JPH0980524A - Shake correcting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To execute appropriate shake correction control even when the potential of voltage falls. SOLUTION: This device is provided with a shake detection part detecting shake acting on two axes in a direction perpendicular to an optical axis direction, a shake correction mechanism part 53 changing the optical axis of a photographing optical system in the directions of two axes, a driving part 52 driving the mechanism part 53, a voltage detection part detecting the power supply voltage value of the driving part 52, and control parts 3, 12 and 17 controlling the driving part 52, based on output from the shake detection part. The control parts 3, 12 and 17 control the driving of the mechanism part 53 in accordance with an output value from the voltage detection part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blur correction device for correcting image blur caused by camera shake in a camera or the like.

[0002]

2. Description of the Related Art Conventionally, an optical axis of a photographic optical system is detected by detecting a blur caused in a camera, a video, etc. by an angular velocity sensor and moving the photographic optical system in a direction opposite to the detected blur direction. There is known a blur correction device that corrects image blur by changing the image blur (Japanese Patent Application Laid-Open No. 2-183217).
No.). FIG. 8 is a block diagram showing an example of a blur correction device applied to a conventional camera device with interchangeable lenses. The camera device is a camera body 5 electrically connected.
4 and a taking lens 55. In the camera body 54, a (DC / DC) converter 2, a CPU 3
Etc. are provided. On the other hand, in the taking lens 55,
(DC / DC) converter 16, CPU12, CPU1
7 etc. are provided.

The battery 1 is mounted in the camera body 54 and supplies power to the camera body 54 and the taking lens 55. The camera body 54 and the taking lens 55 are electrically connected by electrical contacts 6, 7, 8, 9, and 10. The electric contact 6 is provided from the battery 1 via the power supply control switch 4 which is a semiconductor switch to the photographing lens 55.
Is a contact for supplying power to. The electrical contact 7 is a contact for supplying the output of the converter 2 to the taking lens 55. The electrical contacts 8 are a group of contacts for performing communication between the CPU 3 and the master CPU 12. The electrical contact 9 is a GND (ground) line connected to the cathode terminal of the battery 1. The electrical contact 10 is a GND line that is grounded to the metal object of the camera body 54.

The CPU 3 mainly controls the inside of the camera body 54. When a start switch (not shown) is operated, the CPU 3 controls the converter 2 and, via the electrical contact 7, the master CPU 12 and the EEPROM.
Power is supplied to 13 (electrically rewritable nonvolatile memory). Further, the master CPU 12 outputs a power supply request signal for the electric contact 6 to the CPU 3 via the electric contact 8. C
The PU 3 supplies power from the battery 1 from the power supply control switch 4 to the converter 16 via the electrical contact 6.

When power is supplied from the electrical contact 7, the master C
The PU 12 activates the converter 16. Converter 1
6 is a constant voltage regulator 18, a slave CPU 17,
Power is supplied to the control circuits of the motor drivers 20 and 23. The constant voltage regulator circuit 18 supplies power to the shake detection circuit and the analog processing circuit 19. In the case of the analog processing circuit 19, since the dynamic range of the signal component is widened, the power source of the processing circuit must also have a low noise level. Here, if the output of the converter 16 is directly used,
Due to the characteristic that this power supply is a switching power supply, the noise level is not sufficiently low. Therefore, power is supplied to the circuit that performs analog processing via the constant voltage regulator circuit 18.

The blur amount detected by the analog processing circuit 19 is analog-processed and input to the master CPU 12. When either the start switch 5 (camera body 54 side) or the start switch 14 (photographing lens 55 side) is turned on, the master CPU 12 calculates the amount to drive the motors 21 and 24 based on this data, It is transmitted to the slave CPU 17. Slave CPU1
7 outputs the amount to be driven to the motor drivers 20 and 23, and drives the motors 21 and 24.

The motors 21 and 24 convert a rotational movement into a linear movement by a gear or the like (not shown) and drive a correction optical system (not shown). Position detection circuits 22 and 25
Detects the position of the correction optical system due to the rotation of the motors 21 and 24. The position detection circuits 22 and 25 know the deviation from the control amount by the feedback pulse from the photo interrupter element or the like, for example. The master CPU 12
The voltage of the electrical contact 6 is monitored (reference numeral 15). When this voltage value is below a predetermined value, a warning is issued or control is stopped. The resistor 11 is used for the motors 21 and 2
When 4 rotates and a large current flows into the electrical contact 9,
It has a low resistance provided so that the potential difference from the electrical contact 10 does not become large.

FIG. 9 is a flow chart showing an example of control of the blur correction device of FIG. First, in step A2, when the correction start trigger is turned on while waiting for the trigger signal for starting the image blur correction control, the process proceeds to step A3, where the battery check is performed, and the output voltage of the battery 1 and a predetermined reference value (reference) are set. To compare. If the output voltage of the battery 1 is smaller than the reference value, the process waits until it becomes larger. If the output voltage of the battery 1 is larger than the reference value, the process proceeds to step A4.

At step A4, the CPU 3 causes the master C
A command for image blur correction control (both axes) is transmitted to the PU 12. As a result, the slave CPU 17
First, in step A5, the subroutine "X-axis signal processing (steps B1 to B9)" is called, and in the next step A6, the X-axis output signal is fetched and the driving amount of the image blur correction mechanism unit is calculated. Then, in step A7, the X-axis correction mechanism unit is driven based on the calculation result.

Then, in step A8, the subroutine "Y-axis signal processing (steps C1 to C9)" is called, and in the next step A9, the output signal of the Y-axis is fetched and the drive amount of the image blur correction mechanism section is calculated. To do. Then, in step A10, the Y-axis correction mechanism unit is driven based on the calculation result. Next, in steps A11 and A12, the drive amount of each axis is monitored, and in step A13, it is determined whether or not the correction start trigger signal is held in the ON state. If not held, the process proceeds to step A14 to end the processing, and if held, the process returns to step A5.

Now, the X-axis and Y-axis signal processing of the subroutine will be described. In steps B2 and C2, the same signal from the blur detection sensor is detected. Then, in steps B3 and C3, only necessary signal frequency components are selected (filtered) and amplified in the following steps B4 and C4.
Then, this signal is subjected to A / D conversion in steps B5 and C5, and further subjected to averaging processing in steps B6 and C6. Then, sensor output reference value calculation processing (ω0 detection) is performed in steps B7 and C7, and the subroutine returns in steps B9 and C9.

[0012]

However, the above-mentioned conventional blur correction device has the following problems. The drive source (actuator) for blur correction uses a correction optical system on the X-axis,
Two are required to drive the Y-wheel drive. When these are incorporated into a camera system, the battery 1 serving as a power source supplies power to both a large power consumption circuit that drives an actuator and the like and a small power consumption circuit that controls the actuator and the like. The small power consumption circuit does not operate normally unless a stable power supply voltage is supplied, as represented by a microcomputer. Therefore, the power supply voltage from the battery 1 is supplied to the small power consumption circuit via the voltage stabilizing circuit (for example, DC / DC converter or the like). On the other hand, the voltage of the large power consumption circuit is preferably stable and is preferably small in output resistance of the voltage source in order to extract a large current. Therefore, the large power consumption circuit is directly supplied with power from the terminal of the battery 1.

However, since there is an output resistance component also at the terminal of the battery 1, when a current is taken out from the battery 1, a potential drop of the terminal voltage proportional to the current value occurs. If the terminal voltage drops too much, the output voltage of the converter feeding the small power consumption circuit cannot maintain a stable state. In particular, when the actuators for two axes (a plurality of) are required as in the case of blur correction, such a potential drop is likely to occur.

An object of the present invention is to perform appropriate shake correction control even when a voltage drop occurs.

[0015]

In order to solve the above-mentioned problems, the invention according to claim 1 is a shake detecting section for detecting shake acting on two axes perpendicular to the optical axis direction, and the two axes. A shake correction mechanism that changes the optical axis of the shooting optical system in the direction of,
A blur correction device including a drive unit that drives the blur correction mechanism unit, a voltage detection unit that detects a power supply voltage value of the drive unit, and a control unit that controls the drive unit based on an output of the blur detection unit. The control unit controls driving of the shake correction mechanism unit according to an output value of the voltage detection unit.

According to a second aspect of the present invention, there is provided a blur detection unit for detecting blur acting on two axes perpendicular to the optical axis direction, and
A shake correction mechanism unit that changes the optical axis of the photographing optical system in the axial direction, a drive unit that drives the shake correction mechanism unit, a voltage detection unit that detects a power supply voltage value of the drive unit, and the shake detection unit And a controller for controlling the drive unit based on the output of the controller, wherein the controller detects the shake when the power supply voltage value detected by the voltage detector is equal to or less than a predetermined value. When the difference between the first axis component and the second axis component is equal to or more than a predetermined amount, the first axis component and the second axis component of the blur detected by the part are compared with each other. It is characterized in that only the correction mechanism unit is driven.

According to a third aspect of the present invention, in the blur correction device according to the second aspect, the control unit is configured to: when the power supply voltage value detected by the voltage detection unit is equal to or less than a predetermined value,
The first axis component and the second axis component of the blur detected by the blur detection unit are compared, and when the difference between the first axis component and the second axis component is equal to or more than a predetermined amount, the axis having the large blur component is compared. The drive of the shake correction mechanism is controlled only when the power supply voltage value detected by the voltage detector is equal to or less than a predetermined value. It is characterized by doing.

[0018]

DETAILED DESCRIPTION OF THE INVENTION An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing an embodiment of a camera to which a blur correction device according to the present invention is applied. The block diagram of this camera is the same as that of the conventional example shown in FIG. In FIG. 1, the CPU 3 in the camera body 54 is a master C in the taking lens 55.
Communicate with the PU 12. The master CPU 12 issues a command to control the slave CPU 17, and
The autofocus drive unit 50 and the autofocus optical system 51 are controlled. Furthermore, the slave CPU 17
Controls the image blur correction drive unit 52 and the image blur correction optical system 53.

FIG. 2 is a diagram showing the configuration of the analog processing circuit 19. When the camera shakes, the shake detection sensor 26 detects the angular velocity due to the shake. The low-pass filter (LPF) 27 cuts off the detected signal from high frequencies. This signal is passed to the next high pass filter (HP
F) 28. The high-pass filter 28 cuts off low-frequency frequencies and then transmits them. This signal is
It is amplified to a predetermined size by 9. The amplified signal is A / D converted by the A / D converter 30, transmitted to the CPU 12 as digital data, and processed. If the CPU 12 has an A / D conversion function, that function may be used.

FIGS. 3 and 4 are diagrams for explaining how the blur correction apparatus according to the present invention captures a blur as a vector and how to control and compensate for the blur vector. In FIGS. 3 and 4, the biaxial directions are the X and Y axes, which are in the horizontal and vertical directions. In FIG. 3, arrows a, b, and c represent blurring as a vector with the origin being the starting point. Further, the concentric circles centering on the origins of the X axis and the Y axis are divided into three areas, area 2, and area 3, respectively. Here, the area 1 and the area 2 include the origin. That is, the region 1 and the region 2 have a substantially circular shape instead of the substantially donut shape.

Region 1 is a region in which the end of the shake vector a for which shake correction control is possible is present when the power supply voltage value is at or above a predetermined value. Region 2 is a region where a shake vector capable of shake correction is present when the power supply voltage value is the battery check first level. Therefore, the battery check first
At the time of level, when the end of the blur vector exists outside the area 2, the blur vector is corrected with the blur vector b existing in the area 2 as a limit.
Region 3 is a region where the shake vector capable of shake correction at the power supply voltage second level of the battery check exists.
Therefore, at the second level of the battery check, when the end of the blur vector is outside the area 3, the blur vector is corrected with the blur vector c existing in the area 3 as a limit.

In FIG. 4, a substantially cross-shaped region along the X and Y axes shows an example in which the magnitude of one axis component of the blur vector is significantly different from the magnitude of the other axis component. For example, when the end of the blur vector exists in the X-axis control region like the blur vector d, the blur correction control is performed on the blur vector d when the power supply voltage value is equal to or higher than a predetermined value. Further, at the first level of the battery check, the shake correction control is performed on the shake vector e existing in the region 2 of the X component of the shake vector. Furthermore, at the second level of the battery check, the shake correction control is performed on the shake vector f existing in the region 3 of the X component of the shake vector. That is, in the case where the blur vector exists in the X and Y axis control regions, when the battery check is at the first and second levels, the blur correction is performed only on the X and Y axis components, respectively.

FIG. 5 is a flow chart showing an embodiment of control of the blur correction device according to the present invention. First, in step D2, the process is in a state of waiting for a trigger signal for starting the image blur correction control. When the correction start trigger is turned on, the process proceeds to step D3, where a battery check is performed to compare the output voltage BC of the battery 1 with a predetermined reference value (reference).

When the output voltage of the battery 1 is higher than the reference value, the process proceeds to step D4, where the CPU 3 is the master CPU.
A command for performing image blur correction control (both axes) is issued to 12. As a result, the slave CPU 17 calls the subroutine "X-axis signal processing" in step D5, and in the next step D6, takes in the X-axis output signal at that time and calculates the drive amount of the image blur correction drive unit 52. . Then, in step D7, the X-axis image blur correction driving unit 52 is driven based on the calculation result.

Subsequently, the slave CPU 17 calls the subroutine "Y-axis signal processing" in step D8, and in the next step D9, the Y-axis output signal at that time is fetched and the driving amount of the image blur correction driving section 52 is fetched. Is calculated. And
In step D10, the Y-axis image blur correction driving unit 52 is driven based on the calculation result. In the next steps D11 and D12, pulses of the X-axis and Y-axis motors are detected to monitor the drive amount. Then, in step D13, it is determined whether or not the correction start trigger signal is kept ON. If not held, the process proceeds to step D14 to end the process, and if held, the process returns to step D5.

On the other hand, in step D3, when the output voltage BC of the battery 1 is smaller than the reference value, the process proceeds to step D15, the voltage value BC monitored by the battery check is divided by the predetermined value C1, and this value becomes α. Is set. And
In the next step D16, in order to perform arithmetic processing using the signal from the analog processing circuit 19, a “blur correction command”
Is issued. Then, in steps D17 and D20, the analog signal processing subroutine of each axis is called. In the next steps D18 and D21, the analog signal output obtained by this subroutine call is XS (X axis), Y
It is set to S (Y axis). Furthermore, steps D19 and D
In step 22, XS and YS are set to α set in step D15.
, And these values are set to XS and YS, respectively. Then, in step D23, XS / YS is calculated as a parameter to determine the difference between XS and YS, and this value is set to β.

In the next step D24, the magnitude of this β and the predetermined value β1 is compared, and when β> β1, that is, when the X-axis component is larger than the Y-axis component of the blur vector, the process proceeds to step D32. , X-axis drive only. Then, in step D33, the pulse of the X-axis motor is detected and the drive amount is monitored. Then, step D34
Then, it is determined whether or not the correction start trigger signal is kept ON. If it is not held, the process proceeds to step D35 to end the processing, and if it is held, the process returns to step D5. On the other hand, when β> β1 is not satisfied in step D24,
In step D25, the magnitude of β and the predetermined value β2 are compared, and when β <β2, that is, when the Y-axis component is larger than the X-axis component of the blur vector, the process proceeds to step D36 and only the Y-axis is calculated. Drive. Then, step D37
At, the pulse of the Y-axis motor is detected and the drive amount is monitored. Next, in step D38, the correction start trigger signal is O
It is determined whether or not N is held. If it is not held, the process proceeds to step D39 to end the processing, and if it is held, the process returns to step D5.

If β <β2 is not satisfied in step D25, it means that there is no significant difference in the magnitudes of the vectors of the X-axis component and the Y-axis component.
In step 6 and D27, both X and Y axes are driven. Then, in the next steps D28 and D29, the pulses of the X and Y axis motors are detected, respectively, and the drive amount is monitored.
Next, at step D30, it is judged if the correction start trigger signal is kept ON. If it is not held, the process proceeds to step D31 to end the process, and if it is held, the process returns to step D5. Note that β1 and β2 described above are values that satisfy at least the following conditions. β1> 1, 0 <β2 <1

By the way, the one-axis signal processing of the subroutine used for the above-mentioned X-axis signal processing and Y-axis signal processing (steps D5, D8, D17, D20) is step D40.
It is a process started from. First, when the one-axis signal processing is called in step D40, the signal of the shake detection sensor as it is is detected in step D41. Then, in step D42, only the necessary signal frequency components are selected,
The signal is amplified in step D43. Then, this signal is A / D converted in step D44,
At 45, an averaging process is performed. In the next steps D46 and D47, sensor output reference value calculation processing (ω0 detection) is performed, and in step D48, the subroutine returns.

FIG. 6 is a diagram showing an embodiment of the battery check circuit. When checking the battery, the CPU 12 first controls the port P1 and activates the converter 16. At that time, the output voltage is applied to the base of the NPN transistor 31 through the resistor 36. Then, the NPN transistor 31 is rendered conductive, and the collector current is drawn from the base of the PNP transistor 32 via the resistor 38. Then, the PNP transistor 32
Is conducted, the collector current flows into the voltage dividing resistors 33 and 34, and a voltage is generated at the connection point of the voltage dividing resistors 33 and 34. The generated voltage charges the capacitor 35, and finally the voltage of the battery 1 is changed to the PNP transistor 3
It is considered that the voltage between the collector and the emitter of 2 is subtracted, and a voltage obtained by dividing this voltage by the voltage dividing resistors 33 and 34 is applied. This voltage is the A / D of CPU12
It is possible to read at the conversion port port AN1 and use that value to perform a battery check.

FIG. 7 is a diagram showing an embodiment of the motor drive circuit. When the control circuit 40 receives the input signals 1 and 2, the control circuit 40 code-latches the signals IN1 and IN2, outputs the code from the output terminals CTL1, CTL2, CTL3, and CTL4, and drives the drive circuit composed of the MOS transistors on the right side in the figure. It controls the gates of transistors 41, 42, 43, and 44, respectively. Diodes 45, 46, 4
Since the motor 49 is an inductive load, the reference numerals 7 and 48 are so-called free-wheeling diodes that allow the energy stored by the magnetic flux to escape to the power supply line. For example, when the motor 49 is normally rotated, the transistors 41 and 4 are
4 is turned on and the transistors 42 and 43 are turned on.
Control to FF state. Similarly, when the motor 49 is rotated in the reverse direction, the transistors 41 and 44 are controlled in the OFF state, and the transistors 42 and 43 are controlled in the ON state.
When the brake state is set, the transistors 41 and 42 are controlled in the OFF state, and the transistors 43 and 4 are
4 is turned on. When brought into a stop state, the transistors 41, 42, 43, and 44 are controlled to be in an OFF state.

As described above, when the power supply voltage value is less than or equal to the predetermined value, the drive of the shake correction device is suppressed, and further,
Depending on the shake, the shake correction is performed only on one axis, so that the potential drop of the voltage can be prevented. Note that, in the above-described embodiment, an example in which the driving of the shake correcting apparatus is suppressed is shown, but the driving of the shake correcting apparatus may not be performed depending on the power supply voltage value.

[0033]

According to the first aspect of the present invention, even if a voltage drop occurs, proper shake correction control can be performed in accordance with the power supply voltage value. Claim 2,
According to the invention of 3, when a voltage drop occurs,
When the component of one of the two axis components of the shake is significantly larger than the component of the other axis, the shake correction is performed only for the axis with the larger component, so the voltage drop of the voltage When the occurs, it is possible to approximately appropriately perform the shake correction. As a result, the power consumption of the battery can be reduced, and it is possible to prevent a hang-up of the control unit, a system down, etc. due to a decrease in the power supply voltage value.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of a camera to which a blur correction device according to the present invention is applied.

FIG. 2 is a diagram showing a configuration of an analog processing circuit 19.

FIG. 3 is a diagram illustrating how a blur correction device according to the present invention captures a blur as a vector, and how to control and correct the blur vector.

FIG. 4 is a diagram illustrating how a blur correction device according to the present invention captures a blur as a vector, and how to control and correct the blur vector.

FIG. 5 is a flowchart showing an embodiment of control of the image stabilization apparatus according to the present invention.

FIG. 6 is a diagram showing an embodiment of a battery check circuit.

FIG. 7 is a diagram showing an embodiment of a motor drive circuit.

FIG. 8 is a block diagram showing an example of a shake correction device applied to a conventional camera device with interchangeable lenses.

9 is a flowchart showing an example of control of the shake correction device in FIG.

[Explanation of symbols]

 3 CPU 12 Master CPU 17 Slave CPU 50 Auto Focus Drive Unit 51 Auto Focus Optical System 52 Image Blur Correction Drive Unit 53 Image Blur Correction Optical System 54 Camera Body 55 Photographic Lens

Claims (3)

[Claims] 1. A shake detection unit that detects shake acting on two axes perpendicular to the optical axis direction, a shake correction mechanism unit that changes the optical axis of a photographing optical system in the directions of the two axes, and the shake correction unit. A shake correction device including a drive unit that drives a correction mechanism unit, a voltage detection unit that detects a power supply voltage value of the drive unit, and a control unit that controls the drive unit based on an output of the shake detection unit. The control unit controls driving of the blur correction mechanism unit according to an output value of the voltage detection unit. 2. A shake detection unit that detects shake acting on two axes perpendicular to the optical axis direction, a shake correction mechanism unit that changes the optical axis of the photographing optical system in the directions of the two axes, and the shake correction unit. A shake correction device including a drive unit that drives a correction mechanism unit, a voltage detection unit that detects a power supply voltage value of the drive unit, and a control unit that controls the drive unit based on an output of the shake detection unit. The control unit compares the first axis component and the second axis component of the blur detected by the blur detection unit when the power supply voltage value detected by the voltage detection unit is equal to or less than a predetermined value, and The blur correction device is characterized in that when the difference between the first axis component and the second axis component is equal to or more than a predetermined amount, only the blur correction mechanism section of the axis having a large blur component is driven. 3. The blur correction device according to claim 2, wherein when the power supply voltage value detected by the voltage detection unit is equal to or less than a predetermined value, the control unit controls the blurring detected by the blurring detection unit. When the difference between the first axis component and the second axis component is greater than or equal to a predetermined amount by comparing the 1st axis component and the 2nd axis component, only the drive of the shake correction mechanism section of the axis having a large shake component is performed. The shake correction apparatus controls the drive of the shake correction mechanism unit on an axis having a large shake component when the power supply voltage value detected by the voltage detection unit is equal to or less than a predetermined value.