JP2000350084A - Shake correction device for optical device, shake correction method and the optical equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the quality as a product by preventing grating sounds from being produced due to a correction use shift lens striking the end of a mirror barrel at the interruption of power in a shake correction device that corrects a shake of a video camera or the like. SOLUTION: An angular velocity sensor 101 senses the shake component of a device main body, an adder 113 receives a signal in response to the sensing information and a driver 114 receiving an output of the adder 113 drives a shake correction purpose shift lens 115. Furthermore, a position sensor 116 senses the shift position of the shift lens 115, a position sensor amplifier 117 amplifies a signal denoting the sensing result by the sensor 116 and feeds the amplified signal back to the adder 113, and a gain control circuit 120 changes the gain of the position sensor amplifier 117, on the basis of a result of monitoring on/off of a power switch 118.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shake correction apparatus, a shake correction method, and an optical apparatus for an optical device for correcting the influence of a shake such as a camera shake of a video camera.

[0002]

2. Description of the Related Art Conventionally, in the field of photographing equipment such as a camera and a video camera, automation and diversification of all points, such as exposure setting and focus adjustment, have been attempted, so that good photographing can be easily performed. Has become. In recent years, a shake correction device for correcting camera shake has been put to practical use. In particular, in a small-sized video camera, camera shake on the telephoto side becomes conspicuous due to an increase in the magnification of the lens, and the quality of an image is significantly reduced. Therefore, it is an essential requirement to provide a shake correction device as described above. ing.

The above-mentioned shake correcting apparatus includes at least shake detecting means for detecting a shake component, and shake correcting means for correcting the influence of the shake in accordance with the detection result of the detecting means. These include electronic detection methods that detect image movement by comparing images between consecutive fields or frames, and methods that directly measure camera movement using an angular velocity sensor or angular acceleration sensor. Can be On the other hand, as shake correction means,
In addition to optical correction means for optically adjusting the angle of the photographing optical axis in a direction in which camera shake is removed, a range (cutout range) for actually recording or outputting is electronically selected from the obtained images. So-called electronic correction means and the like can be mentioned.

FIG. 6 is a block diagram showing a configuration example of a device equipped with a lens having a shake correction function as described above.
Although the control is originally performed separately in the vertical and horizontal directions, only one of them is shown here because the configuration is exactly the same.

In FIG. 6, reference numeral 101 denotes each speed sensor, which is attached to a main body of a photographing device such as a video camera, and outputs an angular velocity signal corresponding to the shake when the shake occurs. 102 is a high-pass filter (hereinafter referred to as HPF), 103 is an angular velocity sensor amplifier for amplifying the angular velocity signal, and 104 is a low-pass filter (hereinafter referred to as LPF).
One output signal is subjected to predetermined frequency limitation and amplification, and a shake signal due to hand shake or the like is generated.

The shake signal is input to a microcomputer (hereinafter referred to as IS microcomputer) 111 for performing control relating to shake correction, and is input to an analog-digital (hereinafter A / D) microcomputer.
D), a target value for driving the shift lens 115 is calculated through the converter 105, the HPF 106, the phase compensation circuit 107, and the integrator 108. The signal of this target value is output as, for example, a pulse width modulation (PWM) signal as an output from the IS microcomputer 111. Then, the PWM signal is smoothed by the LPF 112 and converted into an analog signal.

Reference numeral 109 denotes an output fixing circuit for fixing a target value. Reference numeral 110 denotes a changeover switch for switching the output from the IS microcomputer 111 to the output of the integrator 108 or the output of the output fixing circuit 109. The output of the output fixing circuit 109 normally outputs a value that is optically central, and is selected when the shake correction is off.

On the other hand, the movement of the shift lens 115 is detected by a position sensor 116 such as a Hall element, and the detection signal is amplified by a position sensor amplifier 117 and negatively input to the adder 113 as a feedback signal. The adder 113 adds the above-described target value and the feedback signal, and calculates a control amount of the shift lens 115 here. The driver (drive circuit) 114 drives the voice coil motor in the shift lens 115 according to the control amount.

By performing the above operation both in the vertical and horizontal directions, the camera shake of the device is corrected.

[0010]

However, in the above-described conventional shake correction apparatus, the power is particularly turned off because the shift lens is normally located near the center of the optical axis by the voice coil motor during normal operation. Sometimes, the shift lens drops due to its own weight and hits the lens barrel, producing an unpleasant sound, resulting in poor quality.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and can prevent a shift lens from hitting a lens barrel when a power switch or the like is turned off, thereby generating a harsh sound. It is an object of the present invention to provide a shake correction device, a shake correction method, and an optical device for an optical device that can improve the quality of the optical device.

[0012]

According to the present invention, a shake correcting apparatus, a shake correcting method, and an optical apparatus for an optical apparatus according to the present invention are configured as follows.

(1) A shake detecting means for detecting a shake component with respect to the optical axis of the optical device, a correction lens for correcting the influence of the shake of the optical device, a position detecting means for detecting a position of the correction lens, A driving unit that drives the correction lens based on each detection information of the shake detection unit and the position detection unit; and a switch detection unit that detects a state of an external switch of the optical device, based on the detection information of the switch detection unit. Thus, the feedback signal from the position detecting means to the driving means is controlled.

(2) In the configuration (1), the shake detecting means detects shake components in the vertical and horizontal directions with respect to the optical axis, and the correction lens corrects the influence of the shake in the vertical and horizontal directions. I made it.

(3) In the configuration of the above (1) or (2), gain control means for controlling the gain of the detection signal of the position detection means is provided, and the gain of the detection signal is adjusted based on the detection information of the switch detection means. I changed it.

(4) In the configuration of the above (3), the switch detecting means detects the state of the power switch, and when the power switch is turned off, the gain control means sets the gain of the detection signal of the position detecting means to a predetermined value. The power supply was cut off after a predetermined value was reduced over time.

(5) A shake correction method for detecting a shake component with respect to the optical axis of an optical device and correcting the influence of the shake of the optical device by a correction lens, wherein the position of the correction lens is detected, and The correction lens is driven based on the detection information and the detection information of the shake component, the state of the external switch of the optical device is detected, and the position detection information of the correction lens is controlled based on the detection information. .

(6) In the configuration of (5), the shake components in the vertical and horizontal directions with respect to the optical axis of the optical device are detected, and the influence of the shake in the vertical and horizontal directions is corrected by the correction lens. did.

(7) In the configuration of (5) or (6), the gain of the position detection information of the correction lens is changed based on the detection information of the external switch.

(8) In the configuration of (7), the state of the power switch is detected, and when the power switch is turned off, the gain of the position detection signal of the correction lens is reduced to a predetermined value over a predetermined time. From the power supply.

(9) A shake detecting means for detecting a shake component of the apparatus main body with respect to the optical axis, a correction lens for correcting the influence of the shake of the apparatus main body, a position detecting means for detecting a position of the correction lens, A driving unit that drives the correction lens based on each detection information of the shake detection unit and the position detection unit; and a switch detection unit that detects a state of an external switch of the optical device, based on the detection information of the switch detection unit. Thus, the feedback signal from the position detecting means to the driving means is controlled.

(10) In the configuration of (9), the shake detecting means detects shake components in the vertical and horizontal directions with respect to the optical axis, and the correction lens corrects the influence of the shake in the vertical and horizontal directions. I did it.

(11) The configuration according to (9) or (10) above, further comprising gain control means for controlling the gain of the detection signal of the position detection means, and controlling the gain of the detection signal based on the detection information of the switch detection means. I changed it.

(12) In the configuration of (11), the switch detection means detects the state of the power switch, and when the power switch is turned off, the gain control means determines the gain of the detection signal of the position detection means by a predetermined value. The power supply was cut off after a predetermined value was reduced over time.

[0025]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention. The same reference numerals as in FIG. 6 denote the same components.

In FIG. 1, reference numeral 101 denotes an angular velocity sensor (vibration detecting means) for detecting vibration components in a vertical direction and a horizontal direction with respect to the optical axis of a device such as a video camera which is an optical device, and outputs an angular velocity signal corresponding to the vibration. Output. This angular velocity signal is input to the angular velocity sensor amplifier 103 via the HPF 102, amplified there, and
Is input to the A / D converter 105 in the IS microcomputer 111 and is converted into a digital signal.

The digitized signal is supplied to the HPF 10
6. A signal representing the target value of the shake correction passes through the phase compensation circuit 107 and the integrator 108, is input to the LPF 112 via the changeover switch 110, and then is added to the adder 113.
Is input to The output of the adder 113 is a signal corresponding to the above-described shake detection result, and the driver (driving means) 114 controls the position of the shift lens 115 as a correction lens group for shake correction according to this signal.
Thereby, the influence of the shake of the device main body movable in the vertical direction and the horizontal direction with respect to the optical axis is corrected. When the shake correction is off, the fixed output signal of the output fixing circuit 109 is input from the changeover switch 110 to the LPF 112,
No shake correction is performed.

The position of the shift lens 115 is detected by a position sensor (position detecting means) 116, and the detection signal (position signal) is amplified by a position sensor amplifier 117 and input to the adder 113 as a feedback signal. The ON / OFF state of a power switch 118, which is an external switch of the device, is detected by a mode microcomputer (switch detection means) 119, and an information signal corresponding to the detection result is output to the IS microcomputer 11 by the mode microcomputer.
1 is input from the gain control circuit (gain control means) 120 to the position sensor amplifier 117, and its gain (gain)
Is changed. Thereby, for example, the power switch 118
Is detected, the gain of the position sensor amplifier 117 is reduced to a predetermined value by the gain control circuit 120 over a predetermined time, and thereafter, the power is controlled to be cut off.

Here, in the configuration of FIG.
Reference numeral 08 denotes a shake detection system signal processing circuit.
To 117 constitute a shake correction system circuit. The mode microcomputer 119 monitors the state of each switch of the device and controls the mode transition of the device. The position sensor amplifier 117 varies the gain around the reference potential according to the set value from the gain control circuit 120. It can be made to be.

When a power-off request is generated by a user's operation or the like, the gain of the position sensor amplifier 117 is gradually reduced as described above, so that the shift lens 115 shifts in the direction in which gravity is applied. The gain is reduced until the sound generated by completely stopping the control of the shift lens 115 and hitting the lens barrel moves to a position where the sound does not matter or moves to the mechanical end (the inner wall of the lens barrel).
Then the power is turned off.

FIG. 2 is a sectional view showing a simple structure of a lens having the above-described shake correcting function. In FIG.
Denotes a lens barrel, 202 denotes a fixed first lens group, 203 denotes a second lens group for performing a variable power operation, 207 denotes an aperture, and 204 denotes a third lens group for performing shake correction (shift lens 115). Reference numeral 205 denotes a fourth lens group having both a function of correcting a focus shift generated when a variable power lens 203 performs a variable power operation and a function of adjusting a focus. Reference numeral 206 denotes an image pickup device. It will be imaged.

FIG. 3 simply shows the shift position of the shift lens. In the figure, reference numeral 301 denotes the inner wall of the lens barrel (mechanical end), and the center position of the shift lens is the position A. In this embodiment, the shift lens is gradually moved to the mechanical end (B) in order to prevent the shift lens from hitting the end of the lens barrel and generating sound.
(Or C position). Here, the predetermined value A of the position sensor amplifier 117 is a gain that is sufficiently low for the shift lens to move to the position of C or to a position at which the sound does not matter even if the shift lens falls under its own weight. The predetermined value B is a gain that is sufficiently low for the shift lens to move. Further, the predetermined value B is a difference amount for moving the shift lens at a speed that does not generate sound due to mechanical end contact.

FIG. 4 shows the correction lens group (shift lens 1).
FIG. 15 is a perspective view showing a unit configuration of a third lens group 204) which is No. 15;

In FIG. 4, reference numeral 9 denotes a holding frame for the correction lens group. The holding frame 9 has three guide pins 11a and 11a.
As shown in the figure, b and 11c are integrally held by press-fitting, bonding, or the like.
They are arranged at 20 ° intervals. Also, the guide pin 11
Reference numerals a, 11b, and 11c are engaged with the guide portions coming out of the intermediate lens barrel 5, respectively. This guide portion fits in the optical axis direction and has an elongated hole in the circumferential direction.

A guide plate 16 is provided between the intermediate lens barrel 5 and the holding frame 9. The guide plate 16 is provided with two pairs of elongated holes 16a and 16b whose central axes are perpendicular to each other. They are fitted with pins projecting from the intermediate lens barrel 5 and the holding frame 9, respectively. With the above configuration, the holding frame 9 is positioned with respect to the intermediate lens barrel 5 in the optical axis direction and the rotation direction (roll direction) with respect to the optical axis center, and the lateral direction (yaw direction), It is guided so as to be rotatable only in the vertical direction (pitch direction).

Here, a voice coil motor is used to drive the correction lens group in a direction perpendicular to the optical axis. Magnets 13a and 13b and back yokes 12a and 12b that are in contact with the magnets are fixed to the intermediate lens barrel 5, and the upper yoke 15 is also fixed to the intermediate lens barrel 5 so as to have a certain distance from the magnets. These may be based on adhesion or magnetic biasing force between the magnets 13a and 13b and the upper yoke 15. The coils 14a and 14b are arranged between them, and are held integrally with the holding frame 9.

The coils 14a, 14 thus constructed
When an electric current is passed through b, an electromagnetic force is generated, and the correction lens group is "floated" in the lens barrel so that its center becomes the center of the optical axis, and further, a force for moving in a direction perpendicular to the optical axis. Can be generated.

Since the components constituting the voice coil as described above are arranged in a direction orthogonal to each other by two sets as shown in FIG. 4, a driving mechanism combined with the above-described mechanism is established. Here, as the position detector (position sensor 116) at the time of driving the correction lens group, the magnet 1 is used here.
3a, 13b and Hall elements 18a, 18b are used to face each other. This is described, for example, in JP-A-08-136.
It is equivalent to that disclosed in Japanese Patent Publication No. 207.

In FIG. 4, reference numerals 17a and 17b denote magnets 13a and 13b and a yoke in contact with the magnets 13a and 13b, which are magnetized so as to have a magnetic gradient in the driving direction of the correction lens group. The holes 18a and 18b
a and 17b are arranged at a position facing each other. Reference numeral 19 denotes a sensor holder, which includes Hall elements 18a,
18b, which itself is held by the intermediate lens barrel 5.
This is also arranged in the direction perpendicular to the two sets, similarly to the actuator.

With the above arrangement, the position of the correction lens group in the driving direction can be detected. However, the position detection method is not limited to this method.
There are various types such as a type provided with a slit between D. In this embodiment, the components shown in FIG. 4 constitute one anti-vibration unit, and the correction lens group for performing shake correction moves vertically and horizontally to the direction perpendicular to the optical axis as shown by arrows in FIG. The optical axis is changed in accordance with the magnitude of the shake to perform shake correction such as camera shake.

FIG. 5 is a flowchart showing the sequence operation of this embodiment. The control processing shown in this flowchart is executed by the IS microcomputer 111 of FIG. 1 in accordance with a program stored in advance.

In the flowchart of FIG. 5, the processing from the start of step S1 to the end of step S10 is repeatedly executed in the IS microcomputer 111 at a predetermined cycle.

In step S2, it is determined whether a power-off request has been issued. This is determined based on the received data obtained by communication with the mode microcomputer 119. The data received from the mode microcomputer 119 is a preset code such as a shake correction ON / OFF request and a power OFF request.

If it is determined in step S2 that there is no power-off request, the flow branches to step S5. Step S2
Then, the normal control which is the control for realizing the normal shake correction is executed, and then the processing is ended.

If it is determined in step S2 that there is a power-off request, the flow branches to step S3. In step S3, it is determined whether or not the power-off request is ready (power OK).

If it is determined in step S3 that the power is off, the process ends. At this stage, it is in a state of waiting for the mode microcomputer 119 to actually shut off the power.

If it is determined in step S3 that the power is not OK, the flow branches to step S4. In step S4, it is determined whether or not the shake correction is off (IS off).

If it is determined in step S4 that IS is not off, the flow branches to step S7. In step S7,
IS-off processing is performed.

If it is determined in step S4 that IS is off, the flow branches to step S6. In step S6, it is determined whether or not the position sensor gain is larger than the predetermined value A.

If it is determined in step S6 that the position sensor gain is larger than the predetermined value A, the flow branches to step S9, and the process is terminated.

In step S9, the aforementioned predetermined value B is subtracted from the position sensor gain. By repeatedly executing the process of step S9, the position sensor gain gradually decreases.

If it is determined in step S6 that the position sensor gain is smaller than or equal to the predetermined value A, the flow branches to step S8, and the process is terminated.

In step S8, power off OK is set. This information is included in data transmitted to the mode microcomputer 119. As a result, the mode microcomputer 119 determines that the power supply is ready to be turned off, and turns off the power supply.

As described above, in this embodiment, the power switch 1
The state 18 is monitored, and in response to the change in the state, the shift lens 115 is gradually moved to the mechanical end, and the power is actually turned off after the shift lens 115 reaches the mechanical end. Accordingly, it is possible to prevent the shift lens 115 from dropping under its own weight and make harsh sounds when the power is turned off, and it is possible to improve the quality of the product.

[0055]

As described above, according to the present invention,
By detecting that the external switch of the device has been turned off, and detecting the power-off state, etc., gradually lower the position sensor gain of the shift lens so that the shift lens can be gradually moved regardless of the posture difference of the device. In this way, the shift lens can be moved to the mechanical end, preventing the shift lens from dropping under its own weight and generating harsh sounds, thereby improving the quality of the product.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment of the present invention.

FIG. 2 is a cross-sectional view illustrating a configuration of a lens having a shake correction function.

FIG. 3 is an explanatory diagram showing a shift position of a shift lens.

FIG. 4 is a perspective view showing a unit configuration of a correction length group.

FIG. 5 is a flowchart showing the operation of the embodiment.

FIG. 6 is a block diagram showing a configuration of a conventional example.

[Explanation of symbols]

 101 angular velocity sensor (vibration detecting means) 111 IS microcomputer 113 adder 114 driver (driving means) 115 shift lens (correction lens group) 116 position sensor (position detecting means) 117 position sensor amplifier 118 power switch 119 mode microcomputer (switch detecting means 120) Gain control circuit (gain control means)

Claims (12)

[Claims] 1. A shake detecting means for detecting a shake component with respect to an optical axis of an optical device, a correction lens for correcting an influence of a shake of the optical device, a position detecting means for detecting a position of the correction lens, and the shake Driving means for driving the correction lens based on each detection information of the detection means and the position detection means,
Switch detection means for detecting a state of an external switch of the optical device, wherein a feedback signal from the position detection means to the drive means is controlled based on detection information of the switch detection means. Correction device. 2. The apparatus according to claim 1, wherein the shake detecting means detects shake components in the vertical and horizontal directions with respect to the optical axis, and the correction lens corrects the influence of the shake in the vertical and horizontal directions. Optical image stabilizer. 3. A gain control means for controlling a gain of a detection signal of a position detection means, wherein the gain of the detection signal is changed based on detection information of the switch detection means. For optical equipment. 4. The switch detecting means detects the state of the power switch, and when the power switch is turned off, the gain control means reduces the gain of the detection signal of the position detecting means to a predetermined value over a predetermined time. 4. The apparatus according to claim 3, wherein the power supply is shut off. 5. A shake correction method for detecting a shake component of an optical device with respect to an optical axis and correcting the influence of the shake of the optical device by a correction lens, wherein the position of the correction lens is detected, and the position is detected. The correction lens is driven based on the information and the detection information of the shake component, the state of the external switch of the optical device is detected, and the position detection information of the correction lens is controlled based on the detection information. A shake correction method for an optical device, comprising: 6. The apparatus according to claim 5, wherein a shake component in a vertical direction and a horizontal direction with respect to an optical axis of the optical device is detected, and the influence of the shake in the vertical direction and the horizontal direction is corrected by a correction lens. The shake correction method of the optical apparatus described in the above. 7. The method according to claim 5, wherein the gain of the position detection information of the correction lens is changed based on the detection information of the external switch. 8. The method according to claim 1, wherein the state of the power switch is detected, and when the power switch is turned off, the gain of the position detection signal of the correction lens is reduced to a predetermined value over a predetermined time, and then the power is shut off. The method of correcting a shake of an optical device according to claim 7. 9. A shake detecting means for detecting a shake component with respect to an optical axis of the device main body, a correction lens for correcting an influence of the shake of the device main body, a position detecting means for detecting a position of the correction lens, and the shake Driving means for driving the correction lens based on each detection information of the detection means and the position detection means,
An optical device, comprising: switch detection means for detecting a state of an external switch of the optical device; and controlling a feedback signal from the position detection means to the driving means based on detection information of the switch detection means. 10. The apparatus according to claim 9, wherein the shake detecting means detects shake components in the vertical and horizontal directions with respect to the optical axis, and the correction lens corrects the influence of the shake in the vertical and horizontal directions. Optical equipment. 11. The gain control means for controlling the gain of the detection signal of the position detection means, wherein the gain of the detection signal is changed based on the detection information of the switch detection means. Optical equipment. 12. The switch detecting means detects the state of the power switch, and when the power switch is turned off, the gain control means reduces the gain of the detection signal of the position detecting means to a predetermined value over a predetermined time. The optical device according to claim 11, wherein the power supply is shut off from the power supply.