JPH04180040A - Image blur correcting device for camera - Google Patents

Abstract

PURPOSE:To surely prevent image blurring and to carry out mounting the device in a compact camera by supporting a correcting lens by means of a pair of lens supporting frame which can be moved in parallel in two directions orthogonally crossed, and operating the lens supporting frame with a pair of supporting frame moving mechanisms. CONSTITUTION:When a blurring quantity detecting means detects the quantity of blurring in X- and Y-directions, an operation control circuit outputs the operation control signal of the correcting lens 48. Then, a driving motor 26 moves the correcting lens 48 in a direction where the blurring in the X-direction of the correcting lens 48 is offset, via an X-directional lens supporting frame 13. On the other hand, a driving motor 41 moves the correcting lens 48 in the direction where the blurring in the Y-direction of the correcting lens 48 is offset, via a Y-directional lens supporting frame 16.

Description

DETAILED DESCRIPTION OF THE INVENTION TECHNICAL FIELD The present invention relates to an apparatus for correcting image blur on a film surface that occurs due to blur in the optical axis of a photographing optical system of a camera.

"Prior art and its problems" When taking pictures with a camera hand-held, when the camera is held in an imperfect way or when shooting a dark subject with a slow shutter speed,
Optical axis blur due to camera shake is likely to occur when the photographer is moving while taking pictures. Photos with camera shake are extremely unsightly as the images flow. This camera shake can be prevented to some extent by making the lens brighter, increasing the film sensitivity, and increasing the shutter speed, and by improving the skill of the photographer, but both have their limits.

In order to prevent the occurrence of image blur as described in item 2 above, when camera shake that causes blur in the photographic optical axis occurs, the magnitude of the shake is detected as the angular velocity or angular acceleration applied to the camera, and this angular velocity or angular acceleration is detected. An image blur correction device has been proposed based on the concept of preventing image blur by displacing a correction lens in the direction opposite to the direction in which camera shake occurred in response to acceleration and restoring the camera shake to its original state.

However, in order to easily install this image blur correction device in compact cameras and make it popular, it is essential to develop a device that has a simple structure, can be made compact, and can be made low-cost.

``Object of the Invention'' Therefore, an object of the present invention is to provide an image stabilization device that has a simple structure, can quickly and accurately operate a correction lens according to the amount of camera shake, and can reliably prevent image blur. shall be.

"Summary of the Invention" The present invention provides a shake amount detection means for detecting the amount of shake applied to a camera in two mutually orthogonal directions; a correction lens constituting all or a part of a photographing optical system is moved in parallel in each of the two directions. a pair of lens support frames; a pair of support frame moving mechanisms that move the pair of lens support frames in the two directions; and a correction lens that reduces image blur based on the amount of blur detected by the blur amount detection means. The present invention is characterized in that it includes an operation control means for driving a pair of support frame moving mechanisms to move the support frame in the direction.

“Embodiments of the invention” The invention will now be described with reference to illustrated embodiments.

FIG. 1 is a perspective view showing a first embodiment of an image blur correction device 11 of the present invention, FIG. 2 is a control block diagram thereof, and FIG. 3 is a schematic diagram of a camera 10 to which the image blur correction device 11 is applied. It is a diagram.

A correction lens 48 fixed to the correction lens frame 12 is located after the main photographic lens 24 and forms a photographic optical system together with the main photographic lens 24. This correction lens 4
At the rear of 8, a shake amount detection means 45 consisting of an acceleration sensor is provided.
is provided.

The shake amount detection means 45 may be composed of an angular velocity sensor or an angular acceleration sensor. In this case, the angular velocity sensor or the angular acceleration sensor may be of any type as long as it can detect the magnitude of camera shake, but for example, Angular velocity sensor f FEYK-GO2Cj manufactured by Matsushita Electronic Components Co., Ltd. (
(product number) can be used. This angular velocity sensor utilizes the Coriolis force generated by a vibrating tuning fork, and consists of a gyro signal detection section with two bimorphs arranged in a T-shape, a tuning fork drive circuit, and a signal processing circuit.

The correction lens frame 12 has a cylindrical shape, and a flange portion 12b is integrally formed at the front and rear ends of the optical axis 0 of the cylindrical portion 12a. The correction lens frame 12 is the X-direction lens support frame 1
3 and an X-direction lens support frame 16, and is supported so as to be freely movable in parallel in two orthogonal directions, that is, the x and y directions.

The X-direction lens support frame 13 is formed in a substantially U-shape having a holding portion 13a that slidably holds the cylindrical portion 12a of the correction lens frame 12. A guide bar 15 supported on the photographing lens barrel 14 side is slidably inserted into the upwardly facing open portion of the lens support frame 13.
The directional lens support frame 13 can freely slide in the X direction while supporting the correction lens frame 12 by the clamping portion 13a so as not to prevent the correction lens frame 12 from moving in the X direction. At this time, the correction lens frame 12 is prevented from coming off backward by the flange portion 12b.

Furthermore, a feed nut 17 is fixed below the X-direction lens support frame 13, and a screw shaft 20 is screwed into this feed nut 17. This screw shaft 20 is supported by a rotating shaft part 19 rotatably supported on the photographing lens barrel 14 side along the X direction, and a drive pinion 21 is attached to the end of this rotating shaft part 19. There is. The drive motor 2 is adjacent to the rotating shaft portion 19.
The pinion 23 provided on the rotating shaft of the drive motor 26 transmits its rotation to the drive pinion 21 via the idle gear 22. These drive pinion 21, idle gear 22, and pinion 23 constitute a gear train 25. The drive motor 26, gear train 25, screw shaft 20, and feed nut 17 constitute an X-direction support frame moving mechanism 71.

An MR sensor 29 is provided on the right side of the X-direction lens support frame 13. Flange 12 at the front end of the correction lens frame 12
A permanent magnet 30, which together with the MR sensor 29 constitutes the movement amount detection means 28, is fixed at a position facing the MR sensor 29 in b. This movement amount detection means 28
This utilizes the property that the MR sensor 29 changes its output according to a change in the distance between the MR sensor 29 and the permanent magnet 30.

An X-direction lens support frame 16 is arranged behind the X-direction lens support frame 13. This support frame 16 has the same shape as the X-direction lens support frame 13, and has a 90-degree angle relative to this support frame 13.
It is placed in a rotated position. Similar to the X-direction lens support frame 13, the X-direction lens support frame 16 holds the correction lens frame 12 from above and below with its holding portions 16a,
While restricting movement in the X direction and allowing movement in the X direction, the bar can be moved in the X direction along a guide bar 31 that slides and supports the open portion. During this movement, the correction lens support frame 12 is prevented from coming off forward by the flange 12b at the rear end.

A feed nut 32 is fixed to the X-direction lens support frame 16 on the side opposite to its open portion. A screw shaft 35 is screwed into the feed nut 32. This screw shaft 35 is provided so that its rotating shaft 33 is rotatably supported on the photographic lens barrel 14 side along the X direction orthogonal to the X direction. A drive pinion 36 is provided at one end of the rotating shaft portion 33. Further, a drive motor 41 is provided adjacent to the feed nut 32, and a pinion 39 fixed to the rotating shaft portion 33 of this drive motor 41 is rotated via an idle gear 37 to a drive pinion 36, that is, a screw shaft 35. is being communicated to. These pinion 39, idle gear 37, and drive pinion 36 constitute a gear train 4o. The X-direction support frame moving mechanism 7 is operated by the drive motor 41, gear train 40, screw shaft 35, and feed nut 32.
2 are configured.

MR on one side of the holding part 16a of the X direction lens support frame
Sensor 42 is fixed. A permanent magnet 43, which together with the MR sensor 42 constitutes a movement amount detection means 44, is fixed on the flange 12b at the rear end of the correction lens frame 12 at a position facing the MR sensor 42. Similar to the movement amount detection means 28, this movement amount detection means 44 also has the same function as the MR sensor 4.
2 and the permanent magnet 43.
This changes the output from 2. Note that although the movement amount detection means 28 and 44 were constructed from an MR sensor and a permanent magnet, they may be constructed using a photo ink pen instead. Note that 27 in the figure is a lead wire.

FIG. 2 shows a control system of a camera having the above image blur correction device.

The shake amount detection means 45 is provided on the rear side of the camera 1O as described above, and when it detects the amount of shake applied to the camera 10 in two mutually orthogonal directions, it outputs a signal based on this shake amount.

The operation control circuit (means) 46 outputs a drive signal based on the signal input from the shake amount detection means 45 to the X-direction support frame movement mechanism 71 and the X-direction support frame movement mechanism 72.

The correction lens 48 is moved in a direction to reduce image blur by an X-direction support frame movement mechanism 71 and an X-direction support frame movement mechanism 72 operated by this drive signal.

The movement amount detection means 28 and 44 are connected to the X direction support frame movement mechanism 7.
1 and X, which is moved by the X direction support frame moving mechanism 72.
The amount of movement of the directional lens support frame 13 in the X direction and the amount of movement of the X-direction lens support frame 16 in the X direction are detected, and a signal based on this amount of movement is output to the operation control circuit 46 for feedback.

The tree image blur correction device configured as described above operates as follows.

During photography, when a shake occurs due to pressing down the shutter button, etc., the shake amount detection means 45 detects the amount of shake caused by this shake in two orthogonal directions, that is, the X direction and the X direction, and activates a signal based on this shake amount. It is output to the control circuit 46. Then, the operation control circuit 46 calculates the amount of movement of the correction lens 48 in the x and X directions that can offset the amount of blur in the x and x directions, and outputs an operation control signal based on this.

As a result, the X-direction support frame moving mechanism 71 and the X-direction support frame moving mechanism 72 are driven. That is, the correction lens 48
An applied voltage is outputted to the drive motor 26 and the drive motor 41 so that the moving speed of the camera follows the camera shake speed. Then, the drive motor 26 drives the correction lens 48 to move it in the X direction by a distance that can offset the amount of blur in the X direction at a speed corresponding to the blur speed. Similarly, the drive motor 41 moves the correction lens 48 at a speed corresponding to the shake speed by a distance X that can offset the amount of shake in the X direction.
drive to move in the direction.

Therefore, the screw shaft 20 rotated by the drive of the drive motor 26 moves the X-direction lens support frame 13 via the feed nut 17 in a direction that cancels out the shake in the X direction, and also rotates by the drive of the drive motor 41. The screw shaft 35 moves the X-direction lens support frame 16 via the feed nut 32 in a direction that offsets the shake in the X-direction.

The amount of movement of the incoming lens support frame 13 in the X direction is detected by the amount of movement detection means 44, and the amount of movement of the X direction lens support frame 16 in the X direction is detected by the amount of movement detection means 28. The amount of movement in the X direction and the X direction is determined by using the position to which the correction lens 48 has moved as an xy coordinate point. The amount of movement of the correction lens 48 detected by the amount of movement detection means 28 and the amount of movement detection means 44 is fed back to the operation control circuit 46, and the operation control circuit 46 makes sure that there is no deviation between the amount of blur and the amount of movement of the correction lens 48. Control.

Therefore, according to the present embodiment, the correction lens 48
is supported movably in the X direction and the X direction by the X direction lens support frame 13 and the X direction lens support frame 16, and is supported by the With a simple configuration that only moves in the direction that cancels out the amount of blurring, the correction lens 48 can be moved in all directions to cancel out the image blurring, and it can also be made compact, so it can be used, for example, as a photographic lens. It can be installed in a limited space inside the lens barrel, making it possible to reduce costs.

Next, a second embodiment will be described with reference to FIG. In this embodiment, the structures of the X-direction and X-direction support frame moving mechanisms 71 and 72 in the first embodiment are changed, and with this change, the X-direction lens support frame 13 and the The shape of 16 has also been changed. The same members as in FIG. 1 are given the same reference numerals and their explanations will be omitted.

The X-direction support frame moving mechanism 71' includes guide bars 52 and 53.
It has an X-direction lens support frame 13' that is slidably supported in the X-direction by
A rack 55 is formed on the upper surface along the X direction. A drive motor 26 is arranged adjacent to the X-direction lens support frame 13', and this drive motor 26 is connected to a pinion 56 and an idle gear 5 attached to its rotating shaft.
7, and a gear train 60 consisting of a drive pinion 59, and a rack 55, the
Gives the force of movement in the direction.

The X-direction support frame moving mechanism 72' includes guide bars 63 and 64.
It has an X-direction lens support frame 16' that is slidably supported in the X-direction by
A rack 65 is formed along the X direction.

A drive motor 41 is arranged adjacent to the X-direction lens support frame 16', and this drive motor 41 has a gear train 7o consisting of a pinion 66, an idle gear 67, and a drive pinion 69 attached to its rotating shaft. Also, a moving force in the X direction is applied to the X direction lens support frame 16' via the rack 65.

Therefore, when a camera shake occurs, when a drive signal is output to the drive motors 26 and 41 by the operation control circuit 46 based on the amount of shake detected by the shake amount detection means 45, the drive motors 26 and 41 , the X direction lens support frame 13' and the
6' are moved in the X direction and the X direction, respectively. Similarly to the first embodiment, since it has a simple configuration, it is possible to make it more compact and reduce costs.

"Effects of the Invention" As described above, the present invention supports a correction lens by a pair of lens support frames that are movable in parallel in two directions orthogonal to each other, and supports this lens support frame by a pair of lens support frames that are controlled by an operation control means. Because it is operated by a support frame movement mechanism, the correction lens can be moved in any direction to reduce image blur, and camera shake can be reliably dealt with, even though it has a simple configuration, making it more compact. , it can be installed in a small camera.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of essential parts showing a first embodiment of an image blur correction device for a camera according to the present invention, and FIG. 2 is a block diagram showing a control system of the image blur correction device of FIG. 1. FIG. 3 is a diagram schematically showing the inside of a camera to which the present invention is applied, and FIG. 4 is a perspective view of essential parts showing a second embodiment of the image blur correction device for a camera according to the present invention. 10... Camera, 11... Image blur correction device, 12.
...Correction lens frame, 13.13'...X direction lens support frame, 14...Photographing lens barrel, 15...Guide bar, 16.16'...X direction lens support frame, 17.・
・Feed nut, 19... Rotating shaft portion, 2o... Screw shaft, 21... Drive binion, 22... Idle gear, 23... Binion, 24... Main photographing lens, 25...・Gear train, 26... Drive motor, 27
...Lead wire, 28...Movement amount detection means, 29...
・MR sensor, 30... Permanent magnet, 31... Guide bar, 32... Feeding nut, 33... Rotating shaft portion, 3
5... Screw shaft, 36... Drive binion, 37... Idle gear, 39... Binion, 4o
...Gear train, 41...Drive motor, 42...MR
Sensor, 43... Permanent magnet, 44... Movement amount detection means, 45... Shake amount detection means, 46... Operation control circuit (means), 48... Correction lens, 52.53...・
Guide bar, 56... Binion, 57... Idle gear, 59... Drive binion, 60... Gear train, 6
3.64... Guide bar, 65... Rack, 67.
69... Binion, 7o... Gear train, 71.7F-
X-direction support frame movement mechanism, 72°72'...X-direction support frame movement mechanism. Patent applicant: Kunio Miura, agent of Asahi Optical Industry Co., Ltd. (October 7, 1991) October 7, 1991 1. Display of the case 3. Person making the amendment Relationship with the case Patent applicant address: Tokyo 2-36-9 Maeno-cho, Itabashi-ku, Miyako-ku Name (
052) Asahi Optical Industry Co., Ltd. Representative: Toru Matsumoto 4, Agent address: 11 Niban-cho, Chiyoda-ku, Tokyo 102 Claims column and drawing 6 of the specification, Contents of amendments (1) Patent of the specification The scope of claims is amended as shown in the attached sheet. (2) Figure 3 of the drawings shall be corrected as shown in the attached sheet. A document stating the claims after the above amendments (Japanese Patent Application No. 309497/1999) (1) A blur amount detection means for detecting the amount of blur applied to the camera in two mutually orthogonal directions; All or part of the photographic optical system a pair of lens support frames that move the correction lenses constituting the part in parallel in the two directions, respectively; a pair of support frame moving mechanisms that move the pair of lens support frames in the two directions, respectively; and detection by the shake amount detection means. An image blur correction device for a camera, characterized in that the correction lens is moved in a direction to reduce image blur based on the amount of blur determined; and an operation control means for driving a pair of support frame moving mechanisms. ( 2) In claim 1, the pair of support frame moving mechanisms include a pair of screw shafts supported by the pair of lens support frames respectively along two mutually perpendicular directions and axial movement restricted, and a screw shaft screwed into the screw shafts. An image stabilization device for a camera, which is a pair of feed screw mechanisms having a pair of feed nuts that are coupled together and fixed to a pair of lens support frames, and a pair of drive motors that transmit rotation to the pair of screw shafts. ( 3) In claim 1, the pair of support frame moving mechanisms are only capable of rotation by meshing with a pair of racks fixed to the pair of lens support frames with their tooth surfaces along two directions orthogonal to each other, respectively. An image stabilization device for a camera, which is a pair of rack and pinion mechanisms having a pair of pinion gears supported by H, and a pair of drive motors that transmit rotation to the pair of pinion gears. An image blur correction device for a camera, comprising a movement amount detection device that detects the amount of movement of the pair of lens support frames moved by the support frame moving mechanism and feeds it back to the operation control means. (5) In claim 4, The movement amount detection device includes a pair of MR sensors fixed to a pair of lens support frames, and a pair of M sensors fixed to a pair of lens support frames.
An image stabilization device for a camera that has a pair of permanent magnets fixed to a four-plate frame facing the R sensor. that's all

Claims (5)

[Claims] (1) A shake amount detection means for detecting the amount of shake applied to the camera in two directions orthogonal to each other; a pair of lens support frames that respectively move the correction lens constituting all or a part of the photographic optical system in parallel in the two directions; a pair of support frame moving mechanisms for moving the pair of lens support frames in the two directions, respectively; and a pair of support frame moving mechanisms for moving the pair of lens support frames in the two directions, and based on the shake amount detected by the shake amount detection means, to move the correction lens in a direction to reduce image blur; An image blur correction device for a camera, comprising: operation control means for driving a pair of support frame moving mechanisms. (2) In claim 1, the pair of support frame moving mechanisms include a pair of screw shafts supported by the pair of lens support frames respectively along two directions orthogonal to each other and with restricted axial movement; An image stabilization device for a camera that is a pair of feed screw mechanisms having a pair of feed nuts screwed together and fixed to a pair of lens support frames, and a pair of drive motors that transmit rotation to the pair of screw shafts. (3) In claim 1, the pair of support frame moving mechanisms have a pair of racks fixed to the pair of lens support frames with their tooth surfaces along two directions orthogonal to each other, and are engaged with the pair of racks and only rotate. An image stabilization device for a camera that is a pair of rack and pinion mechanisms having a pair of pinion gears that are supported so that the pinion gears can be supported and a pair of drive motors that transmit rotation to the pair of pinion gears. (4) Image blur correction for a camera according to claim 1, further comprising a movement amount detection device that detects the amount of movement of the pair of lens support frames moved by the support frame moving mechanism and feeds it back to the operation control means. Device. (5) In claim 4, the movement amount detection device includes a pair of MR sensors fixed to a pair of lens support frames, and a pair of MR sensors fixed to a pair of lens support frames;
An image stabilization device for a camera that has a pair of permanent magnets fixed to a pair of lens support frames facing the R sensor.