JP2003131281A - Device for correcting image blurring - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable an image blurring correcting device to detect the abnormality of a vibration detecting means and its output and to perform a proper image blurring correction operation on the basis of a detection result when any abnormality is detected. SOLUTION: This image blurring correcting device has a vibration detecting means for detecting vibrations, a correction voltage outputting means for outputting a correction voltage, a comparing means for comparing the output of the vibration detecting means with the difference of the correction voltage output, and an offset eliminating means for eliminating the offset component of the output of the vibration detecting means by changing the correction voltage output on the basis of the output of the comparing means, and further has an offset elimination abnormality deciding means (#207 to #209 and #215 to #217) for deciding whether abnormality exists in the offset elimination operation by the offset eliminating means, and a controlling means (#210 and #218) for controlling the image blurring correction operation on the basis of the decision results of the offset elimination abnormality deciding means.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in an image blur correction device for compensating for vibration / vibration in a camera, an interchangeable lens, a video movie or the like.

[0002]

2. Description of the Related Art Conventionally, there has been proposed a device for correcting shake of an optical system such as a camera, that is, for suppressing image vibration by hand shake to stabilize an image. A typical one of the shake correction methods used in cameras and the like is to drive part or all of the photographing optical system based on the shake information of the camera detected by the shake sensor to drive the image on the image plane. This is to suppress image blur.

Here, an angular velocity sensor or an acceleration sensor is generally used as the shake sensor.
Since such an angular velocity sensor or acceleration sensor itself outputs only a minute voltage in response to a given vibration, an appropriate amplifier is provided outside the sensor to output a necessary voltage. ing. However, a sensor that detects such vibrations, especially a piezoelectric vibration gyro that is commonly used in cameras, etc., has a static output voltage (the difference between the sensor reference voltage and the static output voltage when the vibration is not applied). (= Null voltage) varies greatly depending on the individual variations of the vibration gyro and changes in the usage environment, especially with the usage temperature. Therefore, especially when the power is turned on, the null voltage is amplified when the output signal is amplified to the required voltage, and the signal saturates especially when a high gain amplifier is used. There was a possibility that it would end up.

In order to solve the above-mentioned problem, as a method conventionally disclosed, a high-pass filter circuit is provided which cuts from the output of the angular velocity sensor a frequency lower than an allowable low frequency with respect to the frequency of vibration to be detected, A method of amplifying a signal that has passed through this high-pass filter circuit by an amplifier is generally taken.

Further, as a further improved type of the above conventional example,
Japanese Unexamined Patent Publication No. 10-228043 discloses a vibration detecting device which eliminates a large-capacity capacitor forming a high-pass filter circuit and is advantageous in terms of cost and mounting. this is,
The output from the vibration gyro is input to a microcomputer through a circuit composed of a low-pass filter circuit, an adder and an amplifier circuit, and the microcomputer determines whether the output signal of the circuit exceeds a predetermined level range or is biased to a reference level. judge. Then, when it is determined that it exceeds the predetermined level range or is biased with respect to the reference level, a control signal is generated from the microcomputer, and the output of the D / A converter is controlled by the signal. The output of the D / A converter is connected to the adder and adjusts the output signal within a predetermined level range and a reference level. With such a configuration, an unstable output when the power is turned on is amplified without being saturated, and a desired output value is obtained. However, in Japanese Patent Laid-Open No. 10-228043, the output control method of the D / A converter is not necessarily efficient.

On the other hand, in the configuration for removing the offset component of the sensor by using the D / A converter, as an example of the configuration proposed by the applicant of the present invention, which enables a more efficient and quick offset removal operation, FIG. 8 shows a conventional example in which the device is applied to an interchangeable lens of a single-lens reflex camera.

FIG. 8 is a block diagram showing a specific circuit configuration of a lens microcomputer and a shake correction system as a lens electric system.

The output from the vibration gyro 1 which is an angular velocity sensor for detecting shake is the resistance R1, the resistance R2 and the resistance R.
3, the condenser C1, the condenser C2, and the amplifier 3 including the operational amplifier 2, and
It is input to the / D converter 5. The amplification factor in the amplification unit 3 is determined by "R3 / R1", and a second-order high-frequency cutoff filter is formed for noise removal. D / A
The conversion unit 7 includes two 8-bit D / A converters (D / A: 71,
D / A: 72) and resistors R4 and R5.
At the output end of the 8-bit D / A converter 71, a resistor R4 is
A resistor R5 is connected to the output end of the bit D / A converter 72, and the other end of both resistors is an operational amplifier 2
It is connected to the non-inverting input terminal of. Here, the resistor R4
The resistance ratio between the resistor R5 and the resistor R5 is, for example, “R4: R5 = 1: 11
It is set to about 0 ”. This is determined in consideration of the resolution of offset removal control.

At the initial stage of power-on, etc., the offset removing circuit 6 operates to calculate the offset component removal of the vibration gyro 1. The offset removal circuit 6 is composed of an output saturation avoidance control unit 61, a control data storage unit 62, and a data selection / control unit 63. First, the output saturation avoidance control unit 61 avoids output saturation. 8bit D / A converter 71 and 8bi with relatively coarse resolution
Controls the output of the t D / A converter 72. This action quickly avoids output saturation.

Next, in order to output an output at an arbitrary level where the output is not saturated to the target value, control data corresponding to the difference between the current output value and the target value is selected from the control data storage unit 62, and the data is selected. The control unit 63 controls the outputs of the 8-bit D / A converter 71 and the 8-bit D / A converter 72 with a relatively fine resolution. As described above, depending on the output of the A / D converter 5, the 8-bit D / A converters 71 and 8bi are provided.
The offset component of the vibration gyro is removed by finely and efficiently controlling (changing) the output of the t D / A converter 72.

Thereafter, a high pass filter (HPF) 8,
It is converted into an angular displacement signal via the integrator 9. Then, the outputs of the correction lens position sensor 10 for detecting the position of the correction lens (via the amplifier 11 and the A / D converter 12) are added in reverse polarity and feedback calculation is performed, and the signal is passed through the PWM converter 13. It is outputted as PWM from the output port of the lens microcomputer 4, and the correction lens is driven by the coil driver 14 to cancel the image blur.

[0012]

Now, consider an offset removing operation when the output from the vibration gyro 1 which is an angular velocity sensor for detecting shake is not normal.

1) When the gyro output signal is not supplied for some reason (disconnection, etc.) In this case, the 8-bit D / A converter 71 and the 8-bit D / A converter
Since only the output from the converter 72 is input to the non-inverting terminal of the operational amplifier 2, the inverting terminal output and the output of the amplifier 3 also output a voltage substantially the same as the non-inverting terminal output, and the manner of voltage change is also different. It will be similar. Since the output signal itself is not saturated, the data selecting / controlling unit 63 operates, but the amplifying unit 3 loses a normal amplifying function, so that even if the data selecting / controlling unit 63 operates, the output is a desired voltage. It does not become the change amount, but becomes a minute voltage change amount. Therefore, the target value is not reached in one operation of the data selection / control unit 63. By repeating this operation, the offset component is gradually removed.

However, the inconvenience that the control in the data selection / control unit 63 requires a considerable amount of time, and even if the output is output in the vicinity of the target value, the gyro output signal itself is not supplied. The image blur correction operation is not performed at all, which causes a problem. Even if the image stabilization operation is performed in such a state, the image stabilization effect on the viewfinder cannot be confirmed, or if you actually shoot it, a picture with no image stabilization effect will be taken. The person may feel distrust of the anti-vibration effect.

Further, even if it is considered that the equipment is out of order and the repair is performed thereafter, there is a disadvantage that the repair efficiency is deteriorated because the true cause is not specified at that time.

2) When the gyro signal is supplied, but the signal level is abnormal output level (when the offset voltage is abnormally large or the sensor output is H (high) level or L (low) level) In the case where the sensitivity is output to 0 in the vicinity, etc.) In this case, the offset removal operation is performed in the normal operation sequence as described above. However, since the offset voltage (null voltage) is large, the output saturation avoidance control unit 61 operates more than usual during the offset removal operation. Therefore, if the calculation time is correspondingly increased or the offset amount is too large, the correction voltage output becomes closer to saturation, and there is a possibility that the saturation of the sensor amplification output cannot be avoided.

Further, when a sensor having a large offset voltage is used, it is considered that the performance of the sensor itself is inferior, which may cause the desired vibration isolation performance to not be exhibited.

In the conventional example of FIG. 8, the above 1),
There is a problem that inconvenience such as 2) occurs.

(Object of the Invention) An object of the present invention is to make it possible to detect an abnormality in the vibration detecting means and its output, and when an abnormality is detected, perform an appropriate image blur correction operation based on the detection result. The present invention is intended to provide an image blur correction device capable of performing the above.

[0020]

To achieve the above object, the present invention provides a vibration detecting means for detecting vibration, a correction voltage output means for outputting a correction voltage, an output of the vibration detecting means and the correction. Comparing means for comparing the difference in voltage output,
In an image blur correction device having an offset removing unit that removes an offset component of the output of the vibration detecting unit by changing the correction voltage output based on the output of the comparing unit, an offset in the offset removing unit The image blur correction apparatus includes an offset removal abnormality determination unit that determines whether the removal operation is normal, and a control unit that controls the image blur correction operation based on the determination result of the offset removal abnormality determination unit.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will now be described in detail based on the illustrated embodiments. In the present embodiment, the case where the image blur correction device is mounted in the interchangeable lens of the single-lens reflex camera will be described.

FIG. 1 is a block diagram showing a circuit configuration of a single-lens reflex camera according to an embodiment of the present invention. In FIG. 1, reference numeral 101 is a lens microcomputer, and a contact 109c for communication (clock Signal), 109d
Communication is received from (main body → lens signal transmission), and a shake correction system 102, a focus drive system 104, and an aperture drive system 1 having the configuration shown in FIG.
The operation of 05 is performed. The shake correction system 102 includes a shake sensor 106 for detecting shake, a position sensor 107 for detecting a correction lens displacement, and a control signal calculated by the lens microcomputer 101 based on the outputs of the shake sensor 106 and the position sensor 107. A shake correction drive system 108 that drives a correction lens to perform a shake correction operation by means of. Also, 1
Reference numeral 24 (SWIS) is an anti-vibration switch for selecting the shake correction operation. When selecting the shake correction operation, the anti-vibration switch 124 is turned on.

The focus drive system 104 drives a lens for focus adjustment according to a command value from the lens microcomputer 101 to perform focusing. The diaphragm drive system 1
05 is a command value from the lens microcomputer 101,
The operation of squeezing the diaphragm to the set position or returning to the open state is performed. The lens microcomputer 101 is in a state inside the lens (focus position, aperture value state, etc.)
Also, information about the lens (open aperture value, focal length, data required for distance measurement calculation, etc.) is transmitted to the main body side through the communication contact 109e (lens → main body signal transmission).

The lens microcomputer 101, the shake correction system 102, the focus drive system 104, and the aperture drive system 105 constitute the lens electrical system 110.

Electric power is supplied to the lens electric system 110 from the in-camera power source 118 through the power contact 109a and the ground contact 109b.

Inside the camera main body, an electric system 111 inside the camera main body is provided as a distance measuring unit 112, a photometric unit 113, a shutter unit 114, a display unit 115, other control unit 116, and the start and stop of these operations. A camera microcomputer 117 for performing management, exposure calculation, distance measurement calculation, etc. is built in. Power is supplied to the in-camera electric system 111 from the in-camera power supply 118.

Further, 121 (SW1) is a switch for starting photometry and distance measurement, 122 (SW2) is a switch for starting a release operation, and these are generally two-step stroke switches. So, the switch SW1 turns on with the first stroke of the release button, and the second
The switch SW2 is turned on by a stroke. Reference numeral 123 (SWM) is an exposure mode selection switch, and the exposure mode can be changed by turning the switch ON or OFF.
Alternatively, the switch 123 and other operating members may be operated simultaneously.

FIG. 2 is a block diagram showing a specific circuit configuration of the lens microcomputer 101 and the shake correction system 102 of the lens electric system 110.

As the configuration, an offset removal abnormality determination circuit 508 for performing offset removal abnormality determination and a control circuit 509 for controlling the image blur correction operation based on the determination result of the offset removal abnormality determination circuit 508 are newly provided. Has the same configuration as that of the block diagram of FIG. 8 (the reference numeral is different from that of FIG. 8), and detailed description thereof will be omitted.

FIG. 3 is a flow chart showing a specific processing operation in the lens microcomputer 504 of FIG.

Here, the image blur correction operation is performed by an interrupt process that occurs at regular intervals. Then, the control in the first direction, for example, the pitch direction (vertical direction) and the control in the second direction, for example, the yaw direction (horizontal direction) are alternately performed. When an interrupt occurs, the lens microcomputer 504 starts the operation from step # 101 in the flowchart shown in FIG.

First, in step # 101, it is determined whether the control direction this time is the pitch direction or the yaw direction. If it is the pitch direction, the process proceeds to step # 102 to display various flags, coefficients, calculation results and the like. Set the data address so that it can be read and written as pitch data, and step # 1
Go to 04. On the other hand, in the yaw direction, step # 101
To step # 103, a data address is set so that various flags, coefficients, calculation results, etc. can be read and written as yaw data, and the process proceeds to step # 104.

In step # 104, the output of the vibration gyro 501, which is an angular velocity sensor, is A / D converted, and the result is stored in AD_DATA defined in advance in the RAM. Then, in the next step # 105, it is determined whether or not the image blur correction start is permitted. For example, the image blur correction start permission is given by ANDing the switch SWIS ON and the switch SW1 ON. If the start is permitted, the process proceeds to step # 106, and if not permitted, the process proceeds to step # 116.

Here, the start of image blur correction is permitted, and the process proceeds to step # 106. At the same time,
Vibration gyro 501, amplifier 503 and 8bit D / A
A power supply operation is performed on the converter 5071 and the 8-bit D / A converter 5072 (not shown).

At step # 106, the offset removal calculation end flag is determined. If the offset removal calculation is completed, it is H (high) level, and if it is not completed, it is L (low) level. Therefore, if the offset removal calculation completion flag is L level, the process proceeds to step # 107, and the vibration gyro Offset removal calculation to keep the amplified output within the dynamic range (avoid saturation) and output to a predetermined target value, and abnormality determination to determine whether the offset removal operation is properly performed and there is no abnormality To do. Until all of these calculations are completed, for example, the correction lens (not shown) is kept in the energized state. After that, the process proceeds to step # 116. The detailed operation here will be described separately based on the flowchart of FIG.

The offset removal calculation end flag is set to H.
If it is at the level, the offset removal calculation has been completed, so the routine proceeds to step # 108, where it is determined whether or not the image stabilization operation can be started based on the vibration gyro amplification output.
As a determination method, for example, it is determined whether the vibration gyro amplification output after the offset removal calculation in step # 107 is within a predetermined range within a predetermined time, that is, whether there is a large shake such as panning. To do.
If a large shake is included, an error may occur in the offset removal calculation in step # 107, and the vibration gyro amplification output may be saturated again when the large shake input is completed. As a result of the above determination, if it is not within the predetermined range within the predetermined time, the process proceeds to step # 109, and the offset removal calculation end flag is set to L in order to execute the offset removal calculation again. Then, it progresses to step # 116.

On the other hand, if it is within the predetermined range within the predetermined time,
When it is determined that the image stabilization operation can be started, the process proceeds from step # 108 to step # 110.
A high pass filter (HPF) calculation is performed. Then, in the next step # 111, integral calculation for image stabilization control is performed and converted into an image shake angular displacement signal (BURE_DATA). In the following step # 112, the output of the correction lens position sensor 512 that detects the position of the correction lens is fetched, and the A / D
Convert (after conversion = PSD_DATA). Then, in the next step # 113, feedback calculation {(BURE_DATA) −
(PSD_DATA)}. In the following step # 114, a phase compensation calculation is performed to make a stable control system, and in the next step # 115, PWM output is performed to the coil driver 516. As a result, image stabilization control is performed and image shake is corrected.

If the start of image blur correction is not permitted in step # 105,
After the operations of # 7 and # 109 are completed, the process proceeds to step # 116 as described above.

In step # 116, the initialization operation of the high pass filter (HPF) calculation and the integral calculation is performed. In this step, the image blur correction operation is not performed.

Image blur correction control is performed by the above steps # 101 to # 116.

Next, the offset removal calculation and the abnormality determination in step # 107 of FIG. 3 described above will be described with reference to the flowchart of FIG.

First, in step # 201, it is determined whether or not the setting for outputting the initial output from the D / A converter 507 is made. This is determined by, for example, the H level or L level of the flag. If it is set, the process immediately proceeds to step # 203, but if it is not set and is not output, the process proceeds to step # 202, and the D / A converters 5071 and D71 are used to output the initial output from the D / A conversion unit 507.
A digital initial value is set in the / A converter 5072.
Here, as a method of setting the initial value, for example, the TYP value of the reference voltage of the sensor is used as described above. Here, for example, the TY is connected to the non-inverting input terminal of the operational amplifier 502.
TYP to the D / A converter 5071 so that the P value is output.
(V) is set, and 0V is set in the D / A converter 5072. After that, the process proceeds to step # 203.

In step # 203, it is determined whether the A / D value of the vibration gyro amplification output is within the dynamic range. If the A / D reference voltage of the A / D converter 505 is AVref (V), for example, A / D
It is determined whether or not the D value is "AVref -0.1 V (= HI level)" or more. If it is above the HI level, the output is close to saturation or is likely to be saturated, so proceed to step # 204, and if it is below the HI level, step # 204.
Go to 205.

When the process proceeds to step # 204, the A / D value is not within the dynamic range and is likely to be saturated on the HI level side. Therefore, the D / value connected to the non-inverting input terminal of the operational amplifier 502 is high. The output of the A converter 507 is changed to control the output so that the A / D value is not saturated. As the variable amount of the output after amplification, the D / A conversion unit 507 is used once.
It is preferable that the amount of change is set so as not to exceed the reference voltage amount (AVref) for A / D conversion in the operation of. This is because the first purpose is to output the saturated output to an arbitrary level that does not saturate, so that the number of voltage changes is as small as possible.

Here, the amplification factor (R23 /
(Determined by R21) is A1, the operational amplifier 50
When the non-inverting input terminal of No. 2 is changed by ΔVref, the amplification output changes by (amplification factor A1 + 1 of the amplification section 503) × ΔVref. Y (LSB) is calculated as the amount of change in the digital set value of the A / D converter that does not exceed. From this, the "current digital set value-YLSB" of the D / A converter 5071 is set. On the other hand, the other D / A converter 5072 does nothing and remains as it is. As a result, the amplified output is reduced by {(A1 + 1) × ΔVref}. After this, the process proceeds to step # 207.

When step # 205 is reached, the A / D
It is determined whether or not the value is, for example, 0.1 V (= LO level) or more. If it is equal to or higher than the LO level, the output is not saturated and is within the dynamic range.
Go to. On the other hand, if it is less than the LO level, there is a high possibility that it is saturated, so the routine proceeds to step # 206.

When the operation proceeds to step # 206, the A / D value is not within the dynamic range and is likely to be saturated on the LO level side. The output of the D / A converter 507 connected to the input terminal is changed to control the output so that the A / D value is not saturated. Here, D / A
Only the converter 5071 displays "current digital set value + YL
SB ”is set. On the other hand, the other D / A converter 5072
Is left as is without doing anything. As a result, the amplified output is
Increase by {(A1 + 1) × Δvref}.

That is, saturation of the amplified output is avoided by performing Step # 204 or Step # 206 a plurality of times (the processing of Steps # 203 to # 206 is performed by the output saturation avoidance control unit 5061). That is, only the D / A converter 5071 is changed, and rough adjustment is performed so that the amplified output falls within the dynamic range.

Step # 204 or Step # 20
After the operation of step 6 is completed, the process proceeds to step # 207, and the counter 1 is counted up to count the number of operations of step # 204 or step # 206. Then, in the next step # 208, it is determined whether the value of the counter 1 is a predetermined value or more. If it is above the specified value,
Even if the operation of step # 204 or step # 206 is performed a predetermined number of times, the output saturation cannot be avoided, and some abnormal state is considered. Here, the predetermined value is set as, for example, the maximum value of the number of operations expected when using the normal sensor. If it is equal to or larger than the predetermined value, step # 2
If it is less than the predetermined value, the offset removal calculation &
The abnormality determination operation ends.

When the process proceeds to step # 209, the offset removal abnormality is detected, so the offset removal abnormality determination 1 flag is set to H. Then, in the next step # 210, since an abnormality is detected, the image blur correction start permission flag = L is set to immediately stop the image blur correction operation. In this embodiment, when the abnormality is detected, the image blur correction operation is immediately stopped. However, the image blur correction operation after that is prohibited at all, or the user is warned of the abnormal state (sound or display ) May be performed. After that, the offset removal calculation & abnormality determination operation ends.

Further, when proceeding from step # 205 to step # 211, since the A / D value is equal to or higher than the LO level and lower than the HI level, the vibrating gyro amplification output exists within the dynamic range where it does not saturate at this point. . Then, if this output is near the target value, for example, "AVref
/2±0.1V ”is determined. Here, the target value is set within ± 0.1 V, but it may be set in a narrower range or a wider range. If it is within the above range, the process proceeds to step # 219, and since it is near the target value, the offset removal calculation & abnormality determination operation of the shake sensor is completed. Then, the offset removal calculation end flag = H is set.

On the other hand, if it is outside the above range, step # 21.
2, the output is not saturated, but the deviation from the target value is large, so the D / A conversion unit 5 outputs the target value.
The output of 07 is controlled. First, for example, the target voltage value AVre
The deviation amount X X = (target voltage value-A / D value) of the current A / D value from f / 2 (V) is calculated. Then, in the next step # 213, D for outputting the target value corresponding to the value of X in advance is set.
From the data table (corresponding to the control data storage unit 5062) storing the digital data of the output change amount of the A / A converter 5071 and the D / A converter 5072, the above X
Control digital data (D / A converter 5
Control data of 071: ± αLSB, D / A converter 50
72 control data: ± βLSB) is read. In the following step # 214, both control data (± αLS
The output of the D / A converter 5071 and the D / A converter 5072 is changed based on B, ± βLSB).

That is, in steps # 212 to # 214, the amplified output within the dynamic range is output to or near the target value (steps # 212 to # 212).
The portion performing the operation of # 214 is the data selection / control unit 506.
3).

The control resolution is summarized as follows: 8-bit D
The output resolution of the A / A converter alone is low.
By controlling each 8bit D / A converter independently,
It is possible to control with high resolution. In the present embodiment, the amplification output resolution is {resistor R24 / (resistor R24 + resistor R25)} × (A when the output resolution of the 8-bit D / A converter alone is (A2) V / LSB.
2) V / LSB × (amplification factor of the amplification unit 503 + 1) is given, so that the minimum resolution can be freely set by setting the resistance ratio of the resistors R24 and R25.

In the next step # 215, the counter 2 is used to count the number of operations in step # 214.
To count up. Then, the next step # 216
At, it is determined whether the value of the counter 2 is a predetermined value or more. If the output exceeds the predetermined value, the output is not saturated, but even if the operation of step # 214 is performed a predetermined number of times, the output does not reach the vicinity of the target value, and some abnormal state is considered. Here, the predetermined value is set as, for example, the maximum value of the number of operations expected when using the normal sensor. If it is equal to or larger than the predetermined value, the process proceeds to step # 217,
If it is less than the predetermined value, the offset removal calculation & abnormality determination operation ends.

When the process proceeds to step # 217, an offset removal abnormality is detected, so the offset removal abnormality determination 2 flag is set to H. Then, in the next step # 218, since an abnormality is detected, the image blur correction start permission flag = L is set to immediately stop the image blur correction operation. In this embodiment, when the abnormality is detected, the image blur correction operation is immediately stopped. However, the image blur correction operation after that is prohibited at all, or the user is warned of the abnormal state (sound or display ) May be performed. After that, the offset removal calculation & abnormality determination operation ends.

By the above steps # 201 to # 219, the offset component superimposed on the amplified output signal of the shake sensor is removed, the output is output near the target value, and whether the offset removing operation is normal or not. Therefore, it is possible to immediately stop the image blur correction operation based on the determination result.

The above steps # 207 to # 209,
The part for performing the operations of # 215 to # 217 is the offset removal abnormality determination circuit 508, and steps # 210 and # 21.
The control circuit 509 is the part that performs the operation of No. 8.

According to the above-mentioned configuration, the offset removal abnormal operation can be detected in the offset component removal calculation superimposed on the amplified output signal of the vibration gyro, that is, the vibration gyro and its output abnormality can be detected. An appropriate image blur correction operation can be performed based on the result.

(Second Embodiment) Next, the operation of the main part of the image shake correction apparatus according to the second embodiment of the present invention will be described with reference to the flowchart of FIG.

In the second embodiment, in the operation of avoiding the output saturation at the initial stage, the D / A conversion unit 507 outputs D
Instead of counting the number of times the setting value of the A / A converter output is changed, it is determined whether or not the digital setting value corresponding to the output of the D / A converter is within a predetermined range. There is an advantage that it is not necessary to provide the counting means in the first embodiment.

In FIG. 5, the difference from the first embodiment is that step # 207 of the flowchart of FIG.
It is that points # 208 to # 208 are changed to step # 301.

Hereinafter, only changed portions will be described based on the flowchart of FIG. 5, and description of other similar portions will be omitted.

In step # 301, the above step # 2 is executed.
04 or it is determined whether the digital set value of the D / A converter 5071 after the operation of step # 206 is within a predetermined range. Here, the predetermined range is a D / A converter digital set value range that can be considered when a normal sensor is used, or a range from a settable maximum value to a settable minimum value. If it is outside the predetermined range, the output saturation cannot be avoided even if the D / A converter output is changed significantly, and some abnormal state is considered, and the process proceeds to step # 209 described above. If it is within the predetermined range, the offset removal calculation & abnormality determination operation is ended.

As described above, the offset component superimposed on the amplified output signal of the shake sensor is removed, the output is output near the target value, and it is determined whether or not the offset removal operation is abnormal. Based on the result, it becomes possible to immediately stop the image blur correction operation.

In the second embodiment, the offset removal abnormality determination circuit 508 performs the operations of steps # 301, # 209 and steps # 215 to # 217 of FIG. 5, and the operations of steps # 210, # 218. The control circuit 509 operates.

According to the above configuration, a simpler configuration is possible in the offset component removal arithmetic operation superimposed on the amplified output signal of the shake sensor (because the counting means is unnecessary).
Thus, the offset removal abnormal operation can be detected, and an appropriate image blur correction operation can be performed based on the detection result.

(Third Embodiment) Next, an image blur correction device according to a third embodiment of the present invention will be described.

The third embodiment is the same as the first embodiment.
# 209 and step # 2 of FIG.
By writing the abnormality detection result of No. 17 in the nonvolatile storage means, the cause of the abnormality can be easily identified even when the power is turned off thereafter.

FIG. 6 is a block diagram showing a specific circuit configuration of a lens microcomputer and a shake correction system as a lens electric system according to the third embodiment of the present invention. As shown in Figure 2,
A nonvolatile storage means 517 is added to the lens electric system block diagram in the second exemplary embodiment of the present invention, and detailed description of other configurations will be omitted.

FIG. 7 is a flow chart showing the operation of the main part in the third embodiment of the present invention. The difference from the first embodiment is the steps # 209 and # 210 in the flow chart of FIG. Between step # 401, and the point that step # 401 is inserted
The point is that step # 402 is inserted between 217 and step # 218.

Below, only the changed parts will be explained based on the flowchart of FIG. 7, and the explanation of other similar parts will be omitted.

In step # 401, the above step # 2 is executed.
09 abnormality detection result is stored in the non-volatile storage means 517.
Write in.

In step # 402, the abnormality detection result in step # 217 is written in the non-volatile storage means 517.

As described above, the offset component superimposed on the amplified output signal of the shake sensor is removed, the output is output near the target value, and it is judged whether or not the offset removing operation is abnormal, and the abnormality is detected. If there is, it is possible to write the determination result in the non-volatile storage means 517 and immediately stop the image blur correction operation based on the determination result.

In the third embodiment, steps # 208 to 210, # 401, # 215 to # 217 of FIG.
The part that performs the operation of # 402 is the offset removal abnormality determination circuit 508, and the part that performs steps # 210 and # 218 is the control circuit 509.

According to the above configuration, the offset removal abnormal operation can be detected in the offset component removal calculation superimposed on the amplified output signal of the shake sensor, that is, the vibration gyro and its output abnormality can be detected. It is possible to perform an appropriate image blur correction operation based on the result, and since the result of the abnormality detection is held even when the power is turned off thereafter, it is possible to easily identify the cause of the abnormality.

(Modification) In each of the above embodiments, an example in which the present invention is applied to a single-lens reflex camera has been described, but the present invention is not limited to this, and can be applied to an interchangeable lens or a video movie. .

Further, although an example in which an angular velocity sensor (vibration gyro) is used as the vibration detecting means is shown, an angular acceleration sensor, an acceleration sensor, a speed sensor, an angular displacement sensor,
Any means such as a displacement sensor can be used as long as it can detect shake.

Further, as the correction means including the correction lens, a shift optical system for moving an optical member in a plane perpendicular to the optical axis, a light flux changing means such as a variable apex angle, and a photographing screen in a plane perpendicular to the optical axis. Any device that can correct the image blur such as a moving device may be used.

Further, the structure of the invention or each embodiment described in each claim is such that it forms one device as a whole, or is separated or combined with another device. It may be, or may be like an element constituting the device.

[0082]

As described above, according to the present invention,
It is possible to provide an image blur correction device capable of detecting an abnormality in the vibration detection means and its output and capable of performing an appropriate image blur correction operation based on the detection result when an abnormality is detected.

[Brief description of drawings]

FIG. 1 is a block diagram showing an electrical configuration of a single-lens reflex camera according to each embodiment of the present invention.

FIG. 2 is a block diagram showing a specific circuit configuration in the interchangeable lens according to the first embodiment of the present invention.

FIG. 3 is a flowchart showing an image blur correction interrupt control operation in the first embodiment of the invention.

FIG. 4 is a flowchart showing details of offset removal calculation and abnormality determination in the first embodiment of the present invention.

FIG. 5 is a flowchart showing details of offset removal calculation and abnormality determination in the second embodiment of the present invention.

FIG. 6 is a block diagram showing a specific circuit configuration in an interchangeable lens according to a third embodiment of the present invention.

FIG. 7 is a flowchart showing details of offset removal calculation and abnormality determination according to the third embodiment of the present invention.

FIG. 8 is a block diagram showing a specific circuit configuration in a conventional interchangeable lens.

[Explanation of symbols]

101 lens microcomputer 102 Shake correction system 104 Focus drive system 102 Aperture drive system 106 shake sensor 107 Position sensor 108 Shake correction drive 110 lens electrical system 111 In-camera electrical system 112 Distance measuring unit 113 Light meter 114 shutter 115 display 116 Other control unit 117 camera microcomputer 115 In-camera power supply 124 SWIS 501 vibrating gyro 502 operational amplifier 503 Amplifier 504 lens microcomputer 505 A / D converter 506 Offset compensation circuit 5061 Output saturation avoidance unit 5062 Control data storage unit 5063 Data selection / control unit 507 D / A converter 5071 8bit D / A converter 5072 8bit D / A converter 508 Offset removal abnormality determination circuit 509 Control circuit 510 High-pass filter (HPF) 511 Integral calculation unit 512 correction lens position sensor 513 amplifier 514 A / D converter 515 PWM output section 516 coil driver 517 non-volatile storage

Claims (7)

[Claims] 1. A vibration detecting means for detecting vibration, a correction voltage outputting means for outputting a correction voltage, and a comparing means for comparing a difference between an output of the vibration detecting means and the correction voltage output.
An image blur correction apparatus comprising: an offset removing unit that removes an offset component of the output of the vibration detecting unit by changing the correction voltage output based on the output of the comparing unit. An image blur correction apparatus comprising: an offset removal abnormality determination unit that determines whether or not there is an abnormality in a removal operation; and a control unit that controls an image blur correction operation based on a determination result of the offset removal abnormality determination unit. 2. The image blur correction device according to claim 1, wherein the correction voltage output means is composed of one or a plurality of D / A converters. 3. The image blur correction apparatus according to claim 1, wherein the control unit stops the image blur correction operation when the offset removal abnormality detection unit determines that the image blur is abnormal. 4. The offset removal abnormality determining means has a counting means for counting the number of changes of the correction voltage output in the offset removing means, and when the count value of the counting means is a predetermined value or more, an offset removing operation is performed. The image blur correction device according to any one of claims 1 to 3, wherein the image blur correction device determines that is abnormal. 5. The output saturation avoidance control unit, wherein the offset removal unit changes the correction voltage output by a constant voltage change amount so that the output of the comparison unit becomes an arbitrary output value that does not saturate circuitally, A control data storage unit that stores the output of the arbitrary comparison unit that is not saturated in the circuit after the change by the output saturation avoidance control unit as correction voltage output control data for outputting to a target value; Data selection for selecting the appropriate correction voltage output control data from the control data storage unit according to the difference between the output of the comparison means and the target value, and changing the correction voltage output according to the correction voltage output control data. A first count for counting the number of changes of the correction voltage output in the output saturation avoidance control unit, wherein the offset removal abnormality determination unit includes a control unit. Second counting and stages, the number of changes of the correction voltage output in the data selection and control unit
And a count value of the first count means is equal to or larger than a first predetermined value or a count value of the second count means is equal to or larger than a second predetermined value, the offset removing operation is performed. Claim 2 or 3 which is determined to be abnormal
The image blur correction device described in 1. 6. The offset removal abnormality determination means determines that the offset removal operation is abnormal when a digital set value corresponding to the correction voltage output in the offset removal means falls outside a predetermined range. Alternatively, the image blur correction device according to item 3. 7. The non-volatile storage means for storing the result of the determination that the offset removal operation is determined to be abnormal by the offset removal abnormality determination means is stored. Image stabilization device.