JPH06265962A - Camera-shake correction device - Google Patents

Abstract

PURPOSE:To suppress the deterioraion of camera-shake correcting performance accompanied the change of temperature. CONSTITUTION:A temperature detection means 12 detecting the temperature around a vibration detection means (angular velocity detection means) 1 and a frequency characteristic control means (characteristic arithmetic means) 13 controlling frequency characteristic change means 5, 6, 7, 10 and 11 according to a signal outputted from the detection means 12 and a signal outputted from the detection means 1 are provided. By the control means 13, the temperature is compensated by controlling (correcting) the change of a frequency characteristic (gain characteristic and phase characteristic) by using the change means 5 according to temperature information obtained by the detection means 12 and shake information detected by the detection means 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention comprises vibration detection means such as angular velocity detection means and image shake correction means such as a variable apex angle prism, and the influence of vibration applied to optical equipment such as a photographing apparatus equipped with the apparatus. The present invention relates to an improvement of a shake correction device that functions to eliminate the above.

[0002]

FIG. 22 shows a circuit configuration of a conventional shake correction device.

Reference numeral 801 is an angular velocity detecting means such as a vibration gyro which constitutes a vibration detecting means, and is attached to, for example, a photographing device. Reference numeral 802 denotes a DC cut filter (or a high-pass filter that cuts off a signal in an arbitrary band) that cuts off the DC component of the angular velocity vibration output from the angular velocity detector 801. An amplifier 803 amplifies the angular velocity signal to an appropriate sensitivity.

804, 805, 806, 807, 81
Reference numerals 0 and 811 denote an A / D converter, an HPF, an integrating means, a phase and gain correcting means, a pan / tilt and photographing state determining means, and a frequency detecting means, for example, by a microcomputer (hereinafter referred to as a microcomputer). Will be realized.

The A / D converter 804 converts an input angular velocity signal into a digital value, and a high-pass filter (hereinafter referred to as HPF) 805 cuts off the digitized angular velocity signal in an arbitrary frequency band, The integrating means 806 at the next stage converts the angular velocity signal into an angular displacement signal. Further, the judging means 810 judges the pan / tilt and the photographing state using the angular velocity signal after A / D conversion and the angular displacement signal output from the integrating means 806, and changes the characteristic of the HPF 805 based on the judgment result. To do. Further, the frequency detecting means 811 receives the angular velocity signal as an input and detects the center frequency of the shake to be corrected, and the phase and gain correcting means 807 corrects the phase and the gain by the detected frequency, and the correction is performed. The angular displacement signal subjected to D / A
It is converted into an analog value by a converter (not shown in FIG. 22) or is output from the microcomputer as a pulse output such as PWM.

Reference numeral 808 denotes a drive circuit, which drives an image correcting means 809 such as a variable apex angle prism based on the displacement signal output from the microcomputer so as to suppress shake.

[0007]

As shown in FIG. 22, the shake applied to, for example, an image pickup apparatus equipped with the shake correction apparatus, that is, the center frequency of the shake to be corrected is detected, and the detected center frequency is detected. A method for changing the gain characteristic and the phase characteristic to correct the gain deviation and the phase deviation of the center frequency of the shake has already been proposed, but in the prior art, the compensation for the temperature characteristics of each element of the shake correction apparatus is made. Was not considered. However, the angular velocity detection means 801
Even when considering only a single vibration gyro, which is normally used as above, there is a considerable variation in frequency characteristics due to temperature.

Therefore, there is a problem in that the performance of vibration suppression of the conventional shake correction apparatus deteriorates due to the change in the characteristics of the element due to the temperature.

Next, another problem to be solved by the present invention will be described.

FIG. 23 is a basic block diagram showing a conventional technique.

Since the present system basically independently controls two camera shake quadrature component signals such as horizontal and vertical applied to the photographing apparatus, only one signal path will be described here.

Reference numeral 901 denotes a vibration gyro which is a vibration detecting means and outputs an angular velocity signal 902. 903
Is an HPF for removing a component close to direct current contained in the angular velocity signal 902, and outputs a camera shake signal 904 having a frequency of about 1 Hz or higher. 905 is an integrating circuit,
The camera shake signal 904 is integrated and an angular displacement signal 906 is output. This angular displacement signal 906 indicates the direction in which the imaging device is facing.

Reference numeral 907 denotes a variable apex angle prism, the apex angle of which is changed by the mechanical driving force generated by the actuator 908 to change the incident light angle to the lens 909, and the changed light flux 910 is on the CCD 911 surface. An image is picked up, and photoelectrically converted here to output an image pickup signal 912.

Reference numeral 913 is an apex angle sensor, which detects the apex angle of the variable apex angle prism 907 and outputs an apex angle signal 914. Reference numeral 915 is an adder circuit which outputs the difference signal 916 obtained by adding the apex angle signal 914 and the above-mentioned angular displacement signal 906 with opposite polarities, and the difference signal 916.
The signal is amplified in 17 and supplied as a drive signal 919 to the actuator 908 via a drive circuit 918.

That is, the actuator 908, the apex angle sensor 913, and the drive circuit 918 form a closed loop. With this configuration, control is performed so that the difference signal 916 of the adder circuit 915 is always zero,
As a result, the apex angle signal 914 acts to match the angular displacement signal 906.

At the time of performing control at the time of panning and starting at the time of turning on the power, if the above-mentioned basic control alone is used, an uncomfortable image will be captured.

Therefore, a system controller 920 is provided, and referring to the values of the angular velocity signal 902 and the difference signal 916, the frequency characteristic of the HPF 903 and the frequency characteristic of the integrating circuit 905 are set in the non-vibration direction as shown in FIG. Vary (decrease anti-vibration performance). Further, when returning, the frequency characteristics of the HPF 903 and the integrating circuit 905 are gradually changed in the direction of image stabilization (improvement of image stabilization performance). In fact, from the system controller 920
The frequency characteristic control signal 921 is output to the HPF 903, and the frequency characteristic control signal 922 is output to the integrating circuit (LPF) 905 to change the frequency characteristics.

In FIG. 23, reference numeral 923 is a selection member for deciding whether or not (ON / OFF) the anti-vibration function is to be actuated, and 924 is a variable vertical angle prism 907 mechanically fixed when the anti-vibration function is not activated. It is a lock motor for operating.

By performing the above-mentioned control, it is possible to obtain vibration proof according to the situation, and stable control is possible.

However, in the above-described conventional shake correcting apparatus, when the photographing apparatus equipped with the shake correcting apparatus is taken out from the indoor to the slope in the ski resort (or from the slope to the indoor) However, since a rapid temperature change occurs, there is a risk that, for example, the variable apex angle prism 907 at the position where the image correction means appears may move separately from the image stabilization. This is because the vibration detecting means such as the vibration gyro used in the above conventional apparatus includes an unstable element having a DC drift with respect to thermal shock.

FIG. 25 shows the measurement result of the DC drift amount with respect to the temperature change. Here, three examples are shown as the number of samples.

Therefore, when a sudden temperature change occurs,
In many cases, the angular velocity signal 902 is overlapped with a DC drift and a signal is output. In this case, HP that influences the vibration isolation performance
When the F903 and the integration constant of the integrating circuit 905 are used as usual, it is difficult to distinguish the angular velocity signal 902 and the DC drift, and therefore the influence of the DC drift remains, and a false camera shake signal (hereinafter, a false signal) is output after the integration. Will end up. Therefore,
Although the image capturing apparatus is not vibrating, there is a problem that the variable apex angle prism 907 is driven by the false signal and the screen moves.

(Object of the Invention) A first object of the present invention is to provide a shake correction apparatus capable of suppressing deterioration of the shake correction performance due to temperature change.

A second object of the present invention is to provide a shake correction device capable of preventing malfunction due to a sudden change in temperature and always performing appropriate image shake correction.

[0025]

According to the present invention, a temperature detecting means for detecting the temperature around the vibration detecting means, and a frequency characteristic change according to an output signal of the temperature detecting means and an output signal of the vibration detecting means. Frequency characteristic control means for controlling the means is provided, and the frequency characteristic changing means uses the frequency characteristic changing means according to the temperature information obtained by the temperature detecting means and the shake information detected by the vibration detecting means. Temperature compensation is performed by adding control (correction) to changes in frequency characteristics (gain characteristics and phase characteristics).

Further, according to the present invention, the temperature detecting means for detecting the temperature around the vibration detecting means, and the frequency characteristic for controlling the frequency characteristic changing means according to the amount of change in the temperature detected by the temperature detecting means. A control means is provided, and the frequency characteristic control means changes the cutoff characteristic in the low frequency range of the output signal of the vibration detection means by using the frequency characteristic change means according to the amount of change in temperature detected by the temperature detection means. Is controlled to eliminate the influence of the DC drift component generated in the vibration detecting means when the temperature changes abruptly.

[0027]

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 construction of a shake correction apparatus according to the first embodiment of the present invention. In FIG. 1, reference numeral 1 is an angular velocity detecting means such as a vibrating gyro, which is used in an optical device such as a photographing apparatus. Installed. Reference numeral 2 is a DC cut filter (or an HPF) that blocks a DC component of the angular velocity signal output from the angular velocity detecting means 1 (or a signal that blocks a signal in an arbitrary band). An amplifier 3 amplifies the input angular velocity signal to an appropriate sensitivity.

Reference numeral 4 denotes an A / D converter for converting an input angular velocity signal into a digital value, and 5 has a function of varying characteristics in an arbitrary band, and removes a low frequency component of the angular velocity signal in an arbitrary band. HPF and 6 are integrating means for converting the angular velocity signal through the HPF 5 into an angular displacement signal. 10 is A
Using the angular velocity signal after the D / D conversion and the angular displacement signal output from the integrating means 6, the pan / tilt and the photographing state are determined,
Based on the result of this judgment, a judgment means for changing the characteristics of the HPF 5, 11 is a frequency detection means for inputting an angular velocity signal, and detects a center frequency of shake to be corrected, 12 is a temperature detection means for temperature detection, and 13 is a temperature detection means. Characteristic calculating means for calculating the correction amounts of the phase and the gain by inputting the detected frequency of the frequency detecting means 11 and the detected temperature of the temperature detecting means 12, and 7 is provided from the integrating means 6 based on the information from the characteristic calculating means 13. It is a phase and gain correction means for correcting the phase and gain of the angular displacement signal.

The A / D converter 4, HPF 5, integrating means 6, phase and gain correcting means 7, pan / tilt and photographing state determining means 10, frequency detecting means 11, and characteristic calculating means 13 are, for example, microcomputers. Is realized by
The angular displacement signal corrected by the phase and gain correction means 7 is converted into an analog value by a D / A converter (not shown in FIG. 1) or as a pulse output such as PWM. It is output from the microcomputer.

Reference numeral 8 is a drive circuit, which drives the image correction means 9 so as to suppress shake based on the displacement signal output from the microcomputer.

Here, as the above-mentioned image correction means 9, for example, those shown in FIGS. 10 to 16 are representatively mentioned.

FIGS. 10 to 13 show an example of the image correction means 9 in which a variable apex angle prism is used, a voice coil is used as a drive system, and closed loop control is performed by an angular displacement encoder. is there.

First, the variable apex angle prism will be described in detail.

As shown in FIG. 12, the variable apex angle prism 3
06 is two transparent parallel plates 340a and 340b facing each other.
A transparent elastic body having a high refractive index (refractive index n) or an inert liquid 342 is sandwiched between them, and the outer periphery thereof is elastically sealed by a sealing material 341 such as a resin film, which is transparent and parallel. Board 34
0a and 340b are configured to be swingable.

FIG. 13 shows a variable vertical angle prism 30 of FIG.
6 one of the transparent parallel plates 340a is attached to the swing shaft 301 (31
Incident light flux 34 when rotated by angle σ around 1)
It is the figure which showed the passing state of No. 4.

As shown in the figure, the light beam 344 incident along the optical axis 343 is deflected by the angle φ = (n−1) σ and emitted by the same principle as that of the wedge prism. That is, the optical axis 343 is decentered (deflected) by the angle φ.

Returning to the explanation of FIG. 10, reference numeral 302 denotes a lens barrel for fixing the variable apex angle prism 306 described above so as to be rotatable around the swing shafts 301 and 311 via the holding frame 307. .

313 is a yoke, 315 is a magnet, 3
Reference numeral 12 denotes a coil, which constitutes a voice coil type actuator, and by passing a current through the coil 312, the variable apex angle prism 30 with the swing shaft 311 as the center.
The apex angle of 6 can be varied.

Reference numeral 310 denotes a slit which moves in the same manner as the swing shaft 311, 308 a light emitting diode, and 309 a PSD (Positi).
on Sennsinng Detector), which constitutes an encoder for detecting the angular displacement of the apex angle of the variable apex angle prism 306.

Reference numeral 303 is a lens for forming an image of the light flux whose incident angle is changed by the variable apex angle prism 306 on the surface of the CCD 304.

Reference numeral 305 denotes the other swing shaft.

FIG. 11 shows a variable apex angle prism (V
FIG. 3 is a block diagram showing a basic configuration for driving and controlling an AP) 306.

In FIG. 11, 322 is an amplifier and 322.
Is a driver, 324 is an actuator, and 325 is an encoder that detects angular displacement.

With the above configuration, the control signal 320
Since the control works so that the output signal of the encoder 325 becomes equal to the output signal of the encoder 325, as a result, the control signal 320 works so as to match the output of the encoder 325.

14 and 15 show another example of the image correction means 9, and the same parts as those in FIG. 10 are designated by the same reference numerals.

As an example of the image correcting means 9, here is shown an example in which the variable apex angle prism 306 described above is used and a stepping motor is used as means for driving the variable apex prism 306. As a center of rotation, the stepping motor 401 drives the variable apex angle prism 306 via the holding frame 307. In addition,
In FIG. 14, a reset sensor 402 detects the reference position of the variable apex angle prism 306.

FIG. 15 is a block diagram showing the basic structure for driving and controlling the variable apex angle prism 306.

In FIG. 15, reference numeral 410 denotes a drive arithmetic circuit,
Reference numeral 411 denotes a driver, and when the control signal 320 is input, the drive operation circuit 410 performs drive operation and outputs it to the driver 411. Then, the driver 41
Reference numeral 1 drives the stepping motor 401 to change the apex angle of the variable apex angle prism 306.

FIG. 16 shows, as an example of the image correction means 9, a memory control system, which is constructed so that a part of a prepared image signal can be cut out and enlarged. In this method, the cut-out position of the video signal is moved according to the shaking motion.

In FIG. 16, 100 is a zoom lens,
Reference numeral 101 is an image sensor (CCD) that converts an optical image into an electric signal.
And 102 is an A / D converter. 1
03 is an input control signal (runout signal) 32
It is a correction processing means for taking out predetermined image information from the feed memory 108 and enlarging the entire image so as to reduce the shake component of the image pickup signal based on 0. 1
Reference numeral 04 is an interpolation processing means for interpolating one pixel signal from image information of two or more adjacent pixels by zoom information.
Reference numeral 5 is a D / A converter, and 107 is an encoder for detecting the zoom magnification ratio of the zoom lens 100.

To explain the operation of the above configuration, the optical image passing through the zoom lens 100 is converted into an electric signal by the image pickup element 101, and the image pickup signal is converted into a digital signal by the A / D converter 102.

The correction processing means 103 which receives this signal,
Image information for one field is written in the memory 106 via the memory control unit. Then, the image signal is read from the field memory 108 by the input control signal 320 and the zoom information from the encoder 107,
It is output to the interpolation processing means 104. Interpolation processing means 104
In order to convert the signal read from the field memory 108 and input into the original size of the scanning width of the output image according to the cutout size, how many pixels are to be output in the normal one pixel output period. Is calculated and interpolation processing is performed. Next D /
The A converter 105 converts the interpolated digital signal into an analog signal and outputs it.

As described above, various kinds of image correcting means 9 can be cited.

Next, the processing operation on the microcomputer of the shake correcting apparatus according to the first embodiment of the present invention shown in FIG. 1 will be described with reference to the flowchart of FIG. [Step 201] DC cut filter 2, amplifier 3
The angular velocity signal from the angular velocity detecting means 1 via is taken in via the A / D converter 4. [Step 202] Based on the angular velocity signal from the A / D converter 4 and the angular displacement signal from the integrating means 6, the determining means 10 determines the pan / tilt and the photographing state. [Step 203] A coefficient that determines the characteristics of the HPF 5 is read according to the result of the pan / tilt and the shooting state. The coefficients according to the pan / tilt and the shooting state are empirically determined. [Step 204] The characteristic of the HPF 5 is changed according to the characteristic coefficient. [Step 205] The output signal of the HPF 5 whose characteristics have been changed and the low frequency component of the angular velocity signal has been removed in an arbitrary band is integrated by the integrating means 6 to be converted into an angular displacement signal (vibration signal). [Step 206] The angular velocity signal is calculated by the frequency detecting means 11 to detect the shake center frequency. [Step 207] The signal obtained by the temperature detecting means 12 is fetched. [Step 208] The phase and gain correction coefficients corresponding to the frequency obtained in the above step 206 and the temperature fetched in the above step 207 are read (in the characteristic calculation means 13). [Step 209] The correction calculation of the phase and the gain is performed with the coefficient obtained in the above step 208 (in the phase and gain correcting means 7). [Step 210] The calculation result obtained in step 209, that is, the corrected angular displacement signal is converted into an analog value by a D / A converter (not shown) (or,
(As a pulse output such as PWM) is output to the drive circuit 8 which drives the image correction means 9.

Here, a method of correcting the phase and the gain will be described below.

Suppose that the sufficient effect of shake correction can be obtained by changing the residual shake component to "-30d" with respect to the applied shake.
If "B" or less can be achieved, it is assumed that this state (sufficient effect of shake correction is obtained). (Because the focal length of the image capturing device has a large effect on the shake correction effect, for example, if the focal length is simply doubled,
The same effect cannot be obtained in an image obtained without the double suppression effect. However, in the overall shake suppression effect including the shake sensor for detecting shake (the angular velocity detecting means 1 in this embodiment) and the image correction system, at present, the amount of residual shake after shake correction is The range that can be suppressed to “−30 dB” can be obtained only in a narrow range as compared to the shake band of the correction target (for example, 1 to 15 Hz).

To show a concrete example, it is assumed that the frequency characteristics obtained by the current angular velocity detecting means 1 and the image correcting means shown in FIG. 10 are as shown in FIG.

That is, FIG. 3 shows the angular velocity detecting means 1 of FIG.
The frequency characteristics of the image correction means 9 are shown with respect to the input of the sine-wave shake applied to the above. The upper diagram shows the gain characteristic, the lower diagram shows the phase characteristic, and the vertical axis shows the gain (upper diagram), phase ( The following figure) is shown, and the horizontal axis represents the frequency (1 to 100 Hz).

An enlarged view of this range is characteristic 1 in FIG.

With respect to this characteristic 1, focusing on the phase, the phases match at 3 Hz, and the HPF5 (here, the cutoff frequency is 0.06 Hz) as the frequencies before and after the phase match toward the low frequency side. Alternatively, the phase advances due to the influence of the integrating means 6 (the cutoff frequency is 0.07 Hz), and the phase is delayed toward the high frequency side due to the influence of the angular velocity detecting means 1 and the image correcting means 9. The gain is 1 to 10
It is almost constant up to about Hz.

The suppression characteristic at this time is the characteristic 6 of FIG. 5, and this FIG. 5 shows the effect of correction on the frequency (horizontal axis) (vertical axis, expressed in dB).

Characteristic 6 shows the residual shake component, which is expressed by 20Log (OUT / IN) OUT: residual shake component after shake correction IN: shake amount.

As can be seen from this characteristic, the best suppression can be achieved at 3 Hz in which the phases match, and 2 to 4 which is the vicinity thereof.
In Hz, the suppression of "-30 dB" is almost achieved,
At 10 Hz, it has a damping effect of about "-18 dB".

In other words, this phase shift causes deterioration of the shake suppression effect.

Here, considering the correction of the phase delay of the characteristic 1, the characteristic having the phase lead element represented by the transfer function of H (S) = a (S + z). If the characteristic is connected in series, the phase can be corrected at a predetermined frequency. It should be noted that this is to set the frequency higher than the range of shake suppression to advance the phase.

This is performed by the phase and gain correction means 7.

For example, focusing on the phase delay at 10 Hz of characteristic 1, it is delayed by about 7.5 deg. Therefore, it can be corrected by advancing the 7.5 deg phase at 10 Hz using the characteristic having the above formula.

That is, the characteristic 2 is to correct the phase shift of the characteristic 1 at 10 Hz (to match the phase and also match the gain). This is z in the above equation
It can be set by (zero). Also, the gain is 0d at 10Hz.
Adjust a to be B.

If these are realized by the phase and gain correction means 7, the characteristic 1 can be changed to the characteristic 5 shown in FIG.

The characteristic showing the damping effect obtained by this is characteristic 7 in FIG. 10Hz at this time from characteristic 7
It can be seen that the best vibration suppression effect can be obtained in the vicinity.

At 20 Hz as well, similarly to the characteristic 1, if the characteristic 4 as shown in FIG. 6 is realized by the phase and gain correcting means 7, the characteristic 5 is obtained. The damping effect realized by this characteristic is characteristic 8 shown in FIG.
The best damping effect is obtained in the vicinity.

In the phase and gain correction means 7,
In order to realize the characteristics of the above equation, a digital filter may be used, and the digital filter at this time is
If a first-order IIR filter is used, 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 a filter coefficient, Filter coefficients a0, a1, a2
Since the frequency characteristic can be set by changing, the data of the filter coefficients a0, a1, and a2 are prepared as a table according to the shake frequency, and the IIR filter operation may be performed by the filter coefficient obtained from the table. .

It should be noted that, as an effect concerning the correction according to the frequency axis, for example, when a handheld image of a video movie is taken, hand shake is distributed in a relatively wide frequency range, but a shake having a relatively large amplitude. Is distributed in a narrow range to some extent depending on the skill level of the photographer and the photographing condition. Therefore, if it can be configured to give the best correction effect to the center band of such shake, the skill level of the photographer, the shooting state (handheld,
Optimum correction is possible according to the conditions such as mounting on a tripod or from the top of the vehicle.

Therefore, the change in the frequency characteristic due to the temperature is measured in advance, and the data of the filter coefficients a0, a1 and a2 corresponding to the temperature and the swing frequency as shown in FIGS. 7 to 9 are prepared as a table. If the calculation is performed using the filter coefficient obtained from the table and the correction is performed, the change in the frequency characteristic due to the temperature can be corrected well.

7 to 9 show the RO in the microcomputer as described above.
It shows the filter coefficient a according to the temperature and shake frequency stored in M, for example, the temperature is 22. C, when the shake frequency is 4 Hz, a0 = a0 ₆₄ , a1 = a1
₆₄ , a2 = a2 ₆₄ are read out, and the correction calculation is carried out accordingly.

(Second Embodiment) FIG. 17 is a block diagram showing the structure of a shake correction apparatus according to the second embodiment of the present invention. The same parts as those in FIG. 1 are designated by the same reference numerals.

In the second embodiment, the HPF 5 also serves as the processing means and the phase and gain correction means at the time of panning, and the judging means 1 for judging the pan / tilt and the photographing state.
0, the signals from the frequency detecting means 11 and the temperature detecting means 12 are input, and the coefficient calculating means 14 calculates the characteristic of the HPF 5.

As a merit, the gain and phase correcting means are not required independently, and the frequency lower than the center frequency of the shake is cut off, so that the operability is improved. (The lower the low-range suppression performance, the better the followability of the shake correction device with respect to the camera, etc., so the operability is better as the cutoff frequency becomes higher.) That is, the center frequency of shake is sufficiently corrected for shake. If the center frequency of shake is high, HP
The cutoff frequency of the low frequency due to F5 is increased, and the operability is improved.

Next, the processing operation on the microcomputer in this embodiment will be described with reference to the flowchart of FIG. [Step 401] DC cut filter 2, amplifier 3
The angular velocity signal from the angular velocity detecting means 1 via is taken in via the A / D converter 4. [Step 402] Based on the angular velocity signal from the A / D converter 4 and the angular displacement signal from the integrating means 6, the determining means 10 determines the pan / tilt and the photographing state. [Step 403] The frequency detecting means 11 calculates the angular velocity signal and detects the shake center frequency. [Step 404] The signal obtained by the temperature detecting means 12 is fetched. [Step 405] A coefficient that determines the characteristics of the HPF 5 from each of the pan / tilt and shooting state information obtained by the determination means 10, the shake center frequency obtained by the frequency detection means 11, and the temperature information obtained by the temperature detection means 12. Read out.

As a method of determining the coefficient at this time, a method of searching a data table based on three pieces of information (values) or a method of comparing respective characteristics and setting a coefficient having a higher cutoff frequency is set. And so on.

Basically, the cutoff frequency of HPF5 obtained from the shake center frequency and the temperature detection result is used as a reference.
At the time of pan / tilt, control is performed so that the cutoff frequency of the HPF 5 goes to a higher frequency side.

The setting of the characteristics according to these coefficients has been empirically obtained. [Step 406] The characteristic of the HPF 5 is changed by the characteristic coefficient. [Step 407] The output signal of the HPF 5 in which the characteristics are changed and the low-frequency component of the angular velocity signal is removed in an arbitrary band is integrated by the integrating means 6 to be converted into an angular displacement signal (shake signal). [Step 408] The corrected angular displacement signal obtained in step 407 is converted into an analog value by a D / A converter (not shown) (or as a pulse output such as PWM), and image correction is performed. Drive circuit 8 for driving the means 9
Output to.

According to the first and second embodiments described above, the phase and gain characteristic changes in the phase and gain correction means 7 are corrected in accordance with the temporal change in temperature, that is, temperature compensation is performed. Therefore, it is possible to prevent the deterioration of the shake correction performance due to the temperature change.

(Third Embodiment) FIG. 19 is a block diagram showing the arrangement of a shake correction apparatus according to the third embodiment of the present invention.

Reference numeral 501 is a vibration gyro which is a vibration detecting means and outputs an angular velocity signal 502. 503
Is an HPF for removing a component close to direct current contained in the angular velocity signal 502, and outputs a camera shake signal 504 having a frequency of about 1 Hz or higher. An integration circuit 505 integrates the camera shake signal 504 to generate an angular displacement signal 506.
Is output. This angular displacement signal 506 indicates the direction in which the image capturing device is facing.

Reference numeral 507 denotes a variable apex angle prism, the apex angle of which is changed by the mechanical driving force generated by the actuator 508 to change the incident light angle to the lens 509, and the changed light beam 510 is reflected on the CCD 511 surface. An image is picked up, and photoelectrically converted here to output an image pickup signal 512.

Reference numeral 513 denotes an apex angle sensor, which detects the apex angle of the variable apex angle prism 507 and outputs an apex angle signal 514. Reference numeral 515 is an adder circuit that outputs the difference signal 516 obtained by adding the apex angle signal 514 and the above-mentioned angular displacement signal 506 with opposite polarities.
The signal is amplified by 17 and is supplied as a drive signal 519 to the actuator 508 via the drive circuit 518.

The actuator 508 and the apex angle sensor 5
13 to the drive circuit 518 form a closed loop. In this configuration, control is performed so that the difference signal 516 of the adder circuit 515 is always zero, and as a result, the apex angle signal 514 is the angular displacement signal. Acts to match 506.

520 periodically takes in an angular velocity signal 502, a differential signal 516, and a temperature signal 526 described later in order to control the present apparatus, and HPF 503 integrates frequency characteristic control signals 521 and 522 which determine the vibration isolation performance according to the conditions described later. It is a system controller that outputs to the circuit 505.

523 indicates whether to activate the image stabilization function (ON
A selection member 524 for determining ON / OFF) is a lock motor for mechanically fixing the variable apex angle prism 507 when the anti-vibration function is not activated.

Reference numeral 525 is a temperature sensor that detects the temperature around (near) the vibrating gyro 510 and outputs a temperature signal 526, which can be easily realized by a semiconductor temperature sensor or the like. (Equipped with two in order to detect horizontal and vertical vibrations of the optical device).

FIG. 20 shows the system controller 520.
2 is a flowchart showing the operation of the above, and will be described below according to this.

When the power of this apparatus is turned on, the system controller 520 starts the operation from step 601. [Step 601] Whether or not an instruction to start the image stabilization function is determined from the state of the selection member 523, and if an instruction to start the image stabilization function is issued, that is, the selection member is O
If it is N, the process proceeds to step 602, and if it is OFF, the process proceeds to step 608. [Step 602] Since the instruction to start the image stabilization function has been issued, the variable apex angle prism (VAP) 507 is brought into a movable state via the lock motor 524. [Step 603] The frequency characteristic control signal 521 is output to the HPF 503 to shift the cutoff frequency to the low frequency side.
Alternatively, the integrating circuit 505 may be formed of an LPF, and the frequency characteristic control signal 522 may be output to shift the cutoff frequency to the low frequency side.

That is, the HPF 503 or the integrating circuit 5
The frequency characteristics of 05 are changed to improve the vibration isolation performance. [Step 604] It is determined whether or not the difference signal 516 has a large value for a long time, and if it is, it is abnormal and therefore the process proceeds to step 609. If not, the process proceeds to step 605. [Step 605] It is determined whether or not the angular velocity signal 502 has a large number of DC components. If the angular velocity signal 502 has a large number of DC components, it is possible that panning has occurred. If the DC component is small, the process proceeds to step 606. [Step 606] It is determined whether or not a rapid change is seen in the temperature signal 526. This can be easily realized by calculating the temporal change rate inside the system controller 120. If an abrupt change is found, go to step 609. Other than that, there is no abnormality, and the process proceeds to step 607. [Step 607] It is checked whether or not the characteristics have the best vibration isolation performance. This is determined by whether or not the frequency characteristic is set in advance. As a result,
If it does not have the best anti-vibration characteristics, step 603
Return to and enter the routine to improve the vibration isolation performance. Also,
If the image stabilization characteristic is the best, the process goes to step 604, which is an abnormality detection routine, and an abnormality waiting state is entered.

If it is determined in step 601 that the image stabilization function has not been started, the process proceeds to step 608 as described above. [Step 608] The lock motor 524 is driven to hold the variable apex angle prism 507 at its movable center.

Further, in step 604, the difference signal 5
16 abnormalities are detected, in step 605 it is detected that the angular velocity signal 502 has many DC components, or in step 6
If it is detected in 06 that a rapid change in temperature is detected, the process proceeds to step 609 as described above. [Step 609] Step 604, Step 6
Since the abnormality check is detected in 05 or step 606, the image stabilization performance is degraded here.

Specifically, the cutoff frequency of the HPF 503 is moved to the higher side. Alternatively, the integrating circuit 505 is composed of an LPF and its cutoff frequency is shifted to a higher side. Or
Passing the angular velocity signal 502 from the vibration gyro 501 to H
You may make it cut off in PF503. [Step 610] The difference signal 516 is checked. If there is an abnormality, the process proceeds to step 613, and if there is no abnormality, the process proceeds to step 611. [Step 611] The DC component of the angular velocity signal 502 is checked, and if there is an abnormality (when there are many DC components), the process proceeds to step 613, and if there is no abnormality, step 612.
Go to. [Step 612] It is checked whether or not there is a rapid change in temperature. If there is a rapid change, step 61
3. If there is no sudden change, go to step 603 to improve the vibration isolation performance. [Step 613] Since it is detected in step 110, 611, or step 612 that the abnormality is still present, the vibration damping performance is assumed to be in the worst state (the variable apex angle prism 507 is stopped in some cases). State). As a result, if it is in the lowest state, the process returns to step 610. Also,
If it is not in the lowest state, the process returns to step 609 in order to reduce the vibration isolation performance.

The above operation is repeated so that the anti-vibration performance can always be used in the best condition, and if any abnormality is confirmed, the anti-vibration performance is reduced and avoided.

(Fourth Embodiment) FIG. 21 is a flow chart showing an abnormality waiting routine according to a fourth embodiment of the present invention. The circuit configuration and the routine other than this abnormality waiting routine are the same as those shown in FIGS. 9 and 20. Since it is the same, it is omitted here.

When a certain time has come, an abnormality waiting routine is entered, and the operation from step 701 is started. [Step 701] The system controller 120 reads the difference signal 516, and confirms whether it is within a predetermined value. If it is within the predetermined range, it is determined to be normal and the process proceeds to step 702. If it is not within the predetermined range, it is determined to be abnormal and the process proceeds to step 704. [Step 702] Temperature signal 5 from temperature sensor 525
26 is read and the degree of temperature change is calculated. [Step 703] The DC component included in the angular velocity signal 502 from the vibration gyro 510 is checked. If the DC component is present for a predetermined time or longer, it is determined to be abnormal and the process proceeds to step 704. Otherwise, it is determined to be normal and the abnormality waiting routine ends. [Step 704] The abnormality waiting routine is skipped, and the routine enters the antivibration performance degrading routine. As in the third embodiment, the HPF 5 is executed.
03 and the frequency characteristics of the integrating circuit 505 are moved in the non-vibration-proof direction.

As described above, even if a rapid temperature change is detected, if the angular velocity signal has few drift components, it is determined to be normal, and the operation is performed so as not to deteriorate the vibration isolation performance.

According to the third and fourth embodiments described above, the cutoff frequency of the HPF 503 and the integrating circuit (LPF) 505 is raised so as to raise the frequency band of the angular velocity signal according to the amount of change in temperature. Therefore, it is possible to promptly avoid a malfunction due to a rapid change in temperature, and the recorded image also has no discomfort.

More specifically, as the temperature changes drastically, a malfunction occurs due to the appearance of DC drift of the vibration gyro 501. With the above-mentioned configuration, the variable apex angle prism 507 is movable with respect to DC drift. Will disappear. Therefore, it is possible to perform more stable image blur correction.

[0105]

As described above, according to the present invention,
Temperature detection means for detecting the temperature around the vibration detection means,
Frequency characteristic control means for controlling the frequency characteristic changing means according to the output signal of the temperature detecting means and the output signal of the vibration detecting means are provided, and the temperature information obtained by the temperature detecting means is obtained by the frequency characteristic controlling means. Control (correction) to change the frequency characteristic (gain characteristic, phase characteristic) using the frequency characteristic changing means according to the shake information detected by the vibration detecting means.
Is added to perform temperature compensation.

Therefore, it becomes possible to suppress the deterioration of the shake correction performance due to the temperature change.

Further, according to the present invention, the frequency characteristic changing means is controlled in accordance with the temperature detecting means for detecting the temperature around the vibration detecting means and the amount of change in the temperature detected by the temperature detecting means. Frequency characteristic control means is provided, and the frequency characteristic control means uses the frequency characteristic changing means in accordance with the amount of change in temperature detected by the temperature detecting means to cut off the low-frequency region of the output signal of the vibration detecting means. Is controlled to eliminate the influence of the DC drift component generated in the vibration detecting means when the temperature changes abruptly.

Therefore, it is possible to prevent a malfunction due to a rapid change in temperature and always perform appropriate image blur correction.

[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 flowchart showing the operation of the microcomputer of FIG.

FIG. 3 is a diagram showing frequency characteristics of an image correction unit with respect to a sinusoidal shake applied to the angular velocity detection unit of FIG.

FIG. 4 is an enlarged view of the range of FIG.

5 is a diagram showing a suppression rate of the frequency characteristic shown in FIG.

FIG. 6 is a diagram showing how the frequency characteristic of FIG. 4 is changed by the phase and gain correction means.

7 is a diagram showing an example of a table of filter coefficient data stored in a ROM in the microcomputer of FIG.

8 is a diagram showing another example of a table of filter coefficient data stored in a ROM in the microcomputer of FIG.

9 is a diagram showing another example of a table of filter coefficient data stored in a ROM in the microcomputer of FIG.

10 is a cross-sectional view showing an example of the image correction means of FIG.

11 is a block diagram showing a drive control system of a variable apex angle prism as the image correction means of FIG.

12 is a side view showing the configuration of the variable apex angle prism shown in FIG.

FIG. 13 is a side view showing a state where one transparent parallel plate is rotated from the state of FIG.

FIG. 14 is a cross-sectional view of a configuration in which a variable apex angle prism as an image correction unit in FIG. 1 is driven by a stepping motor.

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

16 is a block diagram of a case where the image correction means of FIG. 1 is configured by a memory control method.

FIG. 17 is a block diagram showing a configuration of a shake correction apparatus according to a second embodiment of the present invention.

18 is a flowchart showing the operation of the microcomputer of FIG.

FIG. 19 is a block diagram showing a configuration of a shake correction apparatus according to a third embodiment of the present invention.

20 is a flowchart showing the operation of the system controller of FIG.

FIG. 21 is a flow chart showing an abnormality waiting routine of the shake correcting apparatus in the fourth embodiment of the present invention.

FIG. 22 is a block diagram showing an example of the configuration of a conventional shake correction apparatus.

FIG. 23 is a block diagram showing another example of the configuration of the conventional shake correction apparatus.

FIG. 24 is a diagram showing changes in frequency characteristics of the HPF and the integrating circuit in FIG. 23.

FIG. 25 is a diagram showing changes in the amount of DC drift with respect to changes in the temperature of the vibration gyro of FIG. 23.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Angular velocity detecting means 5 HPF 6 Integrating means 7 Phase and gain correcting means 8 Driving circuit 9 Image correcting means 10 Pan / tilt and photographing state judging means 11 Frequency detecting means 12 Temperature detecting means 13 Characteristic calculating means 14 Coefficient calculating means 510 Vibration Gyro 503 HPF 505 Integration circuit (LPF) 507 Variable apex angle prism 520 System controller 525 Temperature sensor

Claims (5)

[Claims] 1. A vibration detecting means for detecting a vibration of an optical device, an image correcting means for correcting an image blur, a vibration frequency detecting means for detecting a vibration frequency applied to the optical device, and an output of the vibration detecting means. A shake correction device including frequency characteristic changing means for changing the frequency characteristic of a signal, and drive means for driving the image correcting means in a direction of suppressing the vibration detected by the vibration detecting means. In, temperature detection means for detecting the temperature around the vibration detection means,
A shake correction apparatus comprising: a frequency characteristic control unit that controls the frequency characteristic changing unit according to an output signal of the temperature detecting unit and an output signal of the vibration detecting unit. 2. The frequency characteristic changing means is means for changing the gain characteristic and the phase characteristic of the output signal of the vibration detecting means,
The frequency characteristic control means is means for controlling the change of the gain characteristic and the phase characteristic performed in the frequency characteristic changing means according to the output signal of the temperature detecting means and the output signal of the vibration detecting means. The shake correction device according to claim 1. 3. A vibration detecting means for detecting the vibration of the optical device, an image correcting means for correcting the image blur, a vibration frequency detecting means for detecting the vibration frequency applied to the optical device, and an output of the vibration detecting means. A shake correction device including frequency characteristic changing means for changing the frequency characteristic of a signal, and drive means for driving the image correcting means in a direction of suppressing the vibration detected by the vibration detecting means. In, temperature detection means for detecting the temperature around the vibration detection means,
Depending on the amount of change in temperature detected by the temperature detecting means,
A shake correction apparatus comprising: a frequency characteristic control unit that controls the frequency characteristic changing unit. 4. The frequency characteristic changing means is means for changing the cutoff characteristic of the output signal of the vibration detecting means in the low frequency range, and the frequency characteristic controlling means changes the temperature change amount detected by the temperature detecting means. 4. The shake correction apparatus according to claim 3, further comprising means for controlling the change of the cutoff characteristic of the output signal of the vibration detecting means in the low frequency range, which is performed by the frequency characteristic changing means. 5. The frequency characteristic changing means is a means for changing the cutoff characteristic of the output signal of the vibration detecting means in the low frequency range, and the frequency characteristic controlling means is for changing the temperature detected by the temperature detecting means. 4. The shake correction apparatus according to claim 3, wherein the shake correction apparatus is means for controlling the frequency characteristic changing means so as to cut off the input of the output signal of the vibration detecting means when the value is larger than the predetermined value.