JP2002287196A - Blur correction optical device for image stabilizing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively shut off the unwanted vibration and sound produced by an actuator for correcting an image blur by a simple and inexpensive member. SOLUTION: The blur correction optical device for the image stabilizing device has a foundation member which is disposed within a body tube section, a correction lens which is attached onto the foundation member movably in the perpendicular direction of the optical axis and driving means which is attached to the foundation member and drives the correction lens in the perpendicular of the optical axis. The foundation member is attached by means of an absorption member to the body tube section and the driving means is attached by means of an insulator to the foundation member.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to image stabilization in an image pickup apparatus such as a camera, and more particularly to image stabilization by moving a correction lens in a direction perpendicular to an optical axis to correct an image position. The present invention relates to a shake correction optical device having a function of correcting shake.

[0002]

2. Description of the Related Art Conventionally, as one method for stabilizing an image in an image pickup apparatus such as a camera, an image position is corrected by moving a correction lens in an optical system of the image pickup apparatus in a direction perpendicular to an optical axis. There is a device that corrects image blur due to FIG. 1 of the accompanying drawings shows an example of an optical configuration of an optical image stabilizing apparatus employing such a method. As shown in FIG. 1, the optical configuration includes a front lens 15, a variator 14, a third group fixed system 13, a rear focus 12, and an image sensor 1. In this optical configuration, the zoom is changed by the variator 14, the focus is changed by the rear focus 12, and the image blur is corrected in the direction perpendicular to the optical axis using the third group fixed system 13 as a correction lens. The image position is moved by moving (eccentric movement). Japanese Patent Application Laid-Open No. 63-49729 has already disclosed a proposal in which the correction lens is moved in parallel in the direction perpendicular to the optical axis to move the image position to correct blur. Also, Japanese Patent Application Laid-Open Nos. 10-26881 and 10-260013, and 11-28801
A camera provided with an image blur correction function by a method disclosed in Japanese Patent Application Laid-Open Publication No. 5 (1993) -1993 has been put to practical use. Figure 2 of the accompanying drawings
1 is a plan view of an image blur correction optical system disclosed in Japanese Patent Application Laid-Open No. 11-288015. Also, FIG.
It is sectional drawing in DD of the structure shown in FIG. FIG. 4 is a partial sectional view showing a state in which the image blur correction optical system is mounted on a lens barrel. These FIGS. 2 and 3
As is often shown in FIG. 1, this conventional blur correction optical system supports a lens holder 2 holding a correction lens (correction optical system) 1 so as to be movable on a base member (outer frame) 3. Has become. The lens holder 2 has three legs 2a extending outward from the outer peripheral portion thereof, and the base member 3 is provided with three columns 3a that support each of the legs 2a in a floating manner. I have. The lens holder 2 is fixed to the base member 3 by a spring 4 hung between a latch portion 2b provided at two locations on the outer periphery of the lens holder 2 and a latch portion 3b provided at corresponding locations on the base member 3. It is elastically supported on the top. Furthermore, lens holder 2
, A yoke 6 to which a permanent magnet 5 is connected is attached and fixed. On the other hand, the base member 3 is provided with a coil 7 wound around a bobbin 8 at a position corresponding to each of the permanent magnets 5 attached to the lens holder 2. The permanent magnet 5 and the coil 7 constitute a so-called voice coil motor. By energizing each of the voice coil motors, the lens holder 2 and, therefore, the correction lens 1 held therein are turned on and off. It can be moved in a direction perpendicular to the axis, in this example in the horizontal and vertical directions in FIG.

As shown in FIG. 4, in this conventional example, an outer frame 3 for supporting an actuator called a basic member of a blur correction optical system is firmly fixed to a lens barrel 20. Thus, the base member (outer frame) 3
Is firmly fixed to the lens barrel 20, so that the correction optical system can move with high accuracy.

As described above, a camera that corrects image blur by moving the correction lens in parallel in a direction perpendicular to the optical axis is, with some exceptions, a kind of voice coil motor composed of a magnet and a coil. Normally, correction driving is performed. The reason why the voice coil motor is used is that
This is because the response is fast, it is possible to respond to a high frequency, and the correction lens can be directly driven without a speed reduction mechanism, so that it is extremely excellent as an actuator for blur correction.

[0005]

However, in the configuration of the conventional example described above with reference to FIGS. 2 to 4, when the actuator constituted by the permanent magnet 5 and the coil 7 drives the correction lens 1, the correction lens On the contrary, the thrust for driving 1 acts as a force for moving the coil 7 in the opposite direction. This force acts on the base member 3 (outer frame) via the bobbin 8. When the base member 3 (outer frame) is firmly fixed to the lens barrel 2, this force is directly applied to the lens barrel 2.
It reaches 0. If the lens barrel 20 is sufficiently heavier than the correction lens 1, the amount of movement of the lens barrel 20 is sufficiently small with respect to the amount of movement of the correction lens 1. However, considering the convenience of the photographer, it is preferable that the lens barrel 20 is also light. When the lens barrel 20 is made lighter, as described above, the effect of the reaction of the correction lens increases, and vibration and sound are transmitted to the lens barrel. In addition, even if the voice coil motor used to drive the correction lens has a fast response and can respond to high frequencies, the actuator has a strong thrust to further enhance responsiveness and followability. In such a case, minute noise superimposed on the drive signal drives the actuator, and is transmitted to the surroundings as sound or heard by the photographer. Japanese Patent Application Laid-Open No. 8-262523 discloses a method for blocking sound generated by a correction actuator for driving a correction lens. However, Japanese Patent Application Laid-Open No. 8-262523 discloses that a drive source is supported via a cushioning material in order to cut off such noise.
Japanese Patent Application Laid-Open No. 8-262523 does not use a voice coil motor as a drive source. In addition, Japanese Patent Application Laid-Open No. 8-262523 discloses that a drive source is supported via a cushioning material. No method is disclosed for preventing the correction position control accuracy of the correction lens from deteriorating.

It is an object of the present invention to provide an image stabilizing optical apparatus in an image stabilizing apparatus which can solve the above-mentioned problems of the prior art.

[0007]

According to one aspect of the present invention, in a blur correction optical apparatus in an image stabilizing apparatus, a base member disposed in a lens barrel and an optical axis perpendicular to the base member are provided. A correction lens attached movably in a direction, and a driving unit attached to the base member for driving the correction lens in a direction perpendicular to the optical axis, and the base member is provided with respect to the lens barrel. And is attached via an absorbing member that absorbs shock and vibration.

[0008] According to one embodiment of the present invention, the absorbing member is a flexible member or an elastic member.

According to another embodiment of the present invention, the driving means is a voice coil motor.

According to yet another embodiment of the present invention,
Further, a detecting means for detecting a moving amount of the correcting lens is provided, and the detecting means detects a positional relationship between the correcting lens and the lens barrel.

According to yet another embodiment of the present invention,
Further, a detecting means for detecting a movement amount of the correction lens is provided, and the detecting means detects a positional relationship between the correction lens and the lens barrel, and detects a positional relationship between the correction lens and the base member. To detect.

According to yet another embodiment of the present invention,
A weight member having a specific gravity heavier than the material of the base member is added to the periphery or a part of the base member.

According to yet another embodiment of the present invention,
Furthermore, a locking mechanism for preventing the movement of the correction lens is provided, and the locking mechanism acts so that the correction lens is fixed to the lens barrel.

According to yet another embodiment of the present invention,
The locking mechanism is formed of an annular member as a whole that is configured to be rotatable in contact with the inner surface of the lens barrel, and the correction lens is fixed to the lens barrel on the inner surface of the annular member. Is formed between the locking position where the convex portion performs the fixing operation and the release position where the convex portion does not perform the fixing operation. It can be pivoted.

According to another aspect of the present invention, in a blur correction optical device in an image stabilizing device, a base member disposed in a lens barrel, and mounted on the base member so as to be movable in a direction perpendicular to an optical axis. And a driving unit attached to the base member for driving the correction lens in a direction perpendicular to the optical axis. The driving unit absorbs shock and vibration with respect to the base member. It is characterized in that it is attached via an insulator.

According to one embodiment of the present invention, the insulator is a flexible member or an elastic member formed in a flat plate shape.

According to another embodiment of the present invention, the driving means is a voice coil motor, and a coil and a bobbin of the voice coil motor are attached to the base member via the insulator.

According to yet another embodiment of the present invention,
The driving means is a voice coil motor, and a permanent magnet and a yoke of the voice coil motor are attached to the base member via the insulator.

[0019]

BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described in more detail with reference to the accompanying drawings, in particular with reference to FIGS. 5 to 13, which illustrate embodiments and examples of the invention. Figure 5 of the accompanying drawings
FIG. 5 is a partial cross-sectional view similar to FIG. 4 and showing a configuration of a blur correction optical device in an image stabilizing device as one embodiment of the present invention. The configuration of the shake correction optical apparatus of this embodiment is shown in FIG.
4 is substantially the same as the conventional one described with reference to FIG. 4 except for the following points. Therefore, the same reference numerals as those used in FIGS. Decided not to repeat. As shown in FIG. 5, in this embodiment, the base member 3 (outer frame) to which the actuator (coil 7) is attached is attached to the lens barrel 20 via a member 21 having flexibility.
That is, in this embodiment, a flexible member 21 such as maltprene (rubber sponge) is sandwiched around the outer periphery of the base member 3 (outer frame), and the base member 3 is mounted on the lens barrel 20 to thereby provide an optical axis. The vibration in the vertical direction is absorbed to prevent the transmission of vibration and sound to the lens barrel 20. FIG.
FIG. 6 is a partial cross-sectional view similar to FIG. 5, illustrating a configuration of a shake correction optical device as another embodiment of the present invention. In this example,
The base member 3 is attached to the lens barrel 20 via an elastic member 22 such as rubber. FIG. 7 shows a state in which the elastic member 22 bends and absorbs vibration in this embodiment (the amplitude of vibration that is actually expected to be absorbed is smaller). FIG. 7A is an enlarged view of a left portion of the cross-sectional view of FIG. 6, and FIG. 7B is an elastic member 22 connecting between the base member 3 and the lens barrel 20. It is sectional drawing which shows an example of the attachment method of (1). According to the embodiment shown in FIG. 7, it is easier to bend in a direction perpendicular to the optical axis than in the optical axis direction.
There is an advantage that the inclination of the correction lens hardly occurs. In addition, according to the present invention, the base member is not limited to the flexible member 21 such as moltoprene or the elastic member 22 such as rubber, and may be attached to the lens barrel via an absorbing member that absorbs shock and vibration by deformation. Thus, a similar effect can be obtained. The buffer member such as the elastic member 22 of the base member 3 bends due not only to the vibration accompanying the movement of the correction optical system but also to the gravity applied to the entire base member 3 including the correction optical system. As described above, in order to accurately know the amount of movement of the correction optical system even if the basic member 3 itself that supports the actuator 7 moves, as shown in FIG.
The sensor 24 may be fixedly provided on the lens barrel 20 via the sensor, and the position of the correction optical system may be detected by the sensor 24. By doing so, it is possible to prevent the apparatus from being affected by a position shift or the like due to a posture difference. The sensor 24 for detecting the position of such a correction optical system includes:
In the embodiment shown in FIG. 8, a Hall sensor or the like for detecting magnetism is suitable. If a reflection pattern is provided on the correction optical system side, for example, at a position corresponding to the yoke 6 attached to the lens holder 2, the sensor 2
4 may be an optical sensor for detecting the amount of reflected light. In order to further enhance the effect of blocking vibration, a weight ring 25 may be mounted around the base member 3 as shown in FIG. Assuming that the mass of the moving part including the correction lens 1 and its lens holder 2, the permanent magnet (magnet) 5 and the like is m, and the mass of the fixed parts such as the base member 3 and the coil 7 and the bobbin 8 is n, the moving part moves. As a reaction, the amount by which the fixed portion is moved is as follows.

Condition: The moving amount of the moving portion is a, the moving amount of the fixed portion is a ', and the fixed portion is not subjected to external force. The larger the mass n of the fixed part, the smaller the amount a 'moved as a reaction. Therefore, the amount of deflection to be absorbed by the elastic member is reduced. Further, when the weight ring 25 is provided on the base member 3 as described above, a change in the amount of deflection of the cushioning elastic member due to a difference in the posture of the device increases. If the amount of movement of the correction optical system is detected between the base member 3 and the correction optical system, it is not possible to recognize the difference due to this posture difference. As described above, the weight attached to the base member 3 does not necessarily need to be shaped like the weight ring 25. When a weight such as the weight ring 25 is attached, it becomes difficult for high-frequency components to be transmitted to the lens barrel 20.
It is highly effective as a soundproofing measure. In the present invention,
The locking mechanism for fixing the correction lens so as not to move when the blur correction operation is not performed is not for fixing the correction optical system to the base member 3 but for correcting the lens barrel 20. It is preferable that the optical system be fixed. FIG. 10 shows the embodiment in a plan view similar to FIG. In the embodiment of FIG. 10, the locking mechanism 26
It is an annular member as a whole that is configured to be rotatable in contact with the inner surface of the lens barrel 20. Convex portions A, B, and C as cam portions formed on the inner surface of the locking mechanism 26 hold the three legs 2a extending to the outer peripheral portion of the lens holder 2. The convex portion C of the locking mechanism 26 is configured so that the back surface is lightened to have elasticity. When the projection C pushes the corresponding foot 2a of the lens holder 2 in the inner circumferential direction, the other foot 2a of the lens holder 2 is pressed against the projections A and B of the locking mechanism 26. Since the convex portions A and B are not particularly configured to have elasticity, the pressed convex portions A and B are further pressed against the inner surface of the lens barrel 20, and are pressed against the inner surface of the lens barrel 20. The position is determined accurately. FIG. 10 shows a state in which such a shake correction optical system is locked. Note that the locking mechanism 26 has a clearance with respect to the inner surface of the lens barrel in order to enable rotation. Therefore, in the unlocked state as shown in FIG.
And B do not necessarily press against the inner surface of lens barrel 20. However, it is rotated to the locked state, and FIG.
As described above, the convex portions A and B are pushed by the legs 2a of the lens holder 2 as described above.
6 is slightly deformed, and the rear surfaces of the projections A and B are
It is pressed against the inner surface of.

FIG. 12 is a partial cross-sectional view similar to FIG. 5, showing the configuration of a shake correction optical apparatus as still another embodiment of the present invention. In the above-described embodiment, the base member 3 is moved with respect to the lens barrel 20 by a flexible member 21 or an elastic member 22.
Although it is mounted via an absorbing member that absorbs shock and vibration, in the embodiment of FIG.
Is fixed to the lens barrel 20. Instead, the coil 7 and the bobbin 8 of the voice coil motor as driving means for driving the correction lens 1 in the direction perpendicular to the optical axis,
The base member 3 is attached via the insulator 27. The insulator 27 may be made of a material similar to that of the flexible member 21 or the elastic member 22 and formed in a flat plate shape, and also has a function of absorbing shock and vibration.

FIG. 13 is a partial cross-sectional view similar to FIG. 5, showing the configuration of a shake correction optical apparatus as still another embodiment of the present invention. 12, the coil 7 and the bobbin 8 of the voice coil motor as driving means for driving the correction lens 1 in the direction perpendicular to the optical axis are attached to the base member 3 via the insulator 27. In the embodiment of FIG. 13, the coil 7 and the bobbin 8 of the voice coil motor are mounted on the lens holder 2 side. Instead, the permanent magnet 5 and the yoke 6 of the voice coil motor are connected to the base member via the insulator 27. 3 In this case, both the permanent magnet 5 and the yoke 6 for moving in the vertical direction (Y direction) and for moving in the horizontal direction (X direction) are mounted on the base member 3 via the insulator 27 as an integrated unit. Then it is more effective.

[0023]

According to the structure of the present invention, unnecessary vibration and sound generated by the actuator for correcting image blur can be effectively cut off by a cheap and simple member.

Further, it is possible to perform correction control without lowering the operating position accuracy of the blur correction optical system held via a member that blocks sound.

Further, by adding a weight to the support portion, sound can be more effectively cut off.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an example of an optical configuration of an optical image stabilizer.

FIG. 2 is a plan view showing a conventional example of an image blur correction optical system.

FIG. 3 is a sectional view taken along line DD of FIG. 2;

FIG. 4 is a partial cross-sectional view showing a state where the image blur correction optical system of FIG. 2 is mounted on a lens barrel.

FIG. 5 is a partial cross-sectional view similar to FIG. 4, illustrating a configuration of a shake correction optical apparatus as one embodiment of the present invention.

FIG. 6 is a partial cross-sectional view similar to FIG. 5, illustrating a configuration of a shake correction optical apparatus as another embodiment of the present invention.

FIG. 7 is a diagram showing a state in which the elastic member flexes and absorbs vibration in the embodiment of FIG. 6;

FIG. 8 is a partial cross-sectional view similar to FIG. 5, showing a configuration of a shake correction optical apparatus as still another embodiment of the present invention.

FIG. 9 is a partial cross-sectional view similar to FIG. 5, illustrating a configuration of a shake correction optical apparatus as still another embodiment of the present invention.

FIG. 10 is a plan view similar to FIG. 1, showing an embodiment of the locking mechanism according to the present invention in a locked state.

FIG. 11 is a plan view showing the locking mechanism of FIG. 10 in a released state.

FIG. 12 is a partial cross-sectional view similar to FIG. 5, illustrating a configuration of a shake correction optical apparatus as still another embodiment of the present invention.

FIG. 13 is a partial cross-sectional view similar to FIG. 5, illustrating the configuration of a shake correction optical apparatus as still another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Correction lens 2 Lens holder 2a Foot 2b Latch 3 Base 3a Support 3b Latch 4 Spring 5 Permanent magnet 6 Yoke 7 Coil 8 Bobbin 11 Image sensor 12 Rear focus system 13 Third group fixing system 14 Variator 15 Front lens Reference Signs List 20 lens barrel 21 flexible member 22 elastic member 23 position sensor support member 24 position sensor 25 weight ring 26 locking mechanism A convex portion B convex portion C convex portion 27 insulator

Continued on the front page F-term (reference) 2H044 AE01

Claims (12)

[Claims] 1. An image stabilizing optical device in an image stabilizing device, comprising: a base member provided in a lens barrel; a correction lens mounted on the base member so as to be movable in a direction perpendicular to an optical axis; Driving means for driving the correction lens in a direction perpendicular to the optical axis, the base member is provided with respect to the lens barrel,
An image stabilization optical device, which is attached via an absorbing member that absorbs shock and vibration. 2. The blur correction optical device according to claim 1, wherein the absorbing member is a flexible member or an elastic member. 3. The blur correction optical device according to claim 1, wherein the driving unit is a voice coil motor. 4. The apparatus according to claim 1, further comprising detecting means for detecting an amount of movement of the correction lens, wherein the detecting means detects a positional relationship between the correction lens and the lens barrel. Image stabilization optical device. 5. A detecting means for detecting a movement amount of the correction lens, wherein the detecting means detects a positional relationship between the correction lens and the lens barrel, and detects a positional relationship between the correction lens and the base member. The blur correction optical device according to claim 1, 2 or 3, which detects a positional relationship with respect to the optical axis. 6. The base member according to claim 1, wherein a weight member having a specific gravity heavier than a material of the base member is added to a periphery or a part of the base member. Optical blur correction device. 7. A locking mechanism for preventing movement of the correction lens, wherein the locking mechanism acts so that the correction lens is fixed to the lens barrel. The blur correction optical device according to any one of claims 1 to 6. 8. The locking mechanism comprises an annular member which is rotatable in contact with an inner surface of the lens barrel. The correction lens is provided on the inner surface of the annular member. A convex portion acting to be fixed to the portion is formed, and the annular member has a locking position where the convex portion performs the fixing operation, and a release position where the convex portion does not perform the fixing operation. The blur correction optical device according to claim 7, which can be rotated between the position and the position. 9. A blur correction optical device in an image stabilizing device, wherein a base member disposed in a lens barrel, a correction lens mounted on the base member so as to be movable in a direction perpendicular to an optical axis, and the base member Driving means for driving the correction lens in a direction perpendicular to the optical axis, the driving means being mounted on the base member via an insulator for absorbing shock and vibration. A blur correction optical device characterized by the above-mentioned. 10. The blur correction optical device according to claim 9, wherein the insulator is a flexible member or an elastic member formed in a flat plate shape. 11. The blur correction optical device according to claim 9, wherein the driving unit is a voice coil motor, and a coil and a bobbin of the voice coil motor are attached to the base member via the insulator. . 12. The blur correction optics according to claim 9, wherein the driving means is a voice coil motor, and a permanent magnet and a yoke of the voice coil motor are attached to the base member via the insulator. apparatus.