JPH08307762A - Shake correcting device - Google Patents

Abstract

PURPOSE: To smoothly perform the switch between the operation and non- operation in an image correction means and to prevent the unnaturual feeling from being given to a user when a shake correction operation is performed. CONSTITUTION: This device is provided with a selection means 26 selecting the operating states of image correction means 9 and 9' and an image correction amount changing means 12 switching the operation/non-operation of the image correction means 9 and 9' in response to the selection state of the selection means 26 and varying the correction amount of the image correction means for the signal that a vibration detection means outputs with a prescribed time spent when the switchover is performed. When the operation/non-operation of the image correction means is switched, image correction amount is changed by the image correction amount changing means 12 with a prescribed time spent.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a shake correction device mounted on an optical device such as a photographing device.

[0002]

2. Description of the Related Art Conventionally, in the field of photographing devices such as cameras, automation and multifunctionality have been achieved in all respects such as exposure setting and focus adjustment so that good photographing can always be performed regardless of the photographing environment. It is like this.

However, it is often the camera shake that actually deteriorates the quality of a photographed image.
In recent years, various shake correction devices for correcting this camera shake have been proposed and are attracting attention.

The shake correction apparatus uses a correction system for optical correction and electrical correction by image processing, and a detection system for physical vibration detection and detection by image processing using a motion vector of an image. , Each is roughly divided. And many forms are considered by these combinations.

FIG. 12 shows a circuit configuration of a conventional shake correction apparatus.

In FIG. 1, reference numeral 1 denotes an angular velocity detecting means such as a vibration gyro which is an angular velocity sensor, and is attached to a photographing device or the like. 2 is the angular velocity detecting means 1
A DC cut filter that cuts off the DC component of the angular velocity signal output from the device, or a high-pass filter (HPF) that cuts off the signal in an arbitrary band, and 3 are amplifiers that amplify the angular velocity signal to an appropriate sensitivity. Reference numeral 4 is an A / D converter, and 5 is an HP having a function of changing characteristics in an arbitrary band.
F and 6 are integrating means, 7 is a phase and gain correcting means, 8 is a driving circuit, and 9 is an image correcting means. Reference numeral 10 is a pan / tilt and photographing state determination means using the angular velocity signal after A / D conversion and the angular displacement signal output from the integration means 6, and changes the frequency characteristic of the integration means 6 based on the determination result. .
The integrating means here is assumed to have cutoff characteristics in the low frequency range. Reference numeral 11 is a frequency and amplitude detecting means to which the angular velocity signal (output of the A / D converter 4) and the angular displacement signal (output of the integrating means 6) are input, and the phase and gain correcting means is determined by the detected frequency and detected amplitude. Correction is made at 7.

The above is the shake correction system for YAW (horizontal direction), and the shake correction system for PITCH (vertical direction) has the same configuration (1'-11 '). Since the same operation is performed in both cases, only the YAW side will be described below.

The A / D converter 4 to the phase / gain correction means 7, the pan / tilt and photographing state determination means 10, and the frequency / amplitude detection means 11 are implemented by, for example, a microcomputer (hereinafter also referred to as a microcomputer). It is realized, the angular velocity signal is converted into a digital value by the A / D converter 4, and the low frequency region removal calculation is performed by the HPF 5,
It is converted into an angular displacement signal in the integrating means 6.

Then, the control (panning control, frequency adaptive control, etc.) according to the shake applied to the photographing apparatus is taken into consideration in the phase and gain correction means 7, and D / not shown
Converted to an analog signal by the A converter, or
It is output from the microcomputer as a pulse output such as PWM.

Then, based on this angular displacement signal, the drive circuit 8 drives the image correction means 9 to suppress the shake.

Here, as the image correction means 9, for example, an optical correction means for displacing the optical optical axis to cancel the shake, or a memory storing the image electrically shifts the read position of the image. Image processing correction means for canceling the shake is used.

In order to realize the characteristics of the HPF 5, the integrator 6, and the phase and gain corrector 7 by a microcomputer or the like, a digital filter may be used. For such a digital filter, for example, a primary IIR filter is used. If so, u0 = a0.w0 + a1.w1 w0 = e0 + a2.w1 w1 = w0 (w1 is a state variable) e0: input u0: output a0, a1, b1: can be realized by calculation of filter coefficients, and filter coefficients a0, a1, a2
Since the frequency characteristic can be set by changing, the data of the corresponding filter coefficients a0, a1, and a2 are prepared as a table, and the IIR filter operation may be performed with the filter coefficient obtained by searching the table. .

Since the HPF 5, the integrating means 6, the phase and gain correcting means 7 are realized by using a digital filter or the like here, the sampling time must be relatively high (for example, about 1 kHz), but the pan / Tilt and shooting state determination means 10, frequency and amplitude detection means 11
May be a relatively slow cycle process.

Next, the processing operation on the microcomputer in this conventional example will be described with reference to the flowcharts of FIGS. 13 (a) and 13 (b).

First, FIG. 13 (a) is a flow chart concerning a deflection angle displacement signal calculation for controlling the drive of the image correcting means 9 such as a variable apex angle prism (VAP). [Step 201] The angular velocity signal from the angular velocity detecting means 1 is taken into the inside by the A / D converter 4 via the HPF 2 and the amplifier 3. [Step 202] The angular velocity signal captured in step 201 is stored in the RAM. [Step 203] The HPF calculation coefficient is read. [Step 204] The input angular velocity signal of step 201 is multiplied by the HPF calculation coefficient.

The storage of the angular velocity signal in step 202 may be performed by HPF calculation. In this case, the offset is removed in advance, which is convenient for detecting the shooting state such as panning detection, vibration frequency detection, and amplitude detection. [Step 205] The integration calculation coefficient is read. [Step 206] The angular velocity signal subjected to the HPF calculation in the above step 204 is converted into an angular displacement signal by calculation using the integration coefficient. [Step 207] The angular displacement signal obtained in the above step 207 is stored. [Step 208] The phase and gain correction coefficients are read. [Step 209] The angular displacement signal obtained in step 207 is subjected to correction calculation according to the judgment of the vibration frequency / amplitude and the photographing state. [Step 210] The control signal obtained in step 209 is converted into an analog value by a D / A converter (not shown in FIG. 12) or is output from the microcomputer as a pulse output such as PWM. [Step 211] A series of operations ends.

Next, FIG. 13B is a flow chart of processing relating to vibration frequency / amplitude detection, pan / tilt and photographing state detection, setting of respective calculation coefficients and the like. [Step 213] The angular velocity signal stored in step 202 is read. [Step 214] The angular velocity signal stored in step 207 is read. Note that the order of step 213 and step 214 does not matter. [Step 215] The shake center frequency and amplitude applied to the device are detected by inputting the angular velocity signal and the angular displacement signal of the above steps 213 and 214.

The shake amplitude is VA driven by a servo mechanism.
This is effective for correction processing when the servo characteristic is deteriorated (reduction of the follow-up amplitude) by a small amplitude in the image correction means such as P (for example, gain is set and changed according to the shake amplitude). [Step 216] The pan / tilt and the photographing state are determined by inputting the angular velocity signal and the angular displacement signal of the steps 213 and 214, and the shake center frequency and the amplitude detected in the step 215. [Step 217] The HPF calculation coefficient and the integral calculation coefficient of the HPF calculation coefficient are set based on the determination result of the pan / tilt and the photographing state. Further, the frequency correction coefficient is set based on the shake center frequency and amplitude obtained in step 215. [Step 218] A series of operations ends.

The coefficients according to the pan / tilt and the photographing state are searched from a data table obtained empirically. On the other hand, the frequency correction coefficient is searched from the data table preset for each frequency.

[0020]

However, in the shake correction device as described above, the following problems are solved:
Alternatively, there are issues to be improved. The details will be described later.

1) Instability of the system at power-on of the shake correction device and discontinuous operation at the time of switching between shake correction operation and non-operation.

2) False detection may occur due to noise.

3) When a low-resolution A / D converter, which is relatively inexpensive, is used, it is difficult to secure both the dynamic range and the high resolution for the input angular velocity signal.

4) If phase advance correction is performed inside the microcomputer, noise in the high frequency range will be amplified.

5) The gain in the unnecessary frequency range is large, which causes the generation of driving noise.

(Object of the Invention) A first object of the present invention is to provide a shake correction apparatus that smoothly switches between operation and non-operation of the image correction means and does not give a feeling of strangeness to the user during the shake correction operation. Is to provide.

A second object of the present invention is to reduce the noise level to the means for detecting the operating state of the optical equipment in which the apparatus is mounted, and to suppress erroneous detection even if the detection capability here is increased. An object of the present invention is to provide a shake correction device capable of performing the same.

A third object of the present invention is to provide a shake that can secure both a dynamic range and a high resolution for an input angular velocity signal, even if a relatively inexpensive A / D converter having a low resolution is used. A correction device is provided.

A fourth object of the present invention is to provide a shake correction device capable of suppressing noise in a high frequency range.

A fifth object of the present invention is to provide a shake correction device capable of suppressing the generation of drive noise of the optical correction means in the shake correction operation.

[0031]

In order to achieve the first object, the present invention according to claims 1 and 2 is a selection means for selecting an operation state of the image correction means, and a selection state of the selection means. In response to the change, the operation / non-operation of the image correction unit is switched, and at the time of the switching, an image correction amount changing unit for changing the correction amount of the image correction unit with respect to the signal output from the vibration detection unit is taken over a predetermined time. When the image correction means is switched between operating and non-operating, the image correction amount changing means changes the image correction amount over a predetermined time.

In order to achieve the second object, the present invention according to claim 3 is the first means for generating a drive signal for the image correcting means from the output from the angular velocity detecting means, and the angular velocity detecting means. A control means comprising: output means for detecting an operating state of an optical device in which the device is mounted; and second means for correcting the drive signal generated by the first means. A low-pass filter is arranged between the second means and a low-pass filter is provided only between the angular velocity detecting means and the second means, which is relatively susceptible to noise. I have to.

In order to achieve the third object, the present invention according to claim 4 appropriately monitors the output of the second amplifying means which is output to the digital calculating means, while appropriately adjusting the angular velocity signal from the angular velocity detecting means. A gain control means for controlling the gains of the first amplification means and the second amplification means for amplifying to various sensitivities,
While monitoring the output of the second amplifying means, the first and second
The gain of the amplifying means is controlled.

In order to achieve the above-mentioned fourth object, the present invention according to claim 5 provides phase advancing means before the A / D converting means or after the D / A converting means. A low-pass filter is provided after the A / D conversion means or before the D / A conversion means, and the phase is sufficiently advanced at the input side of the circuit portion configured by the microcomputer, and the microcomputer The phase correction is performed by changing the cutoff frequency of the low pass filter (LPF) arranged in the inside, and the quantum error is suppressed.

In order to achieve the above fifth object, the present invention according to claim 6 is characterized in that when the drive signal is a discrete signal or a smoothed signal thereof and the optical correction means is controlled by the signal, the signal is controlled. A control means for setting the output cycle of the above is set to a frequency with a low gain so as to prevent the gain in the unnecessary frequency band from increasing.

[0036]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below based on the illustrated embodiments.

FIG. 1 is a block diagram showing the structure of a shake correction apparatus according to the first embodiment of the present invention. The same parts as those in FIG. 12 are designated by the same reference numerals, and their details will be omitted.

Reference numeral 26 is an IS switch for selecting the operation or non-operation of the shake correction (IS) function. When the IS switch is turned from OFF to ON or when the power is turned on, the HPF is turned on.
2 (or HPF 5) and the characteristics of the integrating means 6 (cutoff frequency etc.) are variably controlled. Reference numeral 12 is an initial control device for realizing this, and the IS switch 2
When the IS operation is started by 6 or when the power is turned on, the control characteristics of the HPF 2 and the integrating means 6 are variably controlled, or the image correction amount is changed by the amplifier 13 to reduce the uncomfortable feeling when the IS operation / non-operation is switched. To do.

The image correction amount at this time is changed from 0% to 100% over a predetermined time when the IS operation is started or when the electric power is turned on. Also, the relationship between the time and the correction amount is set according to the characteristics of the angular velocity detecting means 1, and the storing means 2 is also set.
It is also possible to individually make arbitrary settings and change the correction function by using 7.

As described above, since the HPF 5, the integrating means 6, the phase and gain correcting means 7 are realized by using a digital filter or the like here, the sampling time must be relatively high (for example, about 1 kHz). ,Bread/
The tilt / imaging state determination means 10 and the frequency / amplitude detection means 11 may be processed in a relatively slow cycle. In other words, these can be changed according to the situation.

Here, as an example of the image correction means, a variable apex prism (vari angle prism, hereinafter referred to as VAP).
And a voice coil is used as a drive system, and a configuration of closed loop control by an angular displacement encoder is given.

In FIG. 2, the VAP 306 is a holding frame 3
It is fixed to the lens barrel 302 so as to be rotatable about the axes 301 and 311 via 07. 313 is a yoke, 3
15 is a magnet, 312 is a coil, and the coil 31
By passing an electric current through 2, the VA centering around the shaft 311
It is a voice coil type actuator that can change the P apex angle. Reference numeral 310 is a slit, and the rotating shaft 311
Works the same as. 308 is a light emitting diode, 309 is PS
D (Position Sennsinng Detector), which together with the slit 310 constitutes an encoder for detecting the angular displacement of the VAP apex angle.

Then, the light beam whose incident angle is changed by the VAP 306 is transferred to the CCD 304 by the lens 303.
Form an image on the surface. In addition, 305 has shown the other central axis.

A basic control example using these is shown in a block diagram in FIG.

322 is an amplifier, 323 is a driver, 32
4 is an actuator, 306 is a VAP, 326 is an encoder, and control is performed so that the control signal 320 and the output signal of the angular displacement encoder 326 become equal. As a result, the control signal 320 is transmitted to the encoder 3.
It acts to match the output of 26.

In the VAP 306 driven by a servo mechanism using such a voice coil motor or the like, in order to improve followability to the control signal 320, phase lead / lag compensation, velocity feedback compensation, etc., which are general methods of servo control, are performed. The frequency characteristic is improved by using the setting of the loop gain, and in this case, the gain may increase up to the frequency that is the unnecessary band. Then, there is a frequency point where the driving sound becomes loud in this unnecessary band. Therefore, the drive signal is a discrete signal or its smoothed signal (PWM
Signal, D / A converter output)
The driving sampling is set to a frequency with a low gain (hard to generate driving noise) as the signal output period.

Next, the processing operation on the microcomputer in this embodiment will be described with reference to the flow charts of FIGS. 4 (a) and 4 (b).

First, FIG. 4A is a flow chart relating to the calculation of a shake angle displacement signal for controlling the drive of an image correction means such as VAP. [Step 401] The angular velocity signal from the angular velocity detecting means 1 is taken in by the A / D converter 4 via the HPF 2 and the amplifier 3. [Step 402] The angular velocity signal captured in step 401 is stored in the RAM. [Step 403] The HPF calculation coefficient is read. [Step 404] The input angular velocity signal of step 401 is multiplied by the HPF calculation coefficient.

The store of the angular velocity signal in step 402 may be performed by HPF calculation. In this case, the offset is removed in advance, which is convenient for detecting the imaging state such as panning detection, vibration frequency detection, and amplitude detection. [Step 405] The integration calculation coefficient is read. [Step 406] The angular velocity signal subjected to the HPF calculation in step 404 is converted into an angular displacement signal by the calculation using the integration coefficient. [Step 407] The angular displacement signal is stored. [Step 408] The phase and gain correction coefficients are read. [Step 409] The angular displacement signal obtained in step 407 is subjected to correction calculation according to the judgment of the vibration frequency / amplitude and the photographing state. [Step 410] The gain coefficient is read. [Step 411] Gain calculation is performed. [Step 412] The control signal obtained in step 409 is converted into an analog value by a D / A converter (not shown), or is output from the microcomputer as a pulse output such as PWM. [Step 413] A series of operations ends.

Next, FIG. 4B is a flow chart of processing relating to vibration frequency / amplitude detection, pan / tilt and photographing state detection, setting of respective calculation coefficients and the like. [Step 415] The angular velocity signal stored in step 402 is read. [Step 416] The angular displacement signal stored in step 407 is read. The order of this step 415 and the previous step 416 does not matter. [Step 417] The shake center frequency and amplitude applied to the device are detected by inputting the angular velocity signal and the angular displacement signal of the above steps 415 and 416.

The swing amplitude is VA driven by the servo mechanism.
The image correction means for P or the like is effective for correction processing when the servo characteristic is deteriorated (reduction of the follow-up amplitude) with a small amplitude (for example, gain is set and changed according to the shake amplitude). [Step 418] The pan / tilt and the photographing state are determined by inputting the angular velocity signal and the angular displacement signal of steps 415 and 416, and the shake center frequency and amplitude detected in step 415. [Step 419] The HPF calculation coefficient and the integral calculation coefficient of the HPF calculation coefficient are set based on the determination result of the pan / tilt and the photographing state. Further, the frequency correction coefficient is set based on the shake center frequency and amplitude obtained in step 417. [Step 420] The initial gain coefficient is read. [Step 421] The gain is set. [Step 422] A series of operations ends.

In this embodiment, when switching the operation / non-operation of the image stabilization function, the image correction amount is gradually changed according to the set value, so that the smooth switching operation becomes possible. As a result, it is possible to reduce the uncomfortable feeling of the photographer during the image stabilization operation.

(Second Embodiment) FIG. 5 is a block diagram showing the structure of a shake correction apparatus according to a second embodiment of the present invention. The same parts as those in FIG. Omit it.

In FIG. 5, the signals to the means (4 to 7) for calculating the angular displacement for controlling the drive of the image correction means 9 have the minimum necessary phase delay because the phase characteristics become a problem. It is desirable to configure it. On the other hand, depending on how the signals to the means (10, 11) for panning (tilting) detection, vibration frequency / amplitude detection, and imaging state determination are processed, if the amplitude level is large, the phase characteristic becomes a problem. I won't.

Therefore, the signal to the means for calculating the angular displacement for controlling the drive of the image correcting means 9 is the signal to the means for detecting the panning (tilting), the vibration frequency / amplitude, and the photographing condition. LPF used for noise removal
It becomes possible to cut off at a lower frequency by using the ones having different bands, and panning (tilting) detection,
It is possible to suppress the noise level of the signal to the means for determining the photographing state such as the vibration frequency / amplitude detection.

Further, by constructing the digital filter like the LPF 14 and providing it inside the microcomputer, it can be realized without cost.

Next, the processing operation on the microcomputer in this embodiment will be described with reference to the flow charts of FIGS. 6 (a) and 6 (b).

First, FIG. 6A is a flow chart relating to the calculation of a deflection angle displacement signal for controlling the drive of an image correcting means such as a variable apex prism (VAP). [Step 601] The angular velocity signal from the angular velocity detecting means 1 is taken in by the A / D converter 4 via the HPF 2 and the amplifier 3. [Step 602] The HPF calculation coefficient is read. [Step 603] The input angular velocity signal of step 601 is multiplied by the HPF calculation coefficient. [Step 604] The integration calculation coefficient is read. [Step 605] The angular velocity signal subjected to the HPF calculation in step 603 is converted into an angular displacement signal by the calculation using the integration coefficient. [Step 606] The angular displacement signal is stored. [Step 607] The phase and gain correction coefficients are read. [Step 608] The angular displacement signal obtained in step 605 is subjected to correction calculation according to the judgment of the vibration frequency / amplitude and the photographing state. [Step 609] The control signal obtained in the above step 608 is converted into an analog value by a D / A converter (not shown) (not shown), or is output from the microcomputer as a pulse output such as PWM (not shown). [Step 610] The LPF calculation is performed on the angular velocity signal taken in by the A / D converter 4 in the step 601 or the angular velocity signal subjected to the HPF calculation in the step 603. [Step 611] The angular velocity data obtained by the process of step 610 is stored. [Step 612] A series of operations ends.

Next, FIG. 4B is a flow chart of processing relating to vibration frequency / amplitude detection, pan / tilt and photographing state detection, setting of each calculation coefficient, and the like. [Step 614] The angular velocity signal stored in step 611 is stored. [Step 615] The angular displacement signal stored in the above step 606 is read. The order of this step and the previous step 614 does not matter. [Step 616] The shake center frequency and amplitude applied to the device are detected by inputting the angular velocity signal and the angular displacement signal of the above steps 614 and 615.

The shake amplitude is VA driven by the servo mechanism.
The image correction means for P or the like is effective for correction processing when the servo characteristic is deteriorated (reduction of the follow-up amplitude) with a small amplitude (for example, gain is set and changed according to the shake amplitude). [Step 617] The pan / tilt and the photographing state are determined by inputting the angular velocity signal and the angular displacement signal of the steps 614 and 615, and the shake center frequency and the amplitude detected in the step 616. [Step 618] The HPF calculation coefficient and the integration coefficient are set based on the determination result of the pan / tilt and the shooting state.
Further, the frequency correction coefficient is set based on the shake center frequency and amplitude obtained in step 616. [Step 619] A series of operations ends.

According to this embodiment, it is possible to suppress the noise level of the signal to the means for performing the panning (tilting) detection, the vibration frequency detection, the amplitude detection, and the photographing state determination, which are relatively susceptible to noise, False detection can be suppressed even if the detection capability is increased.

(Third Embodiment) FIG. 7 is a block diagram showing the structure of a shake correcting apparatus according to a third embodiment of the present invention. The same parts as those in FIG. Omit it.

As shown in FIG. 1, in the case where the gain of the amplifier 3 is fixed, 1 LSB of the angular velocity signal when the microcomputer is loaded
When the hit detection sensitivity is increased, there is a contradictory drawback that the dynamic range is narrowed. When an A / D converter having a relatively low resolution is used, if the detection sensitivity of the angular velocity signal is increased, the amplifier will be saturated at high frequency and large amplitude. If the detection sensitivity is increased, it will be low. There is a situation where the resolution is insufficient due to the frequency and small amplitude. Even this
In a normal case, it is not a problem by properly setting it, but when a special environment (on a vehicle, etc.) is assumed, a high-frequency / large-amplitude signal is likely to be generated, which causes saturation of the amplifier.

In order to solve this, it is possible to use a high resolution A / D converter, but it is relatively expensive and
Currently, a general-purpose one-chip microcomputer has a resolution of about 8 to 10 bits. Further, as shown in FIG. 8, due to the difference in 4-bit resolution, a saturation limit of 1 decade or more can be generated in terms of frequency when a constant amplitude is applied.

Therefore, as shown in FIG. 7, gain control is performed by the gain control means 15 before and after the A / D converter 4, so that the A / D converter with a low resolution such as a built-in microcomputer has a sufficient resolution. It is possible to prevent the saturation of the amplifier while maintaining

In FIG. 7, the gains of the amplifiers 3 and 16 and the output value of the amplifier 16 are monitored so that the gains set in the amplifiers 3 and 16 do not saturate while keeping the resolution as high as possible. , Gain control 1
5 is controlled.

This method is characterized in that it is relatively inexpensive and a wide dynamic range can be obtained, but on the other hand, there is the problem that adjustment of the analog section is relatively difficult and noise peculiar to range switching is likely to occur. However, when used in the configuration shown in FIG. 7, noise is removed (the gain is reduced at high frequencies) by the integrating means 6 and the like, so that it is relatively easy to realize.

At this time, the following processing is performed by the microcomputer. 1) Offset voltage correction The offset voltage generated in the A / D converter and the analog circuit in the preceding stage causes a discontinuity at the time of switching. To prevent this discontinuity, the offset voltage of the input signal is relative. Adjust to zero and write to EEPROM or the like. 2) Gain error correction Similarly, the relative error of the gain generated in the analog stage is measured so that the gains of both are the same. 3) Switching control In switching from a large signal to a small signal, a delay time is provided in order to reduce the number of switching for the purpose of reducing noise.

(Fourth Embodiment) FIG. 9 is a block diagram showing the structure of a shake correction apparatus according to a fourth embodiment of the present invention. The same parts as those in FIG. Omit it.

FIG. 9 shows a floating type A / D converter which uses two A / D converters and performs switching in accordance with the input signal level.

The large signal A / D converter 17 and the small signal A / D converter 19 amplified four times by the amplifier 18 are processed by the gain correction means 20, the gain adjusting amplifier 23 and the offset cancel 21. Offset voltage correction and gain error correction are performed, and the above-mentioned object is achieved by controlling the switch 22 according to the input amplitude, frequency and the like.

(Fifth Embodiment) FIG. 10 is a block diagram showing the structure of a shake correction apparatus according to a fifth embodiment of the present invention. The same parts as those in FIG. Omit it.

As the configuration, the amplifier 3 for the angular velocity signal is used.
, Has a phase advance means, or has means for changing the characteristics thereof arbitrarily. FIG. 11 shows a specific configuration example. Phase advancing means is provided at the front stage of the A / D converter 4 or at the rear stage of the D / A converter (not shown).
LPF2 installed after the converter and before the D / A converter
5 is used to perform gain / phase correction of the shake correction apparatus. The gain is corrected by the amplifier 24.

As an effect, since the quantum error increases when the phase advance calculation is performed inside the microcomputer, the phase is sufficiently advanced by the external analog circuit, and the phase correction is performed by changing the cutoff frequency of the LPF installed inside the microcomputer. By performing the above, it is possible to suppress the quantum error, and it is effective against noise.

(Modification) In the present invention, the angular velocity means is used as the shake detection means, but the angular acceleration means, the acceleration means, the speed means, the angular displacement means, the displacement means, and the method for detecting the image shake itself. Any type such as shake can be detected may be used.

In the present invention, a variable apex angle prism is taken as an example of the image correcting means. However, a light flux changing means such as a shift optical system for moving an optical member in a plane perpendicular to the optical axis, or a vertical optical axis. Any device that can prevent shake, such as one that moves the shooting surface within the plane, and one that corrects shake by image processing, may be used.

Further, the present invention can be applied to photographing devices such as single-lens reflex cameras, lens shutter cameras, video cameras and the like. Further, it can be applied to other optical devices, other devices, and even a constituent unit.

Furthermore, the present invention may be constructed by appropriately combining the above-described embodiments or their techniques.

[0079]

As described above, according to the present invention,
When switching the operation / non-operation of the image correction unit, the image correction amount changing unit changes the image correction amount over a predetermined time.

Therefore, the operation / non-operation of the image correction means is smoothly switched, and the user does not feel uncomfortable during the shake correction operation.

Further, according to the present invention, the low-pass filter is provided only between the angular velocity detecting means and the second means, which is relatively susceptible to noise.

Therefore, it is possible to reduce the noise level to the means for detecting the operating state of the optical equipment in which the apparatus is mounted, and suppress the erroneous detection even if the detection capability here is increased.

Further, according to the present invention, the first amplifying means for amplifying the angular velocity signal from the angular velocity detecting means to an appropriate sensitivity while monitoring the output of the second amplifying means for outputting to the digital computing means.
The gains of the amplifying means and the second amplifying means are controlled.

Therefore, even if the A / D conversion means of relatively low cost and low resolution is used, it is possible to secure both the dynamic range and the high resolution for the input angular velocity signal.

Further, according to the present invention, the phase is sufficiently advanced on the input side of the circuit portion constituted by the microcomputer, and the cutoff frequency of the low pass filter (LPF) arranged in the microcomputer is set. The phase correction is performed by the change to suppress the quantum error.

Therefore, noise in the high frequency range can be suppressed.

Further, according to the present invention, when the drive signal is a discrete signal or a smoothed signal thereof and the optical correction means is controlled by the signal, control for setting the output cycle of the signal to a frequency with a low gain Means are provided to prevent the gain in the unwanted frequency range from increasing.

Therefore, it is possible to suppress the generation of drive noise of the optical correction means in the shake correction operation.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a shake correction apparatus according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view showing the structure of a variable apex angle prism as an example of the image correction means in FIG.

FIG. 3 is a block diagram showing a control system of the variable apex angle prism shown in FIG.

FIG. 4 is a flowchart showing an operation of the shake correction apparatus according to the first embodiment of the present invention.

FIG. 5 is a block diagram showing a configuration of a shake correction apparatus according to a second embodiment of the present invention.

FIG. 6 is a flowchart showing the operation of the shake correction apparatus according to the second embodiment of the present invention.

FIG. 7 is a block diagram showing a configuration of a shake correction apparatus according to a third embodiment of the present invention.

FIG. 8 is a diagram showing a relationship between a frequency and an output of an angular velocity sensor.

FIG. 9 is a block diagram showing a configuration of a shake correction apparatus according to a fourth embodiment of the present invention.

FIG. 10 is a block diagram showing a configuration of a shake correction apparatus according to a fifth embodiment of the present invention.

FIG. 11 is a circuit diagram showing a specific configuration example of the amplifier 3 in FIG.

FIG. 12 is a block diagram showing a configuration of a conventional shake correction apparatus.

FIG. 13 is a flowchart showing an operation of a conventional shake correction apparatus.

[Explanation of symbols]

 1,1 'Angular velocity detecting means 2,2' HPF 3,3 'Amplifier 4,4' A / D converter 5,5 'HPF 6,6' Integrating means 7,7 'Phase and gain correcting means 9,9' Image correction means 10, 10 'Pan / tilt and shooting state determination means 11, 11' Frequency and amplitude detection means 12 Initial control device 14, 14 'LPF 15, 15' Gain control means 20, 20 'Gain correction means 26 IS switch

Claims (6)

[Claims] 1. A vibration detection means for detecting vibration, an image correction means, and a control means for driving the image correction means based on the output of the vibration detection means to remove the influence of the vibration on the image. In a shake correction apparatus provided, a selection unit for selecting an operation state of the image correction unit, and operation / non-operation of the image correction unit in response to the selection state of the selection unit, and at the time of the switching, a predetermined time An image correction amount changing unit for changing the correction amount of the image correction unit with respect to the signal output from the vibration detection unit is provided. 2. The shake correction apparatus according to claim 1, wherein the image correction amount changing unit is a unit that simultaneously changes each correction axis of the image correcting unit. 3. An angular velocity detecting means for detecting vibration, an image correcting means, and a control means for driving the image correcting means based on the angular velocity detecting means to remove the influence of the vibration on the image. In the shake correction device, the control means includes first means for generating a drive signal for the image correction means from an output from the angular velocity detection means, and an optical device on which the device is mounted based on an output from the angular velocity detection means. Second operating means for detecting an operating state of the driving means and correcting the drive signal generated by the first means, and a low frequency band is provided between the angular velocity detecting means and the second means. A shake correction device having a pass filter. 4. An angular velocity detecting means for detecting vibration, a first amplifying means for amplifying an angular velocity signal from the angular velocity detecting means to an appropriate sensitivity, an image correcting means, and a digital operation of an input signal to obtain the image. Digital calculating means for generating a driving signal for the correcting means, A / D converting means for A / D converting the output of the first amplifying means, and amplifying the output of the A / D converting means for the digital calculating means. A shake correction apparatus comprising: a second amplifying means for outputting to the first amplifying means, and a gain control means for controlling the gains of the first and second amplifying means while monitoring the output of the second amplifying means. A shake correction device characterized by being provided. 5. An angular velocity detecting means for detecting vibration, an amplifying means for amplifying an angular velocity signal from the angular velocity detecting means to an appropriate sensitivity, and an A / D for A / D converting an output of the amplifying means.
The conversion means, the image correction means, and the digital calculation means for digitally calculating the output from the amplification means to generate a drive signal for the image correction means, and the output of the digital calculation means are D / A converted, In a shake correction apparatus including a D / A conversion unit that outputs as a drive signal of an image correction unit, a D / A conversion unit is provided before the A / D conversion unit, or
The shake correction is characterized in that a phase advance means is provided after the A conversion means, and a low pass filter is provided after the A / D conversion means or before the D / A conversion means. apparatus. 6. A vibration detection means for detecting vibration, an optical correction means, and a drive signal generated by an output from the vibration detection means, and the optical correction means is driven based on the drive signal to drive the optical correction means. In a shake correction apparatus including a control unit that removes the influence of vibration on an image, the control unit is configured such that the drive signal is a discrete signal or a smoothed signal thereof, and the optical correction unit is controlled by the signal. In this case, the shake correction device is means for setting the output cycle of the signal to a frequency with a low gain.