal 2
It has output sections OUT20 and OUT21 for outputting 0 and 21, and further receives signals from an automatic photometric circuit (AE) and an automatic ranging circuit (AF).

The control CPU 30 receives signals from the shutter release buttons SW1, SW2 and the AE and AF circuits and operates according to the flowchart shown in FIG.
20, 21 are output at a predetermined timing.

Hereinafter, an outline of the operation of the image blur prevention apparatus of this embodiment will be described with reference to the flowchart of FIG.

First, when the power is turned on, the lens position control signal 20 is set to “Lo” (# 01), and the drive reverse rotation signal 21 is set to “Hi”.
Then, this state is continued until the release button SW1 is turned on (# 03).

This is a stage before the shooting operation is started, and the correction lens 13 of the image blur prevention device is maintained at the center position. That is, since the lens position control signal 20 is "Lo" and the drive reversal signal 21 is "Hi", the first analog switch 16 is in the opposite state to that of FIG. The polarity of the correction lens position signal is input to the actuator 19 after being inverted by the subtractor 8, and feedback control is performed to always return the correction lens 13 to the center position.

Next, when the user holds the camera for shooting and points the camera at the subject to be shot and presses the release button SW1, predetermined AE and AF operations are performed, and the camera control CPU 30 shown in FIG. Is the lens position control signal 2
0 is set to "Hi" as shown in FIG. 4 (# 04, # 05).

When the lens position control signal 20 becomes "Hi", the analog switch 18 is switched to input the output of the integrator 2 to the actuator 19 without any change.
Since the input signal to the analog switch 16, that is, the drive reversal signal 21 remains “Hi”, the drive control for the correction lens 13 is set to a control state in which an image on the photographing screen (film surface) is apparently stopped. . By the image blur prevention control of the correction lens, the finder image that the photographer is looking at for photographing is also apparently stopped.

Next, when the release switch SW2 is turned on while the release switch SW1 is kept on (# 06, # 07), the control CPU 30 sets the lens position control signal 20 to "L".
o "(# 08), and when the signal from the subtractor 8 is input to the actuator 19, the operation of the system is returned to the state of the above-mentioned feedback control, so that the control lens 13 attempts to return to the center position again. Placed in state. In the meantime, based on the signal information from the photometry circuit 40 and the distance measurement circuit 41, the release preparation operation such as adjustment of the aperture value of the camera and setting of the shutter speed is completed as shown in FIG. (# 09, # 10).

After the completion of the release preparation operation, the lens position control signal 20 is returned to "Hi"(# 12), and at the same time, the drive reverse rotation signal 21 is switched to "Lo" for a predetermined short fixed time Δt (# 13). , # 14, # 15), the shutter operation is performed (# 16), and the process returns to # 01.

As a result, the inverted signal from the integrator 2 is input to the actuator 19, and the
Is moved in the forward direction with respect to the vibration direction of the image, completely opposite to the control operation for preventing the image blur. In other words, in the uppermost diagram in FIG. 5, the horizontal axis indicates the center position.
Is required to be moved downward from the horizontal axis, the drive reversal signal 21 during the Δt time as described above.
Is input to the actuator 19, the correction lens 13
Will be moved upward from the horizontal axis. Needless to say, the moving direction of the correction lens is determined by the direction of the vibration generated in the camera.

After the lapse of the predetermined time Δt, the drive reverse rotation signal 21 is returned to “Hi”. At this time, the position of the correction lens 13 has been moved slightly upward from the horizontal axis as shown in the uppermost diagram in FIG. 5, and this is the point in time when the operation of the correction lens 13 to start image blur prevention is started. Is the initial position IP of the correction lens 13.

When the drive reversal signal 21 returns to "Hi", the first analog switch 16 is in the state shown in FIG. 1, and the actuator 19 is in a state where the signal from the integrator 2 is directly input to the system. The whole is in an image blur prevention control state. Therefore, the correction lens 13 is moved from the initial position IP (the position slightly moved upward from the horizontal axis) shown in the uppermost diagram in FIG. 5 to prevent image blurring (moves downward in this example). Start the projection plane (film surface) of the captured image
While the shutter is open during the release operation, the captured image is apparently kept still, and even if there is vibration due to camera shake, It is possible to take pictures without any problems.

In this example, the output time of the drive reverse rotation signal 21 immediately before the release operation is set to 1/1 / the shutter open time as shown in the figure.
2 and set the correction lens 1 with the expected vibration.
3 is driving across the center position.

According to such a configuration, for example, when the neutral position, which is the horizontal axis in FIG. 5, is set as the initial position of the start of the image blur prevention operation, and the vibration for preventing the image blur is performed in an area divided into two above and below it. 5, the initial position at which the image blur prevention operation is started is deviated by l in FIG. 5, and there is an advantage that the stroke range in which the image blur prevention can be performed is increased.

Embodiment 2 The present embodiment shown in FIG. 6 and FIG.
When the second analog switch 16 inverts the sign of the signal of the integrator 2 and inputs the inverted signal to the subtractor 6 of the actuator 19, the inverted signal is amplified by the amplifier 22 and the input of the inverted signal is performed. The time Δt ′ is shorter than the fixed time Δt of the first embodiment, and the other configuration is the same as that of the first embodiment. Also, the control flowchart can be used in the same manner except that the calculation of the fixed time Δt in FIG. 4 of the first embodiment is changed to the calculation of Δt ′.

Here, for example, the amplification factor of the amplifier is doubled, and the fixed time Δt ′ is set to / 4 of the shutter open time t _open ,
A preferred example is a case where the initial position of the correction lens 13 is approximately half of the displacement of the correction lens when the shutter is opened, but such a relationship is generally such that the correction lens is moved in the opposite direction to the image blur prevention. , And the amplification factor K by the above-mentioned amplifier, It should be decided so that.

The above description assumes that the speed of camera shake vibration during shutter opening is constant. However, the normal camera shake frequency (0.1 to 5 Hz) and the shutter opening time of about 1/60 which is usually used In consideration of the above, the above conditions are well matched.

According to the second embodiment, compared to the first embodiment, there is an advantage that the actual opening of the shutter after the pressing operation of the shutter release button can be promptly performed.

Third Embodiment The third embodiment described with reference to FIGS. 8 and 9 shows an example in which the configuration of a control system is simplified.

To explain the configuration of this embodiment, a potentiometer 9, a coil 10, a magnet 11 integrated with a correction lens 13, a spring 12 for pressing the correction lens 13 downward in the figure, and a subtractor 6 for energizing the coil 10. Actuator 24 composed of
A servo-driven image position correcting means for positioning the correction lens 13 in the vertical direction in the figure by the balance between the magnetic action generated by the magnet and the pressing force of the spring is provided.
Except that the differentiator 7 is not included, it is the same as the example of the first embodiment already described. Potentiometer 9 is a correction lens
The connection is made so that zero is output when 13 is in the center position, a positive signal is output above, and a negative signal is output below. Therefore, the correction lens 13 moves in proportion to the vertical center position as the origin by the voltage of the + input terminal of the subtractor 6.

The feature of the present embodiment is that an integrator 23 is provided between the analog switch 16 and the subtractor 6, and this integrator 23 outputs the lens position control signal 20 from the control unit CPU 30 as "L".
The signal 20 is provided so as to be a reset input signal so that the signal is cleared when "o" is reached and the output is set to 0 (zero).

That is, the switching of the analog switch 16 is controlled by the drive reverse signal 21 from the control unit CPU 30. When the drive reverse signal 21 is “Lo”, the output of the subtracter 3 is output to the integrator 23. When the drive reverse signal 21 is “Hi”, the output of the integrator 2 is input to the input terminal of the integrator 23. The output timings of the signals 20 and 21 are the same as those in the first embodiment, and these timing signals can be sent out by a known camera control IC.

The operation of the anti-shake device having the above configuration will be described. The timing relationship of this operation is shown in FIG. 9. First, at t <0 before the illustrated shutter release button is pressed, the signals 20, 21 are set. Are both “Hi”, the angular acceleration signal detected by the angular acceleration sensor 1 is converted into an angular velocity signal by the integrator 2,
And converted into an angle signal.

The angle signal from the integrator 3 is input to the actuator 24, and the correction lens 13 is controlled so as to prevent image blur.

When a shutter release button (not shown) is pressed,
As shown in FIG. 9, the signal 20 is "L" for a certain period of time.
o ", the integrator 23 is reset as described above, and its output becomes 0 (zero). As a result, the actuator 24 pulls the correction lens 13 back to the center position of the moving range and stops.

After the elapse of the predetermined time, the signal 20 is set to "Hi" again, and at the same time, the signal 21 is set to "Lo" for a short time Δt. Accordingly, the analog switch 16 is switched from the state shown in the figure, and the signal from the subtractor 3 is input to the integrator 23. The correction lens 13 is moved in the forward direction with respect to the detected vibration. When the time Δt has elapsed, the movement of the correction lens 13 in the same forward direction ends, and the position becomes the initial position on the photographed image plane of the projected image at the start of the image blur prevention control operation.

After the elapse of the time Δt, the signal 21 returns to “Hi”, so that the whole system is in the image blur prevention control state. That is, in this state, the signal from the integrator 2 (that is, the vibration signal of the detected camera shake) is input to the integrator 23 through the analog switch 16, and this integrator 23
At 23, a camera shake angle signal is input to the actuator 24, and the camera enters a control state in which the correction lens 13 is moved to prevent image blur, and the projected image on the photographing screen is apparently stopped. In this state, the shutter is opened, and this state is continued for the shutter open time t _open , so that blur-free shooting is performed. The correction lens is a position control, and the detected camera shake is a signal corresponding to an angle, but a minute angle variation such as camera shake can be performed without any problem by considering that both are approximately equal.

Here, the above-mentioned time Δt for determining the image initial position
And the length of the shutter open time t _open is
What is necessary is just to carry out similarly to Example 1 or 2 mentioned above.

Note that the voltage range in which the integrator 23 can integrate may be set to be equal to the lens driving range of the actuator 24 that is a lens driving device.

According to such a configuration, there is an advantage that the configuration of the control system for driving the lens to correct the position of the projection image on the photographing screen is simplified.

Embodiment 4 In the present embodiment shown in FIGS. 10 to 12, the image blur prevention device is applied to an electronic still camera, and the image is degraded due to the vibration due to the vibration in the rotation direction (rolling direction) around the photographing optical axis. This is an example of a case in which this is prevented.

In FIG. 10, reference numeral 53 denotes an imaging unit, and a rotation driving unit 51c
Is provided so that it can be driven to rotate in a plane parallel to the plane of the drawing. 52c is a rotation drive control circuit,
In accordance with a rotation drive signal 56 input from the control circuit of FIG. 11, the image pickup unit 53 is rotated so as to have a rotation angle corresponding to the signal.

The control circuit shown in FIG. 11 detects an angular accelerometer 61 for detecting the rotational vibration (vibration in the rolling direction) of the photographing apparatus equipped with the image pickup section 53, and integrates a signal from the angular accelerometer 61. An integrator 62 that converts the angular velocity signal into an angular signal, an integrator 64 that integrates the angular velocity signal to obtain an angular signal, and an input of the angular velocity signal directly to the integrator 64, or the sign is inverted by a subtractor 63. An analog switch 66 for selecting whether to input to the integrator 64.
As in the third embodiment, the lens position control signal 20 from the control unit (not shown)
Are connected so as to be input as a reset signal.

Switching of the analog switch 66 is also performed when the control for setting the initial position of the projected image on the photographing screen from the normal state shown in FIG.
The sign inversion signal from 63 is input to the integrator 64 to switch the state.

The control operation of the image blur prevention apparatus having the above configuration will be described below with reference to FIG. 12. The output timings of the signals 20 and 21 are the same as those in the first embodiment.
The control can be performed by the same flowchart as described in the above. A timing signal for switching these control modes is output by a control IC of the electronic still camera.

The control operation shown in FIG.
This is similar to the control in the figure. That is, t <0 before the shutter release button (not shown) is pressed is the signal 20, 2
1 is “Hi”, and the rotational angular acceleration signal detected by the angular acceleration sensor 1 is converted into an angular velocity signal by the integrator 62, input to the integrator 64 through the analog switch 16, and converted into an angle signal. The angle signal from 64 is the rotation drive signal 56
As a result, the image blur prevention control is performed by the rotation of the imaging unit 53.

Next, when a shutter release button (not shown) is pressed (time t = 0), the signal 20 becomes "Lo" for a certain period of time as shown in FIG. Is reset, and its output becomes 0 (zero). Accordingly, the rotation drive unit 51c pulls the imaging unit 53 back to the center of the movable range in the rotation direction and stops the imaging unit 53.

After the elapse of the predetermined time, the signal 20 returns to “Hi”, and at the same time, the signal 21 becomes “Lo” for a short time Δt. Accordingly, the analog switch 66 is switched from the state shown in the figure, and the signal from the subtractor 63 is input to the integrator 64, whereby the signal output from the integrator 64 is used during the time Δt. The imaging unit 53 is moved in the forward direction with respect to the detected vibration in the rolling direction. When the time Δt has elapsed, the rotational movement of the imaging unit 53 in the same forward direction ends, and that position becomes the initial position of the imaging unit 53 at the start of the operation of the image blur prevention control.

After the elapse of the time Δt, the signal 21 returns to “Hi”, so that the whole system is in the image blur prevention control state. That is, in this state, the signal from the integrator 62 (that is, the vibration signal of the detected camera shake) is input to the integrator 64 through the analog switch 66,
At 64, a camera shake angle signal is input to the rotation driving circuit 51c through the rotation driving circuit 52c, and the camera is in a control state in which the imaging unit 53 is rotationally moved to prevent image blur, and the projected image on the imaging unit 53 is Apparently stopped. In this state, the shutter is opened, and this state is continued for the shutter open time t _open , so that blur-free shooting is performed.

Note that the voltage range in which the integrator 64 can integrate may be set so as to be equal to the driving range of the rotation driving unit that is the lens driving device.

According to such a configuration, it is possible to configure an image blur prevention apparatus that effectively uses strokes even with respect to blurring of an image around the photographing optical axis.

(Correspondence Relationship between Configuration of the Embodiment and Claims) The correction lens 13 in the embodiment corresponds to an image displacement unit in the claims, and steps # 12 to # 14 in the flowchart shown in FIG. 3 are set. The configuration in which the reverse signal of the signal from the integrator 2 is connected to the analog switch 16 corresponds to the changing means.

(Effects of the Invention) According to the invention of the present application, it is possible to perform an image displacement operation in a wide range by effectively using an operation area of an image displacement unit that displaces an image on an image plane. When applied to an anti-shake device such as a camera, a wide range in which anti-shake is possible can be secured.

[Brief description of the drawings]

1 to 5 are views for explaining the configuration of an image blur prevention apparatus according to a first embodiment of the present invention. FIG. 1 is an overall circuit diagram, and FIG. FIG. 3 schematically shows a configuration of a control CPU of a camera which outputs a switching signal, FIG. 3 is a flowchart showing an operation of the control CPU, and FIGS. 4 and 5 correspond to switching of an analog switch. FIG. 4 is a diagram schematically illustrating a relationship between an operation state of release switches SW1 and SW2, an output state of signals 20 and 21, and a movement position of a correction lens. 6 and 7 are views for explaining Embodiment 2 of the present invention. FIG. 6 is an overall circuit diagram of the image blur prevention device, and FIG.
The figure schematically shows the relationship between the output states of the signals 20 and 21 corresponding to the switching of the analog switch and the movement position of the correction lens. 8 and 9 are views for explaining Embodiment 3 of the present invention. FIG. 8 is an overall circuit diagram of the image blur prevention device, and FIG.
The figure schematically shows the relationship between the output states of the signals 20 and 21 corresponding to the switching of the analog switch and the movement position of the correction lens. 10 to 12 are views for explaining a fourth embodiment of the present invention. FIG. 11 is a view showing an outline of a device for preventing blurring due to vibration in the rotation direction, and FIG. 11 is an image. FIG. 12 is a schematic circuit diagram of the shake preventing apparatus, and FIG. 12 is a diagram schematically showing a relationship between output states of signals 20 and 21 corresponding to switching of an analog switch and a rotational movement position of an imaging unit. FIG. 13 is a diagram showing an example of a configuration outline of a conventional image blur prevention device, and FIG. 14 is a diagram schematically showing a configuration of a control CPU of a camera that outputs a signal for switching a selection switch of the conventional example. FIG. 15 is a flowchart showing the operation of the control CPU, and FIGS. 16 and 17 show the operation states of the release switches SW1 and SW2 corresponding to the switching of the analog switches provided by the conventional example, and the signals 20 and 21. FIG. 3 is a diagram schematically illustrating a relationship between an output state and a movement position of a correction lens. 1: angular acceleration sensor, 2: integrator 3, 6, 8: subtractor, 7: differentiator 9: potentiometer 10: coil, 11: magnet 12: spring, 13: correction lens 16, 18: analog switch 19: Lens drive device 20: Lens position control signal 21: Drive reverse rotation signal

Claims (1)

(57) [Claims] 1. An image moving apparatus for displacing an image on an image forming surface by moving an image displacing means, wherein said setting means sets said image displacing means to a movement start initial position; Changing means for changing the movement start initial position.