JP2000105396A - Device provided with image blur correcting function - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent an image from being deteriorated all the more because insufficient image blur correction control is performed by calculating a control signal outputted to a correction optical system driving means by interpolation arithmetic calculation by using the previous control signal when processing load in the case of performing control other than the control of the correction optical system driving means is heavy. SOLUTION: An MPU 1 reads output from both of pitch and yaw vibration gyroscopes 6 and 7 from an A/D conversion terminal alternately in the midst of the opening operation of a shutter, obtains a current value (duty of PWM) at which the desired rotating speed of a motor is given from the read value, and drives a correction lens 12 by setting the obtained value in a specified register. When the load of the processing other than the driving control (IS control) of the lens 12 is heavy for the MPU 1, which performs processing for closing the shutter at the time of driving the shutter and processing for starting strobe light emission, the control signal outputted to the correction lens driving devices 10 and 11 is interpolated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in an apparatus having an image blur correction function for correcting a blur occurring in a device such as a camera.

[0002]

2. Description of the Related Art In a camera having a conventional image blur correction function, noise is superimposed on the output of a correction lens position detection circuit due to electric noise due to shutter control performed during image blur correction control during exposure and strobe light emission. However, there is a disadvantage that the accuracy of shake correction is affected.

In view of this point, Japanese Patent Application Laid-Open No. HEI 9-26173 proposes that the above-mentioned drawbacks are improved by performing the image blur correction control by the open control without using the correction lens position information at the time of the shutter control and the strobe light emission. 9-80512.

[0004]

However, in the above conventional example, as described above, the image blur correction control is performed by the open control without using the correction lens position information during the shutter control and the flash emission. In addition, when the load of the MPU for performing various control of the camera becomes heavy, the control of the image blur correction becomes insufficient due to a calculation delay at the time of the shutter control or the strobe light emission control, and in some cases, the image deteriorates. was there.

(Object of the Invention) An object of the present invention is to provide an apparatus with an image blur correction function which can prevent the image from being deteriorated by performing insufficient image blur correction control. Is what you do.

[0006]

To achieve the above object, according to the present invention, there is provided a correction optical system driving means for controlling a position of a correction optical system for correcting image blur,
Control means for controlling the correction optical system driving means and other driving means, wherein the control means controls the correction optical system when a processing load other than the control of the correction optical system driving means is heavy. A control signal output to the system driving means is a device with an image blur correction function that is calculated by interpolation using a previous control signal.

In the above arrangement, if the device having the image blur correction function is compared to a camera, the control is performed when the shutter driving means is controlled to perform a shutter closing operation, or when the strobe means is controlled to emit strobe light. In this case, the calculation for calculating the control signal to be output to the correction optical system driving means is thinned out, and the control signal in this period is calculated by interpolation using the previous control signal.

According to another aspect of the present invention, there is provided a correction optical system driving means for driving a correction optical system in two different directions to correct image blur, and a correction optical system driving means. And control means for controlling other driving means, and the control means outputs a control signal for performing one-way drive control of the correction optical system driving means depending on a load condition to be processed. Is a device with an image blur correction function that is calculated by an interpolation operation using the control signal.

In the above arrangement, if the device having the image blur correction function is compared to a camera, the control is performed when the shutter driving means is controlled to perform a shutter closing operation, or when the strobe means is controlled to emit a strobe light. In this case, the calculation for one-way calculation of the control signal to be output to the correction optical system driving means is thinned out, and the control signal in this period is calculated by interpolation using the previous control signal. I have.

According to another aspect of the present invention, there is provided a correction optical system driving means for driving a correction optical system in two different directions to correct image blur, and a correction optical system. Control means for controlling the driving means and other driving means, and attitude signal output means for outputting an attitude signal of this device, the control means, depending on the load to be processed and the status of the output of the attitude signal output means Is a device with an image blur correction function that calculates a control signal for performing one-way drive control of the correction optical system driving means by interpolation using a previous control signal.

In the above arrangement, if the device having the image blur correction function is compared with a camera, the control is performed when the shutter driving means is controlled to perform a shutter closing operation or when the strobe means is controlled to emit a strobe light. When the posture of the device is the horizontal position, the control signal for performing the lateral drive control of the correction optical system driving means, when the posture of the device is the vertical position, Control signals for performing vertical drive control of the correction optical system drive unit are calculated by interpolation using the previous control signals.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on illustrated embodiments.

FIG. 1 is a block diagram showing a circuit configuration of a camera with an image blur correction function according to a first embodiment of the present invention.

In the figure, 1 is an MPU (micro processing unit), 2 is a memory, 3 is a strobe device, 4 is a shutter, 5 is a drive circuit for driving the shutter 4, and 6 is a shake in the pitch direction. A vibrating gyroscope, 7 detects a yaw direction vibration,
Reference numerals 8 and 9 denote amplification circuits for amplifying the outputs of the vibrating gyroscopes 6 and 7, and reference numeral 10 denotes a correction lens driving device which drives the correction lens 12 in the pitch direction to correct image blur caused by hand vibration in the pitch direction. Is a correction lens driving device that drives the correction lens 12 in the yaw direction in order to correct image shake caused by camera shake in the yaw direction and the like, and 13 is a posture sensor for detecting the posture of the camera.

In FIG. 1, outputs of the vibrating gyroscopes 6 and 7 are connected to an A / D conversion input terminal of the MPU 1 via amplification circuits 8 and 9.

In this embodiment, control is performed using the angular velocity of camera shake detected by the vibrating gyroscopes 6 and 7. That is, the camera shake is corrected by driving the correction lens 12 in a direction in which the camera shake is corrected at a speed corresponding to the angular velocity of the camera shake.

The operation at the time of correcting the image blur caused by the camera shake will be described with reference to the flowcharts shown in FIGS.

When the main sequence of the camera is started by turning on the main switch of the camera or the like, first, in step # 101, the MPU 1 reads various types of data from an EEPROM (not shown) in a series of operations of initial processing. The parameter is read and stored at a predetermined address in the memory 2. Then, the process proceeds to a step # 102, where a first stroke of a release button (not shown) is performed to switch SW1.
When it is determined that the photographer has started a series of operations of the image stabilization system by turning on the camera or the like (IS operation started, but shake correction has not been performed), Step # 1
The process proceeds to 03, where variables used in the processing are initialized.

In the next step # 104, the correction lens 12 is centered. Specifically, first, the correction lens 12 is moved to one end point by the correction lens driving devices 10 and 11. That is, the MPU 1 moves the correction lens 12 in a predetermined direction by the motors in the correction lens driving devices 10 and 11. Then, the position of the correction lens 12 is detected by a position detection sensor (not shown), and when the correction lens reaches a predetermined position, the driving of the motor is stopped. Actually, since the drive amount differs in the pitch direction and the yaw direction, the drive in the direction reaching the predetermined position is stopped. This predetermined value is one end point of the moving range of the correction lens 12. Thereafter, the correction lens 12 is driven at a predetermined speed for a predetermined time in a predetermined direction (a direction opposite to the direction of the one-sided shift), and centering is performed at substantially the center of the moving range of the correction lens.

In the next step # 105, the following processing is performed.

The MPU 1 reads the output of the vibrating gyroscope 6 for detecting the pitch direction vibration from the A / D conversion input terminal. The camera shake signal read via the amplifier 8 becomes the center value of the input range of the A / D conversion when the camera shake angular velocity is zero, and becomes larger than the center value when the camera shake angular velocity is positive. When is negative, the output is smaller than the center value. Therefore, the MPU 1 obtains a value (Vp) obtained by subtracting the center value (Vo) of the input range of the A / D conversion from the output value (Vin) read from the A / D conversion input terminal, and uses this value (Vp). The control of the correction lens 12 is performed.

Then, the MPU 1 obtains the driving speed of the correction lens 12 from the above Vp. In this embodiment, the correction lens 12 is driven using a motor whose rotation speed is proportional to the current flowing through the motor.

Next, the MPU 1 obtains a current value that gives a desired rotational speed of the motor from the value of Vp. Now, the current flowing to the motor is not given as an analog quantity,
M (pulse width modulation) is given as a digital quantity. This is because when controlling the current using the MPU 1 is advantageous in terms of cost. Therefore, a table for obtaining the duty of PWM from the value of Vp is prepared, and the MPU 1 obtains the address of the memory in which the value of the duty of PWM is stored from the value of Vp, and reads the value. Set the PWM duty. It is desirable that this table be set in the EEPROM.

When the PWM cycle and duty are obtained as described above, the MPU 1 sets these values in a predetermined register. Thus, the PWM drive signal is supplied to the correction lens drive device 10. The correction lens driving device 10 to which the drive signal has been supplied drives the correction lens 12 in the pitch direction (vertical direction) until the next drive signal is supplied. That is, until the next drive signal is given, the correction lens 1 is driven at a constant speed according to the drive signal just given.
2 is driven.

Next, the routine proceeds to step # 106, where the following processing is performed.

The MPU 1 reads the output of the vibration gyro 7 for detecting the yaw direction vibration from the A / D conversion input terminal via the amplifier 9. Here, the MPU 1 obtains a value (Vy) obtained by subtracting the center value (Vo) of the input range of the A / D conversion from the output value (Vin) read from the A / D conversion input terminal, and uses this value (Vy). The control of the correction lens 12 is performed.

Then, the MPU 1 obtains a driving speed of the correction lens 12, that is, a current value that gives a desired rotation speed of the motor, from the above Vy. Now, as described above, the current flowing to the motor is not given as an analog amount, but is given as a PWM (pulse width modulation) digital amount. Therefore, similarly to the pitch direction, a table for obtaining the PWM duty from the value of Vy is prepared, and the MPU 1 obtains the address of the memory in which the corresponding value of the duty of PWM is stored from the value of Vy. By reading the value, the duty of PWM is set. It is desirable that this table be set in the EEPROM.

Next, when the PWM cycle and duty are determined, the MPU 1 sets these values in a predetermined register. As a result, the PWM drive signal is supplied to the correction lens drive device 11. The correction lens driving device 11 to which the drive signal has been supplied drives the correction lens 12 in the pitch direction (vertical direction) until the next drive signal is supplied.
That is, until the next drive signal is supplied, the correction lens 12 is driven at a constant speed in accordance with the supplied drive signal.

When the driving of the correction lens 12 is started in this way, the process proceeds to step # 107, and an IS process for stabilizing the driving of the correction lens 12 is performed for a fixed time. That is, as described above, the outputs of both the pitch and yaw vibrating gyroscopes are alternately read from the A / D conversion terminal, and a current value (duty of PWM) that gives a desired rotation speed of the motor is obtained from the value, and the value is obtained. The correction lens 12 is driven by setting in a predetermined register.

Then, it is determined in step # 108 that a photographing request (a request for shutter drive or the like) is made by turning on the switch SW2 by the second stroke of the release button during the IS processing. Then, after a certain wait time has elapsed, processing such as the start of the shutter opening operation from step # 109 is performed. If it is determined that a request for photographing (a request for shutter drive or the like) has been made after the elapse of the wait time, the process immediately shifts to processing such as starting a shutter opening operation.

In the processing such as the start of the shutter opening operation, the MPU 1 first drives the focus adjusting lens for focusing in step # 109 to perform focusing. Then, the shutter driving and the like based on the result of the photometry already performed are started. In other words, the timer is started, and the processing related to the start of the shutter closing operation and the flash emission is performed by the interruption of the timer.

More specifically, the MPU 1 first activates two timers as a result of the photometry when it requires strobe light emission by the strobe device 3, and otherwise activates one timer. Actually, the shutter opening operation is started (step # 1).
10), when the timer is started (step # 111), the processing shifts to the IS processing (step # 112).

During the shutter opening operation, the MPU 1 alternately reads the outputs of the vibrating gyroscopes 6 and 7 for both the pitch and the yaw from the A / D conversion terminal as described above, and obtains a current for providing a desired rotational speed of the motor based on the value. The value (duty of PWM) is obtained, and the value is set in a predetermined register to operate the correction lens 12. This IS processing operation is continued until an interruption by the timer occurs.

When the two timers are started, first, a timer interrupt for strobe light emission occurs. When an interrupt is generated by this timer, MPU1 returns to FIG.
First, in step # 151,
A timer interrupt for interpolation is enabled, and FIG.
The interpolation processing of the control to be output in (c) is permitted. This is because the MPU 1 is given a considerable load for the pre-processing of the strobe light emission, as described later, which causes a delay in the IS (image blur correction) processing. May cause the image to deteriorate,
This is to prevent this.

Then, the process proceeds to a step # 152, where a pre-process for executing the flash emission is performed. That is, the MPU 1 checks whether the shutter is opened by a predetermined amount.
The predetermined amount is determined based on the guide number of the strobe device and the result of the distance measurement already performed. The opening amount of the shutter is detected by a position detection sensor (not shown). That is, the MPU 1 detects the opening position of the shutter by a position detection sensor (not shown). If the shutter is opened to a predetermined position, the MPU 1 ends this preprocessing, proceeds to step # 153, and performs strobe light emission. Of course, if it is not necessary to emit strobe light, this process is not performed, and the timer for that is not started.

The interpolation processing of the output control shown in FIG. 3C, which is permitted in step # 151, will be described.

Since the interruption is permitted in step # 151, an interruption occurs at regular intervals during the pre-processing of the strobe light emission, and the interpolation processing of the IS is performed at the interruption timing.

The MPU 1 does not perform A / D conversion during this time.
In steps # 171 and # 172 in FIG. 3C, a new timing is generated from the timing generated by the interruption and the two PWM duty values (corresponding to the current values that provide the desired rotation speed of the motor) immediately before the interpolation processing. Obtain a PWM duty value. That is, the interpolation period is PW
Assuming that the M duty value changes linearly, the two PWM duty values PWM (n−
1) From PWM (n-2), the PWM duty value at the i-th interrupt from the start of interpolation is calculated using the following equation.

PWM (n + m) = a × (n + m) + b where a = PWM (n−1) −PWM (n−2) b = (n−1) × PWM (n−2) − (n−2) XPWM (n-1) m = i-1 Here, the time when the interpolation is started (the time when the first interrupt giving the timing of the interpolation occurs) is t = n, and the PWM duty value at that time is PWM (n). , The PWM duty value at the i-th interrupt from the interpolation start
WM (n + m). Then, the obtained PWM duty value (the value of PWM (n + m)) is set in a predetermined register, and the correction lens is driven by giving a desired rotation speed to the motor.

The setting of the interrupt for giving the timing of the interpolation is performed in advance, and here, only the permission of the interrupt is performed. Then, when returning from the interrupt for emitting the strobe light, the interrupt for obtaining the timing for this interpolation is prohibited.

After returning from the strobe light emission interrupt, the IS process (step # 112) is performed again. That is, as described above, the outputs of both the pitch and yaw vibration detection sensors are alternately read from the A / D conversion terminal.
From the value, a current value (P
WM), and the correction lens 12 is driven by setting the value in a predetermined register.

Also, when a timer interrupt for starting the shutter closing operation occurs, the MPU 1 similarly shifts to a mode for interpolating the output control signal. That is, in this case, the process shifts to the routine of FIG. 3B, and the MPU 1 first permits a timer interrupt for interpolation in step # 161. This is because the MPU 1 is given a considerable load to the pre-processing of the start of the shutter closing operation as described later, which causes a delay in the IS processing, and as a result, the correction lens 12
There is a possibility that the image may be degraded by driving the image data, and this is to prevent this.

Next, the routine proceeds to step # 162, where the MPU 1 performs pre-processing for shutter closing drive. That is, it is checked whether the shutter is opened by a predetermined amount. This predetermined amount is determined based on the result of the photometry already performed. The opening amount of the shutter is detected by a position detection sensor (not shown). That is, the MPU 1 detects the opening position of the shutter by a position detection sensor (not shown), and if the shutter has been opened to the predetermined position, stops the shutter opening operation, proceeds to step # 163, and starts the shutter closing operation.

Since the interruption is permitted in step # 161, an interruption occurs.
Steps # 171 and # 172 of (c) are executed, and interpolation of the output control signal is performed.

In other words, the MPU 1 does not perform A / D conversion during this time, and uses the timing generated by the interruption and the two PWM duty values (corresponding to the current value that gives the desired rotational speed of the motor) immediately before the interpolation processing. , A new PWM duty value is obtained. That is, assuming that the PWM duty value changes linearly during the interpolation period, the two immediately preceding PWM duty values PWM (n
-1), the PWM duty value at the i-th interrupt from the start of interpolation is obtained from PWM (n-2) using the following equation.

PWM (n + m) = a × (n + m) + b where a = PWM (n−1) −PWM (n−2) b = (n−1) × PWM (n−2) − (n−2) XPWM (n-1) m = i-1 Here, the time when the interpolation is started (the time when the first interrupt giving the timing of the interpolation occurs) is t = n, and the PWM duty value at that time is PWM (n). , The PWM duty value at the i-th interrupt from the interpolation start
WM (n + m). Then, the obtained PWM duty value is set to a value of PWM (n + m) in a predetermined register, and the correction lens is driven by giving a desired rotation speed to the motor.

The setting of the interrupt for giving the timing of the interpolation is performed in advance, and here, only the permission of the interrupt is performed. Then, when returning from the interrupt for emitting the strobe light, the interrupt for obtaining the timing for this interpolation is prohibited.

After returning from the interrupt for starting the shutter closing operation, the IS processing (step # 11) is performed again.
Perform 2). That is, as described above, the outputs of the pitch and yaw vibration detection sensors are alternately read from the A / D conversion terminal, and a current value (duty of PWM) that gives a desired rotation speed of the motor is obtained from the read value. Is set in a predetermined register to drive the correction lens 12.

As described above, the IS process (improvement of the image by driving the correction lens) is continued until the shutter is completely closed. The fact that the shutter is completely closed can be known, for example, by providing a switch that turns on when the shutter is closed. If the MPU 1 determines in step # 113 that the shutter is completely closed, Correction lens 1
2 is stopped, and the process returns to step # 102.

According to the above-described first embodiment, the MPU 1 performs a process for closing the shutter when the shutter is driven and a process for starting strobe light emission, other than the drive control (IS control) of the correction lens 12 for the MPU 1. When the load of the processing is heavy, the control signals output to the correction lens driving devices 10 and 11 are interpolated, so that the image is deteriorated by performing insufficient image blur correction control. Can be prevented. Further, it is possible to eliminate a case where shutter control and strobe light emission are not properly performed.

(Second Embodiment) Second embodiment of the present invention
In the camera with an image blur correction function according to the embodiment, the position signal is obtained by integrating the camera shake angular velocity detected by the vibration gyro, and control is performed using the value. That is, the camera shake is corrected by driving the correction lens in a direction for correcting the camera shake by an amount corresponding to the camera shake amount. The integral of the output of the vibrating gyroscope is A / D
The conversion may be performed by an integration circuit provided outside the MPU before the conversion. However, in this embodiment, the A / D conversion
It is performed by a so-called digital filter performed by U.

The circuit configuration of a camera with an image blur correction function according to the second embodiment of the present invention is the same as that of FIG.

Hereinafter, the operation at the time of image blur correction due to camera shake will be described with reference to the flowcharts of FIGS.

When the main sequence of the camera is started by turning on the main switch of the camera or the like, first, in step # 201, the MPU 1 reads various types of data from an EEPROM (not shown) in a series of initial processing operations. The parameter is read and stored at a predetermined address in the memory 2. Then, the process proceeds to step # 202, where the first stroke of the release button (not shown) is performed, and the switch SW1
When it is determined that the photographer has started a series of operations of the image stabilization system by turning on the camera or the like (IS operation start, but shake correction has not been performed yet), step # 2 is performed.
The process proceeds to 03, where variables used in the processing are initialized. In the present embodiment, since a driving device using a moving magnet (MM) is employed, the correction lens 12 is positioned substantially at the center when current is not supplied to the coil by a spring attached to the moving magnet (MM). Therefore, the centering as in the first embodiment is unnecessary.

In the next step # 204, the MPU
1 starts a timer for obtaining sampling timing. This timer generates an interrupt at regular intervals. The interval is determined by the camera shake correction ability, but is usually about 500 μsec to 1 msec.

The MPU 1 alternately reads the outputs of the vibrating gyroscopes 6 and 7 for detecting the pitch direction and yaw direction vibrations from the A / D conversion input terminal each time an interrupt from the timer occurs. Performs the following processing.

The output of the vibrating gyroscope 6 for detecting vibration in the pitch direction is read from the A / D conversion input terminal via the amplifier 8. This camera shake signal becomes the center value of the input range of the A / D conversion when the camera shake angular velocity is zero, becomes larger than the center value when the camera shake angular velocity is positive, and becomes the center value when the camera shake angular velocity is negative. The output is smaller. Therefore, the MPU 1 obtains a value (Vp) obtained by subtracting the center value (Vo) of the input range of the A / D conversion from the output value (Vin) read from the A / D conversion input terminal, and obtains this value (Vp).
The control of the correction lens 12 is performed using a value obtained by integrating.

Next, the MPU 1 performs digital filtering using the above Vp. In this method, integration and high-pass filtering performed in the preceding stage are performed simultaneously. The high-pass filtering is performed in order to prevent the integrated value from overflowing due to integration of a slight offset component superimposed on the Vp. The design of the digital filter varies depending on the accuracy of the camera shake correction required from the target camera shake frequency band and camera performance, but this time both the high-pass filter and the integrator have a pole of 1 Hz, and both poles have Design the 0.2Hz one, and the pole is changed from the 1Hz one during control.
Switch to 0.2 Hz. This makes it possible to eliminate the phase error during control and to stabilize the filter output at an early stage. This switching of the frequency serving as a pole is called "time constant switching".

In practice, the MPU 1 sequentially obtains outputs according to the following equations.

[0060] _{Yp n = a1 × (Xp n} -2 -Xp n) + a2
× Ypn _-1 + a3 × Ypn _-2 The parameters a1, a2 and a3 in the above equation are changed when the time constant is switched. This switching is performed about one second after the start of integration. Xp _n input values in the pitch direction of the filter at the n-th sampling point n, i.e. above Vp
It is. Also, Xp _n, Yp _n is the output value of the pitch direction filter in the n-th sampling point n, Xp
_n-1 and Yp _n-1 are the input value and output value of the filter in the pitch direction at the (n-1) th sampling point n-1 and Xp
_n-2 and Ypn _-2 are input values and output values of the filter in the pitch direction at the (n-2) th sampling point.

In the first sampling (n = 0),
Xpn _-2 , Ypn _-1 and Ypn _-2 are set to zero. Similarly, in the second sampling (n = 1), Xpn _-2 , Y
_pn-2 is set to zero.

[0062] Then, MPU 1 obtains the driving position of the correction lens 12 from the Yp _n. In this embodiment, a driving device is used in which the correction lens 12 moves to a position proportional to a current flowing through a coil using a moving magnet (MM).

[0063] MPU1 obtains the current value applied from the value of Yp _n the coil. At present, the current flowing through the coil is not given as an analog amount, but is given as a PWM (pulse width modulation) digital amount. This is MP
Controlling the current using U1 is advantageous in terms of cost. Therefore, by preparing a table for determining the duty of PWM from the value of Yp _n, MPU 1
Obtains the address of the memory where the duty value of the PWM corresponding the value of Yp _n is stored, to set the duty of the PWM by reading that value. It is desirable that this table be set in the EEPROM.

When the PWM cycle and duty are obtained in this way, the MPU 1 sets these values in a predetermined register. Thus, the PWM drive signal is supplied to the correction lens drive device 10. The correction lens driving device 10 to which the drive signal has been supplied flows a current value proportional to the supplied signal to the coil, and drives the correction lens 12 to a predetermined position in the pitch direction (vertical direction). That is, until the next drive signal is given, the correction lens 12 is held at a predetermined position in accordance with the currently given drive signal.

When an interrupt from the next timer occurs, M
PU1 detects the shake in the yaw direction.
Proceeding to step 06, the following processing is performed.

The output of the vibrating gyroscope 7 is read from the A / D conversion input terminal via the amplifier 9. Here, MPU1 is A
From the output value (Vin) read from the / D conversion input terminal to A
A value obtained by subtracting the center value (Vo) of the input range of the / D conversion (V
y) is obtained, and the correction lens is controlled using this value (Vy).

Next, the MPU 1 performs digital filtering using the Vy. In this method, integration and high-pass filtering performed in the preceding stage are performed simultaneously. This time, both the high-pass filter and the integrator have a pole of 1 Hz.
Both poles are designed with 0.2 Hz, and the pole is switched from 1 Hz to 0.2 Hz during control. This switching of the frequency serving as a pole is referred to as "time constant switching" as described above.

In practice, the MPU 1 sequentially obtains outputs according to the following equation.

[0069] _{Yy n = a1 × (Xy n} -2 -Xy n) + a
2 × Yyn _-1 + a3 × Yyn _-2 The parameters a1, a2 and a3 in the above equation are changed when the time constant is switched. This switching is performed about one second after the start of integration. Xy _n input value of the yaw direction of the filter in the n-th sampling point n, that is, above Vy. Further, Yy _n is the output value of the yaw direction of the filter in the n-th sampling point n, Xy _n-1, Yy _n-1 is the input value of the yaw direction of the filter at n-1 th sampling point n-1, the output Values, Xyn _-2 and Yyn _-2 are n-
The input value and the output value of the filter in the yaw direction at the second sampling point.

In the first sampling (n = 0),
Xyn _-2 , Yyn _-1 and Yyn _-2 are assumed to be zero. Similarly, in the second sampling (n = 1), Xyn _-2 , Y
y _n-2 is set to zero.

[0071] Then, MPU 1 obtains the driving position of the correction lens 12 from Yy _n. In this embodiment, a driving device is used in which the correction lens 12 moves to a position proportional to a current flowing through a coil using a moving magnet (MM).

[0072] MPU1 obtains the current value applied to the coil from the value of Yy _n. At present, the current flowing through the coil is not given as an analog amount, but is given as a PWM (pulse width modulation) digital amount. Therefore, Yy
A table for obtaining the PWM duty from the value of _n is prepared, and the MPU ₁ determines the corresponding PWM from the value of Yyn.
The duty of the PWM is set by obtaining the address of the memory in which the duty value is stored and reading the value. It is desirable that this table be set in the EEPROM.

When the PWM cycle and duty are determined in this way, the MPU 1 sets these values in a predetermined register. As a result, the PWM drive signal is supplied to the correction lens drive device 11. The correction lens driving device 11 to which the drive signal has been supplied flows a current value proportional to the supplied signal to the coil, and drives the correction lens 12 to a predetermined position in the yaw direction (horizontal direction). That is, until the next drive signal is given, the correction lens 12 is held at a predetermined position in accordance with the currently given drive signal.

When the driving of the correction lens 12 is started in this way, the process proceeds to step # 207, and the IS process for stabilizing the driving of the correction lens 12 is performed for a fixed time. That is, every time an interruption from the timer occurs, the outputs of the pitch and yaw vibrating gyroscopes 6 and 7 are alternately read from the A / D conversion terminal, and digital filtering operation is performed. The correction lens 12 is driven by obtaining a current value (PWM duty) flowing through a coil for providing the 12 drive positions and setting the value in a predetermined register.

Then, it is determined in step # 208 that a request for photographing (a request for shutter driving or the like) is made by turning on the switch SW2 by the second stroke of the release button during the IS processing. Then, after a certain wait time has elapsed, processing such as the start of the shutter opening operation after step # 209 is performed. If it is determined that a request for photographing (a request for shutter drive or the like) has been made after the elapse of the wait time, the process immediately shifts to processing such as starting a shutter opening operation.

In the processing such as the start of the shutter opening operation, the MPU 1 first drives the focus adjusting lens for focusing in step # 209 to focus. Then, the shutter driving and the like based on the result of the photometry already performed are started. That is, the timer is started, and the processing related to the start of the shutter closing operation and the emission of the strobe light is performed by the interruption of the timer.

Specifically, the MPU 1 first determines the result of photometry,
Activate two timers when strobe firing is required, and one timer otherwise. Actually, when the shutter opening operation is started (step # 210) and the timer is started (step # 211), the processing is the IS processing (step # 210).
212).

During the shutter opening operation, the MPU 1 alternately reads the outputs of both the pitch and yaw vibrating gyroscopes 6 and 7 from the A / D conversion terminal each time the timer interrupt occurs as described above, and gives the output to the coil based on the value. The correction lens 12 is driven by obtaining a current value (PWM duty) and setting the value in a predetermined register. This IS processing operation is continued until an interruption by the timer occurs.

When the two timers are started, first, a timer interrupt for emitting a strobe light occurs. When the interruption by the timer occurs, the processing shifts to the routine of FIG. 5A, where steps # 251 and # 252 and FIG.
The following one-axis direction interpolation processing is performed by the steps # 271 and # 272 of (c).

The MPU 1 continues the digital filter operation for driving the correction lens 12 in only one axis direction, but temporarily stops the operation of the other digital filter.
1 performs interpolation of the control signal to be output, and
Drive.

Since the interruption for the interpolation process is permitted in step # 251, an interruption for the interpolation occurs at regular intervals during the pre-processing of the strobe light emission.

Each time this interrupt occurs, MPU 1
Without performing D conversion, a new PWM duty value is obtained from the timing caused by the interrupt and the two PWM duty values (corresponding to the current values that provide the driving position of the correction lens) immediately before the interpolation processing. That is,
Assuming that the PWM duty value changes linearly during the interpolation period, the two immediately preceding PWM duty values PW
From M (n-1) and PWM (n-2), the PWM duty value at the i-th interruption from the start of interpolation is obtained using the following equation.

PWM (n + m) = a × (n + m) + b where a = PWM (n−1) −PWM (n−2) b = (n−1) × PWM (n−2) − (n−2) XPWM (n-1) m = i-1 Here, the time when the interpolation is started (the time when the first interrupt giving the timing of the interpolation occurs) is t = n, and the PWM duty value at that time is PWM (n). , The PWM duty value at the i-th interrupt from the interpolation start
WM (n + m). Then, the obtained PWM duty value is set to a value of PWM (n + m) in a predetermined register, and a current is supplied to the coil so that the correction lens 1
2 is driven.

The setting of the interrupt for giving the timing of the interpolation is performed in advance, and here, only the permission of the interrupt is performed. Then, when returning from the interrupt for emitting the strobe light, the interrupt for obtaining the timing for this interpolation is prohibited.

Whether the digital filter operation in the pitch or yaw direction is temporarily stopped and the output interpolation is performed depends on the output of the attitude sensor 13. That is, the output of the attitude sensor 13 is read to determine the attitude of the camera. As a result, the digital filter operation in the yaw direction is temporarily stopped when the camera is in the horizontal position, and the digital filter operation in the pitch direction is temporarily stopped when the camera is in the vertical position. Output interpolation for This is because, in the horizontal position, the camera shake in the pitch direction is generally large, and in the vertical position, the camera shake in the yaw direction is large. Because it can be.

The one-axis digital filter operation is temporarily stopped and the output is interpolated. When the two-axis digital filter operation is performed and the correction lens 12 is driven, as described later, the MPU 1 Is subjected to a considerable load, which causes a delay in IS processing, and consequently, driving the correction lens 12 may degrade the image.

Thereafter, the flow advances to step # 253 to check whether or not the shutter is opened by a predetermined amount. The predetermined amount is determined based on the guide number of the strobe device 3 and the result of the distance measurement that has already been performed. The opening amount of the shutter is detected by a position detection sensor (not shown). That is, the MPU 1 detects the opening position of the shutter by a position detection sensor (not shown), and if the shutter has been opened to a predetermined position, the process proceeds to step # 254 to perform strobe light emission. Of course, if there is no need to emit strobe light, this process is not performed, and the timer for that is not started.

After returning from the interrupt for emitting the strobe light, the IS processing is again performed (step # 212).
To drive the correction lens 12 in both the pitch and yaw directions. That is, every time an interruption from the timer occurs, the outputs of both the pitch and yaw vibrating gyroscopes are alternately read from the A / D conversion terminal, digital filtering operation is performed, and a desired correction lens driving position is obtained from the result. Then, the correction lens 12 is driven by obtaining a current value (duty of PWM) flowing through the coil giving the value, and setting the value in a predetermined register.

When a timer interrupt for starting the shutter closing operation occurs, the process shifts to the routine of FIG. 5B in order to perform the same processing. Then, first in steps # 261 and # 262, the MPU 1
The axis (pitch or yaw direction) in which the interpolation processing is performed is determined based on the output of No. 3, and when an interruption occurs, the interpolation processing is performed and the correction lens 12 is driven.

Thereafter, the flow advances to step # 263 to perform pre-processing for closing the shutter. That is, the MPU 1 checks whether the shutter is opened by a predetermined amount. This predetermined amount is determined based on the result of the photometry already performed. The opening amount of the shutter is detected by a position detection sensor (not shown). That is, the MPU 1 detects the opening position of the shutter by a position detection sensor (not shown), stops the shutter opening operation if the shutter is opened to a predetermined position, and starts the shutter closing operation in the next step # 264. Also,
If it is a situation that the strobe device 3 should be turned on based on photometric value information or the like, before checking the opening amount of the shutter, it is checked whether the strobe device 3 is already turned on. To turn on the flash device 3.

After returning from this interrupt, I
The S process (step # 212) is performed to drive the correction lens 12 in both the pitch and yaw directions. That is, as described above, each time an interrupt from the timer occurs, the outputs of the pitch and yaw vibrating gyroscopes 6 and 7 are alternately read from the A / D conversion terminal and digital filtering is performed.
Based on the result, a current value (PWM duty) to be supplied to a coil for providing a desired correction lens driving position is obtained, and the correction lens 12 is driven by setting the value in a predetermined register.

As described above, the IS processing (improvement of the image by driving the correction lens) is continued until the shutter is completely closed. The fact that the shutter is completely closed can be known, for example, by providing a switch that is turned on when the shutter is closed. If it is determined in step # 213 in FIG. 4 that the shutter is completely closed, the correction is performed. The driving of the lens 12 is stopped, and the process returns to step # 202.

According to the above-described second embodiment, the MPU 1 performs a process for closing the shutter and a process for starting strobe light emission when the shutter is driven, except for the drive control (IS control) of the camera shake correction lens for the MPU 1. When the processing load is heavy, the correction lens drive control (IS control) is temporarily stopped in one direction, and the control signal during this time is calculated by interpolation. It is possible to prevent the image from being deteriorated by the control.

(Third Embodiment) FIG. 6 is a block diagram showing a circuit configuration of a camera with an image blur correction function according to a third embodiment of the present invention. And description thereof is omitted.

In FIG. 6, reference numeral 14 denotes a pause axis designation switch for designating an axis direction in which the driving of the correction lens 12 is temporarily suspended when the load of processing other than the IS processing of the MPU 1 is heavy.

In this embodiment, the position signal is obtained by integrating the angular velocity of camera shake detected by the vibrating gyroscope, and control is performed using the value. That is, the camera shake is corrected by driving the correction lens in a direction for correcting the camera shake by an amount corresponding to the camera shake amount. The integration of the vibration gyro output is performed by the MPU before A / D conversion.
Although it may be performed by an integrating circuit provided externally, in this embodiment, it is performed by a so-called digital filter performed by the MPU 1 after A / D conversion.

Also, in this embodiment, the MPU 1 is provided with a shutter drive pre-process and a strobe-on pre-process.
When the load of the processing other than the processing is heavy, the digital filter calculation in one axis direction (pitch or yaw direction) is temporarily stopped, and the interpolation of the control signal to be output is performed. In order to prevent the resulting image from being deteriorated, the axial direction for correcting the control signal output for driving the correction lens 12 is designated by a temporary stop axis designation switch 14 provided outside.

The operation at the time of image correction due to camera shake will be described with reference to the flowcharts of FIGS.

When the main sequence of the camera is started by turning on the main switch of the camera or the like, first, in step # 301, the MPU 1 reads various types of data from an EEPROM (not shown) in a series of operations of initial processing. The parameter is read and stored at a predetermined address in the memory 2. Then, the flow advances to step # 302, where the first stroke of the release button (not shown) is performed and the switch SW1 is turned on.
When it is determined that the photographer has started a series of operations of the image stabilization system by turning on the camera or the like (IS operation started, but shake correction has not been performed yet), Step # 3
The process proceeds to 03, where variables used in the processing are initialized.

In the next step # 304, the MPU
1 starts a timer for obtaining sampling timing. This timer generates an interrupt at regular intervals. The interval is determined by the camera shake correction ability, but is usually about 500 μsec to 1 msec.

The MPU 1 alternately reads the outputs of the vibrating gyroscopes 6 and 7 for detecting the pitch and yaw directions from the A / D conversion input terminal each time an interrupt from the timer occurs. Performs the following processing.

The output of the vibrating gyroscope 6 for detecting the pitch direction vibration is read from the A / D conversion input terminal via the amplifier 8. This camera shake signal becomes the center value of the input range of the A / D conversion when the camera shake angular velocity is zero, becomes larger than the center value when the camera shake angular velocity is positive, and becomes the center value when the camera shake angular velocity is negative. The output is smaller. Therefore, the MPU 1 obtains a value (Vp) obtained by subtracting the center value (Vo) of the input range of the A / D conversion from the output value (Vin) read from the A / D conversion input terminal, and obtains this value (Vp).
The control of the correction lens 12 is performed using a value obtained by integrating.

Next, the MPU 1 performs digital filtering using the above Vp. In this method, integration and high-pass filtering performed in the preceding stage are performed simultaneously. The high-pass filtering is performed in order to prevent the integrated value from overflowing due to integration of a slight offset component superimposed on the Vp. The design of the digital filter varies depending on the accuracy of the camera shake correction required from the target camera shake frequency band and camera performance, but this time both the high-pass filter and the integrator have a pole of 1 Hz, and both poles have Design the 0.2Hz one, and the pole is changed from the 1Hz one during control.
Switch to 0.2 Hz. This makes it possible to eliminate the phase error during control and to stabilize the filter output at an early stage. This switching of the frequency serving as a pole is called "time constant switching".

In practice, the MPU 1 sequentially obtains outputs according to the following equations.

[0105] _{Yp n = a1 × (Xp n} -2 -Xp n) + a2
× Ypn _-1 + a3 × Ypn _-2 The parameters a1, a2 and a3 in the above equation are changed when the time constant is switched. This switching is performed about one second after the start of integration. Xp _n input values in the pitch direction of the filter at the n-th sampling point n, i.e. above Vp
It is. Also, Xp _n, Yp _n is the output value of the pitch direction filter in the n-th sampling point n, Xp
_n-1 and Yp _n-1 are the input value and output value of the filter in the pitch direction at the (n-1) th sampling point n-1 and Xp
_n-2 and Ypn _-2 are input values and output values of the filter in the pitch direction at the (n-2) th sampling point.

In the first sampling (n = 0),
Xpn _-2 , Ypn _-1 and Ypn _-2 are set to zero. Similarly, in the second sampling (n = 1), Xpn _-2 , Y
_pn-2 is set to zero.

[0107] Then, MPU 1 obtains the driving position of the correction lens 12 from the Yp _n. In this embodiment, a driving device is used in which the correction lens 12 moves to a position proportional to a current flowing through a coil using a moving magnet (MM).

[0108] MPU1 obtains the current value applied from the value of Yp _n the coil. At present, the current flowing through the coil is not given as an analog amount, but is given as a PWM (pulse width modulation) digital amount. This is MP
Controlling the current using U1 is advantageous in terms of cost. Therefore, by preparing a table for determining the duty of PWM from the value of Yp _n, MPU 1
Obtains the address of the memory where the duty value of the PWM corresponding the value of Yp _n is stored, to set the duty of the PWM by reading that value. It is desirable that this table be set in the EEPROM.

When the PWM cycle and duty are determined in this way, the MPU 1 sets these values in a predetermined register. Thus, the PWM drive signal is supplied to the correction lens drive device 10. The correction lens driving device 10 to which the drive signal has been supplied flows a current value proportional to the supplied signal to the coil, and drives the correction lens 12 to a predetermined position in the pitch direction (vertical direction). That is, until the next drive signal is given, the correction lens 12 is held at a predetermined position in accordance with the currently given drive signal.

When an interrupt from the next timer occurs, M
PU1 detects the shake in the yaw direction.
Proceeding to step 06, the following processing is performed.

The output of the vibrating gyroscope 7 is read from the A / D conversion input terminal via the amplifier 9. Here, MPU1 is A
From the output value (Vin) read from the / D conversion input terminal to A
A value obtained by subtracting the center value (Vo) of the input range of the / D conversion (V
y) is obtained, and the correction lens is controlled using this value (Vy).

Next, the MPU 1 performs digital filtering using the Vy. In this method, integration and high-pass filtering performed in the preceding stage are performed simultaneously. This time, both the high-pass filter and the integrator have a pole of 1 Hz.
Both poles are designed with 0.2 Hz, and the pole is switched from 1 Hz to 0.2 Hz during control. This switching of the frequency serving as a pole is referred to as "time constant switching" as described above.

In practice, the MPU 1 sequentially obtains outputs according to the following equations.

[0114] _{Yy n = a1 × (Xy n} -2 -Xy n) + a
2 × Yyn _-1 + a3 × Yyn _-2 The parameters a1, a2 and a3 in the above equation are changed when the time constant is switched. This switching is performed about one second after the start of integration. Xy _n input value of the yaw direction of the filter in the n-th sampling point n, that is, above Vy. Further, Yy _n is the output value of the yaw direction of the filter in the n-th sampling point n, Xy _n-1, Yy _n-1 is the input value of the yaw direction of the filter at n-1 th sampling point n-1, the output Values, Xyn _-2 and Yyn _-2 are n-
The input value and the output value of the filter in the yaw direction at the second sampling point.

At the first sampling (n = 0),
Xyn _-2 , Yyn _-1 and Yyn _-2 are assumed to be zero. Similarly, in the second sampling (n = 1), Xyn _-2 , Y
y _n-2 is set to zero.

[0116] Then, MPU 1 obtains the driving position of the correction lens 12 from Yy _n. In this embodiment, a driving device is used in which the correction lens 12 moves to a position proportional to a current flowing through a coil using a moving magnet (MM).

[0117] MPU1 obtains the current value applied to the coil from the value of Yy _n. At present, the current flowing through the coil is not given as an analog quantity, but is given as a PWM (pulse width modulation) and a digital quantity. Therefore, by preparing a table for determining the duty from the value of the PWM Yy _n, MPU 1 obtains the address of the memory the value of the PWM duty corresponding the value of Yy _n is stored, by reading the value Set the PWM duty. This table is an EEPROM
It is desirable to set to.

When the PWM cycle and duty are determined in this way, the MPU 1 sets these values in a predetermined register. As a result, the PWM drive signal is supplied to the correction lens drive device 11. The correction lens driving device 11 to which the drive signal has been supplied flows a current value proportional to the supplied signal to the coil, and drives the correction lens 12 to a predetermined position in the yaw direction (horizontal direction). That is, until the next drive signal is given, the correction lens 12 is held at a predetermined position in accordance with the currently given drive signal.

When the driving of the correction lens 12 is started in this way, the process proceeds to step # 307, and the IS process for stabilizing the driving of the correction lens 12 is performed for a fixed time. That is, every time an interruption from the timer occurs, the outputs of the pitch and yaw vibrating gyroscopes 6 and 7 are alternately read from the A / D conversion terminal, and digital filtering operation is performed. The correction lens 12 is driven by obtaining a current value (PWM duty) flowing through a coil for providing the 12 drive positions and setting the value in a predetermined register.

Then, it is determined in step # 308 that a photographing request (a request for shutter drive or the like) is made by turning on the switch SW2 by the second stroke of the release button during the IS process. Then, after a certain wait time has elapsed, processing such as the start of the shutter opening operation after step # 309 is performed. If it is determined that a request for photographing (a request for shutter drive or the like) has been made after the elapse of the wait time, the process immediately shifts to processing such as starting a shutter opening operation.

In the processing such as the start of the shutter opening operation, the MPU 1 first drives the focus adjusting lens for focusing in step # 309 to focus. Then, the shutter driving and the like based on the result of the photometry already performed are started. That is, the timer is started, and the processing related to the start of the shutter closing operation and the emission of the strobe light is performed by the interruption of the timer.

Specifically, the MPU 1 first determines the result of photometry,
Activate two timers when strobe firing is required, and one timer otherwise. Actually, when the shutter opening operation (step # 310) is started and the timer is started (step # 311), the processing is the IS processing (step # 310).
312).

During the shutter opening operation, the MPU 1 alternately reads the outputs of both the pitch and yaw vibrating gyroscopes 6 and 7 from the A / D conversion terminal every time the timer interrupt occurs as described above, and gives the output to the coil based on the value. The correction lens 12 is driven by obtaining a current value (PWM duty) and setting the value in a predetermined register. This IS processing operation is continued until an interruption by the timer occurs.

When the two timers are activated, first, a timer interrupt for emitting a strobe light occurs. When the interruption by the timer occurs, the process proceeds to the routine of FIG.
In steps # 371 and # 372 of (c), the following uniaxial interpolation processing is performed.

The MPU 1 temporarily stops driving the correction lens 12 only in one axis direction. Whether the correction lens driving in the pitch or yaw direction is temporarily stopped is designated by the pause axis designation switch 14.

Since the interruption for the interpolation is permitted in step # 351, the interruption for the interpolation occurs every predetermined period during the pre-processing of the strobe light emission. Each time this interrupt occurs, the MPU 1 does not perform A / D conversion, and obtains a new timing based on the timing generated by the interrupt and the three PWM duty values (corresponding to the current values for providing the driving position of the correction lens) immediately before the interpolation processing. A suitable PWM duty value. That is, assuming that the PWM duty value changes quadratically during the interpolation period, the three immediately preceding PWM duty values PWM (n-1) and PWM (n-1) are used.
From (n-2) and PWM (n-3), a PWM duty value at the i-th interruption from the start of interpolation is obtained using the following equation.

PWM (n + m) = a × (n + m) ² + b × (n + m) + c where a = PWM (n−3) −2 × PWM (n−2) + PWM (n−1) b = PWM (n−) 2) -PWM (n-3) -a * (2n-5) c = PWM (n-3) -a * (n-3) ² -b * (n-3) m = i-1 Interpolation here Is started (the time when the first interrupt giving the timing of interpolation occurs) is t = n, the PWM duty value at that time is PWM (n), and the PWM duty value at the i-th interrupt from the interpolation start is P
WM (n + m). Then, the obtained PWM duty value is set to a value of PWM (n + m) in a predetermined register, and a current is supplied to the coil to drive the correction lens.

The setting of the interrupt for giving the timing of the interpolation is performed in advance, and here, only the permission of the interrupt is performed. Then, when returning from the interrupt for emitting the strobe light, the interrupt for obtaining the timing for this interpolation is prohibited.

The reason why the one-axis digital filter operation is temporarily stopped and the output signal is interpolated is that when the two-axis digital filter operation is performed and the correction lens is driven, the MPU performs a pre-process of strobe light emission as described later. This is because a considerable load is applied, which causes a delay in IS processing, and consequently driving the correction lens with the calculated signal may deteriorate the image.

Thereafter, the flow advances to step # 353 to carry out pre-processing of strobe light. That is, the MPU 1 checks whether the shutter is opened by a predetermined amount. The predetermined amount is determined based on the guide number of the strobe device 3 and the result of the distance measurement that has already been performed. The opening amount of the shutter is detected by a position detection sensor (not shown). That is,
The MPU 1 detects the opening position of the shutter by a position detection sensor (not shown), and if the shutter has been opened to a predetermined position, the process proceeds to step # 354 to perform strobe light emission. Of course, if there is no need to emit strobe light, this process is not performed, and the timer for that is not started.

After returning from the timer interrupt for emitting the strobe light, the IS processing is again performed (step # 3).
12) to drive the correction lens 12 in both the pitch and yaw directions. That is, every time an interruption from the timer occurs, the outputs of both the pitch and yaw vibrating gyroscopes are alternately read from the A / D conversion terminal, digital filtering operation is performed, and a desired correction lens driving position is obtained from the result. Then, the correction lens 12 is driven by obtaining a current value (duty of PWM) flowing through the coil giving the value, and setting the value in a predetermined register.

When a timer interrupt for starting the shutter closing operation occurs, the same processing is performed, so that the routine shifts to the routine of FIG. 8B, and steps # 361 and # 3 are performed.
At 62, the MPU 1 reads the setting of the pause axis switch 14, and performs an interpolation process in the designated direction (pitch or yaw direction). The above-described interpolation processing of steps # 371 and # 372 in FIG. 8C is performed when an interrupt occurs.

That is, the MPU 1 does not perform A / D conversion during this period, and determines the timing generated by the interruption and the three PWM duty values (corresponding to the current values for providing the driving position of the correction lens) immediately before the start of the interpolation processing. Obtain a new PWM duty value. That is, assuming that the PWM duty value changes in a quadratic function during the interpolation period, the three immediately preceding PWM duty values PWM
From (n-1), PWM (n-2), and PWM (n-3), the PWM duty value at the i-th interrupt from the start of interpolation is obtained using the following equation.

PWM (n + m) = a × (n + m) ² + b × (n + m) + c where a = PWM (n−3) −2 × PWM (n−2) + PWM (n−1) b = PWM (n− 2) -PWM (n-3) -a * (2n-5) c = PWM (n-3) -a * (n-3) ² -b * (n-3) m = i-1 Interpolation here Is started (the time when the first interrupt giving the timing of interpolation occurs) is t = n, the PWM duty value at that time is PWM (n), and the PWM duty value at the i-th interrupt from the interpolation start is P
WM (n + m). Then, the obtained PWM duty value is set to a value of PWM (n + m) in a predetermined register, and a current is supplied to the coil to give a desired rotation speed to the motor, thereby driving the correction lens.

The setting of an interrupt for giving the timing of the interpolation is performed in advance, and here, only the permission of the interrupt is performed. Then, when returning from the interrupt for the shutter closing process, the interrupt for obtaining the timing for the interpolation is prohibited.

As described above, when the digital filter operation in one axis direction is temporarily stopped and the interpolation of the output signal is performed, the digital filter operation of the two axes is performed and the correction lens is driven. The MPU is subject to a considerable load for the pre-processing, which causes a delay in the processing of the IS, and consequently driving the correction lens with the calculated signal may conversely degrade the image. is there.

Thereafter, the flow advances to step # 363 to perform pre-processing for closing the shutter. That is, the MPU 1 checks whether the shutter is opened by a predetermined amount. This predetermined amount is determined based on the result of the photometry already performed. The opening amount of the shutter is detected by a position detection sensor (not shown). That is, the MPU 1 detects the opening position of the shutter by a position detection sensor (not shown), stops the shutter opening operation if the shutter is opened to the predetermined position, and starts the shutter closing operation in the next step # 364. Also,
If it is a situation that the strobe device 3 should be turned on based on photometric value information or the like, before checking the opening amount of the shutter, it is checked whether the strobe device 3 is already turned on. To turn on the flash device 3.

After returning from the timer interrupt for starting the shutter closing operation, the IS processing is again performed (step #).
312) to perform the correction lens 12 in both the pitch and yaw directions.
Is driven. That is, every time an interruption from the timer occurs, as described above, the outputs of the vibrating gyroscopes 6 and 7 for both pitch and yaw are alternately read from the A / D conversion terminal, digital filtering operation is performed, and a desired correction lens is obtained from the result. Then, the correction lens 12 is driven by obtaining the current value (PWM duty) flowing through the coil that gives the drive position of the above, and setting the value in a predetermined register.

As described above, the IS processing (improvement of the image by driving the correction lens) is continued until the shutter is completely closed. The fact that the shutter is completely closed can be known, for example, by providing a switch that is turned on when the shutter is closed. If it is determined in step # 313 of FIG. 4 that the shutter is completely closed, correction is performed. The driving of the lens 12 is stopped, and the process returns to step # 302.

According to the third embodiment described above, the processing for closing the shutter and the processing for starting the strobe light emission when the shutter is driven are performed. For the MPU 1, the processing other than the drive control (IS control) of the correction lens is performed. When the processing load is heavy, the axis for performing the interpolation processing of the drive control (IS control) of the correction lens is designated from the outside, and the control signal during this time is calculated by interpolation. It is possible to prevent the image from being deteriorated by the control of the image blur correction.

(Correspondence between the Invention and the Embodiment) In each of the above embodiments, the correction lens driving devices 10 and 11 are used as the correction optical system driving means of the present invention, the MPU 1 is used as the control means of the present invention, and the posture detecting sensor 13 is used. And pause axis designation switch 14
Correspond to the attitude signal output means of the present invention.

The correspondence between the components of the embodiment and the components of the present invention has been described above. However, the present invention is not limited to the configuration of the embodiment, and the functions and functions described in the claims are not limited.
Needless to say, any configuration may be used as long as the functions of the embodiment can be achieved.

(Modification) In each of the above embodiments,
As an example in which the processing load other than the correction lens drive control (IS control) is heavy, the shutter close drive and the strobe light emission start are taken as examples. However, the present invention is not limited to this.
Any type of U may be used as long as the processing load is increased by performing the process simultaneously with the drive control of the correction lens.

Further, an example is shown in which a shift type correction lens is used as the correction optical system, but a variable apex angle prism may be used.

The present invention has been described with respect to an example in which the present invention is applied to a camera. However, other than the camera, optical devices and other devices provided with an image blur correction function, and devices applied to those optical devices and other devices, Alternatively, the present invention can also be applied to elements constituting these.

[0146]

As described above, according to the present invention,
An object of the present invention is to provide a device with an image blur correction function that can prevent the image from being degraded by performing insufficient image blur correction control.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a circuit configuration of a camera with an image blur correction function according to first and second embodiments of the present invention.

FIG. 2 is a flowchart showing an operation of a part of the camera with an image blur correction function according to the first embodiment of the present invention.

FIG. 3 is a flowchart illustrating another operation of the camera with an image blur correction function according to the first embodiment of the present invention.

FIG. 4 is a flowchart showing an operation of a part of a camera with an image blur correction function according to a second embodiment of the present invention.

FIG. 5 is a flowchart illustrating another operation of the camera with the image blur correction function according to the second embodiment of the present invention.

FIG. 6 is a block diagram illustrating a circuit configuration of a camera with an image blur correction function according to a third embodiment of the present invention.

FIG. 7 is a flowchart showing an operation of a part of a camera with an image blur correction function according to a third embodiment of the present invention.

FIG. 8 is a flowchart illustrating another operation of the camera with the image blur correction function according to the third embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 MPU 2 Memory 3 Strobe device 4 Shutter 5 Drive circuit, 6,7 Vibration gyroscope 10,11 Correction lens drive device 12 Correction lens 13 Attitude sensor 14 Temporary stop axis designation switch

Claims (6)

[Claims] A correction optical system driving means for controlling a position of the correction optical system for correcting image blur; and a control means for controlling the correction optical system driving means and other driving means. The means calculates a control signal to be output to the correction optical system driving means by interpolation using a previous control signal when a processing load when performing control other than the control of the correction optical system driving means is heavy. A device with an image blur correction function, characterized in that: 2. A control signal output to the correction optical system driving means when the shutter driving means controls the shutter driving means to perform a shutter closing operation. 2. The apparatus with an image blur correction function according to claim 1, wherein the calculation is performed by interpolation using a previous control signal. 3. The electronic apparatus according to claim 1, further comprising a strobe means, wherein said control means includes:
When performing control for causing the strobe means to emit strobe light during the shutter drive, calculating a control signal to be output to the correction optical system drive means by interpolation using a previous control signal. Claim 1.
Or an apparatus with an image blur correction function according to 2. 4. A correction optical system driving unit for driving the correction optical system in two different directions to correct image blur, and a control unit for controlling the correction optical system driving unit and other driving units, The control unit controls the unidirectional drive control of the correction optical system driving unit by a control signal, depending on the state of the load to be processed.
An apparatus with an image blur correction function, which is calculated by interpolation using a previous control signal. 5. A correcting optical system driving means for driving the correcting optical system in two different directions to correct image blur, a controlling means for controlling the correcting optical system driving means and other driving means, and an attitude of the apparatus. And a posture signal output unit for outputting a signal.The control unit is configured to perform one-way drive control of the correction optical system driving unit depending on a load to be processed and an output state of the posture signal output unit. An apparatus with an image blur correction function, wherein a control signal is calculated by interpolation using a previous control signal. 6. When the control unit determines that the posture of the apparatus is a horizontal position based on an output of the posture detection unit due to a heavy processing load when performing control other than control of the correction optical system driving unit. When a control signal for performing horizontal drive control of the correction optical system driving unit is determined to be a vertical position of the apparatus, the vertical drive control of the correction optical system driving unit is performed. 6. The apparatus with an image blur correction function according to claim 5, wherein the control signals to be performed are calculated by interpolation using the previous control signals.