JPH05203895A - Shake preventive device - Google Patents

Abstract

PURPOSE:To save a space and cost by unitizing the image shake preventive device by a camera shake, etc., by a simple construction, thereby constituting this device. CONSTITUTION:This device has a shake preventive optical system 8 which is moved in the direction orthogonal with an optical axis 1. This device is provided with 1st, 2nd motors 30, 31 for driving a lens frame 6 which is driven by control means 72, 73 and holds the shake preventive optical system in 1st and 2nd directions upon detection by shake detecting means 60x, 60y. The 1st motor 30 drives the lens frame in the 1st direction and has a 1st connecting member 36 for connecting the lens frame movably in the 2nd direction regardless from the 1st motor 30. The 2nd motor 31 drives the lens frame 6 in the 2nd direction and has a 2nd connecting member 37 for connecting the lens frame movably in the 1st direction regardless of the 2nd motor 31. The 1st and 2nd motors 30, 31 are disposed to intersect orthogonally with the optical axis in the directions different in the circumferential direction of the outer peripheral part of the lens frame from the 1st and 2nd connecting members 36, 37.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shake prevention device suitable for use in a camera or the like to prevent image shake due to camera shake.

[0002]

2. Description of the Related Art Currently manufactured cameras are highly automated due to remarkable digitization in various parts such as an automatic exposure mechanism and an autofocus mechanism. But,
As an unsatisfactory part of an attempt to automate this type of camera, there is a countermeasure against an image blur caused by a camera shake during hand-held photographing and the like. That is, in the conventional camera of this type, the following proposals have been made only to the problem of image blur.

To briefly explain this, in order to take a proper picture, it is necessary to consider the influence of camera shake on the side of the photographer who holds the camera. On the basis of the detection result, a warning of the shake state is performed under the condition where the shake occurs.

In addition, on the basis of the detection result of the above-mentioned shake detecting means, there is also one which controls so that photographing cannot be performed under the shake occurrence condition, for example, US Pat.
No. 96 specification and the like.

Further, there is also a camera in which the camera is attached to a vibration-proof stand capable of cutting off vibrations from the outside, thereby preventing the influence of shake.

There is also known a camera equipped with a gyro which generates an inertial force.

[0007]

However, the conventional measures against the image blur as described above cannot avoid the following problems.

That is, it is possible to confirm that there is shaking by simply displaying a warning of the shaking, but it is not possible to avoid the shaking directly and to take a picture without shaking.

Further, if the photographing cannot be performed while the camera shakes, the photographing conditions will be limited and the photograph desired cannot be taken.

Further, if an anti-vibration table or a gyro is used, not only the whole size becomes large but also the price becomes high, which is not suitable for a small camera using a 35 mm film, for example.

For this reason, some of the optical systems movably control a part of the optical system as a shake correction optical system according to the detection result of the shake detecting means to prevent image shake on the film image forming surface as much as possible. Although proposed, the structure of this correction mechanism is complicated, and not only does the overall size increase, but it also has a problem in movably controlling the correction optical system to the required state. It is hoped that some measures will be taken to eliminate this.

In view of such circumstances, the present invention can surely prevent image shake due to camera shake, etc., has a simple structure, does not cause an increase in size, and can be easily incorporated into a restricted space. The cost is also low, and the object is to obtain a suitable shake prevention device by applying it to a camera with a 35 mm lens shutter, for example.

[0013]

In order to meet such a demand, a shake preventing apparatus according to the present invention is provided with a shake preventing optical system which is movable in a direction orthogonal to an optical axis of a main optical system to prevent shake. A drive mechanism that drives the anti-shake optical system by being driven by the control means according to the detection result of the shake detection means for detecting the shake, and the drive mechanism includes a lens frame member that holds the anti-shake optical system. The first drive means drives in the first direction, and the second drive means drives the lens frame member in a second direction different from the first direction. Means for driving the lens frame member in the first direction and for irrespective of the first driving means, the second means.
Of the first driving means, the second driving means drives the lens frame member in the second direction and is independent of the second driving means. 1 has a second connecting member for connecting in a movable state in the direction of 1, and these first and second connecting members,
The outer periphery of the lens frame member that holds the shake prevention optical system is movably disposed, and the first and second driving means are arranged at the outer periphery of the lens frame member that holds the shake prevention optical system. At a position different from the connecting member of 2 in the circumferential direction,
It is arranged in a positional relationship orthogonal to the optical axis of the shake prevention optical system.

Further, according to the present invention, the first and second motors are used as the first and second driving means, and the first and second motors are rotated by the rotational movements of their respective output shafts. It is configured to have first and second conversion means for converting linear motion in the first and second directions, and the output shafts of the first and second motors are respectively the first and second. It is arranged so as to be parallel to the direction of.

[0015]

According to the present invention, the anti-shake optical system is caused to pass through the lens frame member by the driving force from the first and second drive means which are drive-controlled in a required state by the shake detection means and the control means. Can be moved in the first direction and the second direction respectively, whereby the shake prevention optical system can be arbitrarily driven in the combined direction to prevent shake.

Further, according to the present invention, the first and second driving means and the first and second connecting members are provided in a desired state around the outer peripheral portion of the lens frame member holding the shake preventing optical system. It can be installed as a unit and can be installed efficiently, and can be installed adjacent to other complicated mechanical parts.

[0017]

1 to 6 show an embodiment of a shake preventing apparatus according to the present invention. In these drawings, first, a photographing lens system with a lens shutter to which the present invention is applied is provided. The schematic configuration of the camera will be briefly described with reference to FIG.

That is, in the camera indicated by reference numeral 1 as a whole, the taking lens system 2 includes three lenses 4a, 4b and 4c.
Is held by the lens frame 3 and a first lens group 4 and three or four lenses 7a, 7b, 7
c; 8a, 8b, 8c, and 8d are held by the lens frames 5 and 6, and a second lens group 9 including a total of seven lenses by the front and rear lens groups 7 and 8; Third lens group 11 configured by holding the lenses 11a, 11b, 11c on the lens frame 10
And a zoom lens composed of.

Reference numeral 12 in the figure denotes a lens shutter provided between the front lens group 7 and the rear lens group 8 of the above-mentioned second lens group 9, and shutter shutters 13 and 14 and a drive for driving them. It is composed of a part 15 and the like. It should be noted that the drive unit 15 is disposed on the outer peripheral portion of the lens frame 5 of the front lens group 7 in the second lens group 9 and further the shutter curtain 1
The lenses 3 and 14 are arranged immediately in front of the rear lens group 8 that functions as an image blur prevention lens described later.

Further, reference numeral 16 in the drawing denotes the first, second and third lens groups 4, 9, which constitute the above-mentioned taking lens system 2.
An image forming surface of a film on which a subject image is formed by 11 and I in the drawing is an optical axis of the taking lens system 2.

According to the present invention, in the taking lens system 2 having the three lens groups 4, 9 and 11 as described above, the rear lens group 8 of the second lens group 9 is replaced by the image stabilizing lens. In order to move the image formed on the image forming surface 16 in accordance with the image shake state by shifting in the direction orthogonal to the optical axis I, the image shake preventing mechanism portion 20 as shown in FIGS. This image blur prevention mechanism unit 20 is used.
2, FIG. 3 and FIG. 6, the substrate 21 on the lens shutter 12 side is provided as a base member in the space on the outer peripheral side of the rear lens group 8 in the second lens group 9. It has features.

This will be described in detail with reference to FIGS. 1 to 3. The rear lens group 8 in the second lens group 9 (hereinafter referred to as the shake prevention lens 8) is fixedly held in the lens frame 6. In this lens frame 6, the flange portion 6a provided on the outer peripheral portion of the lens frame 6 is provided at four positions of the substrate 21 and the lid body 22 provided on the rear end side of the substrate 21 to form an annular space inside. Between the holding part 22a (only two places are shown in FIG. 3) and four front and rear balls (hard balls) 23 and 24 (two places are omitted), respectively. Thus, it is supported inside the opening 21a of the substrate 21 so as to be movable with a low load in the direction orthogonal to the optical axis I. In the figure, reference numerals 25 and 26 denote retainers for holding the balls 23 and 24, respectively, and only four parts are shown and the remaining four parts are omitted.

Reference numerals 30 and 31 denote the image blur prevention lens 8 x.
DC motors for x-axis and y-axis (denoted by Mx and My in the figure) serving as driving means for moving in the axial direction and the y-axis direction, and 32 and 33 are these motors 30 and 31.
Gears 32a, 32b, 32c, 3 for transmitting driving force from the
2d; a gear train for rotation transmission composed of 33a, 33b, 33c, 33d, the rotation of which can be rotated by extending in the x-axis direction and the y-axis direction on bearing portions 21b, 21c provided on the substrate 21. First and second shafts 34 pivotally supported on
35 is transmitted. The motors 30 and 31 described above are fixed to the substrate 21 side, and the gear train 3
Gears 32a, 32b, 32c;
a, 33b and 33c are rotatably fixed on the substrate 21, and the final gears 32d and 33d are respectively attached to the shaft 3
It is configured to be rotatable integrally with 4, 35.

Female threads 36a and 37a provided on the male and female threads 36 and 37 are the male and female thread portions 3 of the shafts 34 and 35, respectively.
X-axis side and y-axis side connecting members screwed to 4a, 35a, the connecting member 36 on the x-axis side is formed with elongated holes 36b, 36c parallel to the y-axis direction. Hole 3
Bosses 6b and 6c provided on the flange portion 6a of the lens frame 6 are engaged with 6b and 36c. Also,
Similarly to the above, the y-axis side connecting member 37 is also formed with elongated holes 37b and 37c parallel to the x-axis direction, and these elongated holes 37b and 37c are also provided with the flange portion 6a of the lens frame 6.
The bosses 6d and 6e provided on the are engaged with each other.

Therefore, the shake prevention lens 8 described above is used.
Is connected to the x-axis side motor 30 through the connecting member 36.
It is driven in the axial direction but free in the y-axis direction. In addition, this shake prevention lens 8 has a similar mechanism
The motor 31 on the shaft side is driven in the y-axis direction via the connecting member 37, but is free in the x-axis direction. Therefore,
The shake prevention lens 8 can be driven in all directions inside the opening 21a of the substrate 21.

By the way, the above-mentioned position detection of the shake prevention lens 8 is performed by the gears 32a and 33a shown in FIGS.
Discs 40x and 40y with holes which are integrally provided with the peripheral portion and are provided with a large number of holes at equal intervals, and a photo interrupter 41x which is provided on the substrate 21 side with the peripheral portion sandwiched therebetween. 41y, the rotation angles of the motors 30 and 31 on the x-axis and y-axis sides are detected, respectively. That is, the position can be detected by detecting the number of holes on the side of the disks 40x and 40y as a pulse signal by the photo interrupters 41x and 41y and counting the number.

The center position of the shake prevention lens 8 is set as follows. That is, FIG. 1 and FIG.
As is apparent from the above, stopper pins 42x and 42y are provided at eccentric positions of the gears 32d and 33d integrally provided on the shafts 34 and 35, and these are provided on both side edges of the bearing portions 21b and 21b on the substrate 21 side. 5 and C at the positions of C and D in FIG. 5, respectively.
The rotation angle of d is restricted within the rotation range between the positions C and D. Then, the center of the rotation range of the gears 32d and 33d is made to coincide with the center position of the shake preventing lens 8, so that the center position of the shake preventing lens 8 is set.

By the image blur prevention mechanism section 20 having the above structure, the rear lens group (anti-vibration lens) 8 of the second lens group 9 shown in FIG. 6 is shifted in the direction orthogonal to the lens optical axis I. Thus, the image formed on the image plane 16 can be moved in a desired state, and as a result, image blurring can be prevented.

Further, according to the image blur prevention mechanism section 20 described above, the DC motors 30 and 31 having a relatively large volume have a positional relationship in which the longitudinal direction thereof is orthogonal to the optical axis I of the photographing lens group 2. As can be seen from FIGS. 2 and 3, the DC motors 30 and 31 are connected to the lens shutter 12 and the third lens group 1 as shown in FIGS.
It is not necessary to project it to the first side, and it is possible to assemble the shake prevention lens 8 on the outer peripheral side of the lens frame 6 in high density and compactly, which is advantageous in terms of structure and assembly.

Therefore, according to such an image blur prevention mechanism section 20, the space of the lens shutter 12 and the space between the second lens group 9 and the third lens group 11 are not damaged. Moreover, as described above, the unitization can be easily performed, so that it is excellent in assembling, and is very effective even if it is arranged adjacent to the diaphragm mechanism in, for example, an interchangeable taking lens.

FIG. 7 shows a circuit block for controlling the image blur prevention mechanism section 20 described above. In FIG. 7, reference numeral 60x is a shake for detecting the vertical angular velocity ωx of the camera by a known angular velocity sensor. The sensor, 60y is a known angular velocity sensor, and the angular velocity ω in the left-right direction of the camera is
A shake sensor that detects y, and these sensors 60x, 6
When the respective angular velocities ωx and ωy are detected at 0y, the processing circuit 61 converts these into the moving velocity of the image on the image plane.

The conversion processing by the processing circuit 61 will be described below with reference to FIG. That is, when the distance from the lens L to the object is a, the distance to the image forming surface is b, and the focal length of the lens L is f, the angular velocity of the camera is an imaging formula.

[0033]

[Equation 1]

From the relationship, if the optical axis I is tilted up to I'at the angular velocity ω, the moving velocity v of the image on the image plane at this time is v.
Is the direction of the arrow is positive,

[0035]

[Equation 2]

It can be represented by Therefore, in the vertical direction of the camera,

[0037]

[Equation 3]

In the left-right direction of the camera,

[0039]

[Equation 4]

[0040]

Next, the drive circuit 62 includes the DC motor 30,
31 is controlled to drive the anti-shake lens 8 so as to cancel the velocities vx and vy of the respective images. The rotation angles and rotation speeds of the DC motors 30 and 31 at this time depend on the encoder on the x-axis side (the disk 40x and the photo interrupter 41x) and the encoder on the y-axis side (the disk 40y and the photo interrupter 41y). ), And is fed back to the drive circuit 62 side, and required drive control is performed.

According to the above construction, the first and second motors 30 and 31 can be moved within the annular space formed in the outer peripheral portion of the lens frame 6 of the shake prevention lens 8 in this space. First and second connecting members 3 arranged
6 and 37 are arranged at positions deviated in the circumferential direction such that their longitudinal directions have a positional relationship orthogonal to the optical axis I. The DC motors 30 and 31 serving as drive means can be arranged without projecting to the outside, and the shake prevention mechanism section 20 can be configured as a unit to save the space and cost of the mechanism section 20. And other advantages.

In particular, such an advantage is achieved by the motors 30, 3
The first and second output shafts, which are arranged so as to face the x-axis direction and the y-axis direction, respectively, and whose rotational force becomes first and second conversion means via the gear trains 32 and 33. Axis 3
4, 35 and the first and second connecting members 36, 37 are configured to be converted into linear motions in the x-axis direction and the y-axis direction, respectively. is there.

Further, in the above-described structure, the shake prevention mechanism section 20 uses the case member composed of the substrate 21 and the lid body 22 in the annular space formed on the outer peripheral side of the lens frame 6 of the shake prevention lens 8. It is configured as a unit and has a small size, so that other complicated mechanical parts such as the lens shutter 12 as illustrated in FIG. 6 are required to be arranged adjacent to each other. It can be used to exert an effect.

The present invention is not limited to the structure of the above-described embodiment, and the image blur prevention mechanism section 2 constituting the image blur prevention device.
It goes without saying that the shape, structure, etc. of each part including 0 can be appropriately modified and changed.

For example, in the above-mentioned embodiment, the lens frame member 6 for holding the shake preventing optical system (the shake preventing lens 8).
Is supported by the fixed portion side (substrate 21) via the balls 23 and 24 so as to be slidable with a low load only in the direction orthogonal to the optical axis I. It goes without saying that it is not limited to this. That is, as is clear from FIGS. 9 to 11, the lens holding member 6 is slidably supported on the substrate 21 side via the sliding member 50 made of a material having low friction characteristics such as Teflon or fluororesin. At the same time, the springs 51 and 52 constantly urge and hold the sliding member 50 so that the flange portion 6a on the lens frame member 6 side is always in contact with the sliding member 50 in a slidable state. The sliding member 50 is fixed to the substrate 21 side, and the springs 51 and 52 are stretched between the arm portions 6f and 6g provided on a part of the lens frame member 6 and the substrate 21.

It is needless to say that the sliding member 50 made of such a low-friction material can also obtain the required sliding support state of the lens frame member 6, and the same effect as the above-mentioned embodiment can be obtained. It is what is done.

Further, in the above-described embodiment, the case where the present invention is applied to the camera having the lens shutter 12 has been described, but the present invention is not limited to this, and image blur due to camera shake can be prevented in a conventionally known camera. Optical axis I
Needless to say, it can be applied to an anti-shake lens that shifts in a direction orthogonal to from, and is not limited to the structure on the camera side.

Furthermore, the shake prevention device according to the present invention is not limited to the above-mentioned camera, but can be applied to various optical instruments, devices, etc. to exert its effect.

[0050]

As described above, according to the shake preventing apparatus of the present invention, the drive mechanism driven by the shake detecting means and the control means so that the shake preventing optical system can be moved in the direction orthogonal to the optical axis. Is composed of first driving means for driving the lens frame member holding the shake preventing optical system in the first direction, and second driving means for driving in the second direction different from the first direction. In addition, the first driving means is provided with a lens frame member
Driving the first connecting member movably in the second direction irrespective of the first driving unit to the second driving unit and driving the lens frame member to the second direction. A second connecting member is provided that is movably connected to the first direction regardless of the second driving unit, and the first and second driving units are movable on the outer peripheral portion of the lens frame member of the shake prevention optical system. At a position displaced in the circumferential direction from the free first and second connecting members,
Since they are arranged in a positional relationship orthogonal to the optical axis, even if a DC motor is used as the driving means, the shake prevention mechanism section does not project to the outside despite the simple mechanical structure. Can be configured as a unit, which has various excellent effects such as space saving and cost saving.

In particular, these effects have the first and second conversion means for converting the rotational movement of each output shaft into the linear movement in the first and second directions by using the motor as the driving means. With this configuration, and by arranging the output shafts of the first and second motors so as to be parallel to the first and second directions, respectively, it is possible to further exert the effect.

Further, according to the present invention, since the shake prevention mechanism section can be made compact and unitized, there is an advantage that other complicated mechanism sections such as a lens shutter and a diaphragm mechanism can be arranged adjacent to each other.

Further, according to the present invention, the lens frame member holding the shake preventing optical system is made of a low friction material so that the lens frame member can be slid with a low load only in the direction orthogonal to the optical axis. Since it is supported to the fixed portion side via the means, it is possible to move the shake prevention optical system in a direction orthogonal to the optical axis with a low load, and thereby the first
Further, there is an advantage that it can be moved in a desired state in the combined direction by the driving means for driving in the second direction (that is, the x-axis direction and the y-axis direction).

[Brief description of drawings]

FIG. 1 shows an embodiment of a shake prevention device according to the present invention,
FIG. 6 is a cross-sectional view of a main portion of a shake prevention mechanism portion that is a main portion of a lens barrel portion of a camera.

FIG. 2 is a sectional view taken along line II-II in FIG.

3 is a sectional view taken along line III-III in FIG.

FIG. 4 is an enlarged view of a main part for explaining a position detecting unit of a shake prevention lens.

FIG. 5 is an enlarged view of a main part for explaining a center position determining method of the shake prevention lens.

FIG. 6 is a schematic configuration diagram for explaining a schematic configuration of a camera with a lens shutter, to which the shake prevention device according to the present invention is applied.

FIG. 7 is a circuit block diagram for explaining a control unit for controlling the shake prevention device according to the present invention.

8 is a schematic explanatory diagram of a shake prevention optical system for explaining control by a control unit of the shake prevention device in FIG. 7. FIG.

FIG. 9 is a cross-sectional view of a main part of a shake prevention mechanism portion in a lens barrel portion of a camera showing another embodiment of the shake prevention device according to the present invention.

10 is a cross-sectional view taken along line XX of FIG.

11 is a sectional view taken along line XI-XI of FIG.

[Explanation of symbols]

 1 Camera 2 Photographic Lens System 4 First Lens Group 6 Lens Frame (Lens Frame Member) 6a Flange 6b Boss 6c Boss 6d Boss 6e Boss 7 Front Lens Group 8 Rear Lens Group (Anti-shake Lens) 9 Second Lens Group 11 Third Lens Group 12 Lens Shutter 15 Lens Shutter Drive Unit 16 Image Forming Surface by Film 20 Image Shake Prevention Mechanism Unit 21 Substrate 21a Opening 21b Bearing 21c Bearing Part 22 Lid 23 Ball (Hard Ball) 24 Ball (Hard Ball) 30 x-axis DC motor (driving means) 31 y-axis DC motor (driving means) 32 Driving force transmission gear train 32d Final gear 33 Driving force transmission gear train 33d Final gear 34 First shaft (one of conversion means 34a male screw portion 35 second shaft (constituting a part of conversion means) 35a male screw portion 36 x-axis side Connecting member 36a Female screw portion 36b Long hole 36c Long hole 37 y-axis side connecting member 37a Female screw portion 37b Long hole 37c Long hole 40x Disc with hole 40y Disc with hole 41x Photo interrupter 41y Photo interrupter 42x Stopper pin 42y Stopper Pin 50 Sliding member (sliding means made of low friction material) 51 Spring 52 Spring 60x Shake sensor on x-axis side 60y Shake sensor on y-axis side 61 Processing circuit 62 Drive circuit I Optical axis of photographic lens system

Claims (4)

[Claims] 1. A shake detecting unit for detecting shake, a shake preventing optical system which is movable in a direction orthogonal to an optical axis of a main optical system so as to prevent the shake, and a shake preventing optical system is driven. A shake prevention device comprising a drive mechanism and a control means for controlling the drive mechanism so as to prevent shake according to the detection result of the shake detection means, wherein the drive mechanism is a lens that holds the shake prevention optical system. The first driving means drives the frame member in a first direction, and the second driving means drives the frame member in a second direction different from the first direction. Has a first connecting member that drives the lens frame member in a first direction and is movably connected in a second direction irrespective of the first driving means, and The second driving means includes the lens frame member as the second driving means. Has a second connecting member which is driven in the first direction and is movably connected in the first direction irrespective of the second driving means. These first and second connecting members are The lens frame member that holds the shake prevention optical system is movably disposed on the outer periphery of the lens frame member that holds the shake prevention optical system, and the first and second driving means include a lens frame member that holds the shake prevention optical system. At the outer periphery, the first and second
The shake prevention device is arranged at a position different from the connecting member in the circumferential direction in a positional relationship orthogonal to the optical axis of the shake prevention optical system. 2. The shake prevention device according to claim 1, wherein first and second motors are used as the first and second driving means, and the first and second motors are respectively provided. A first and a second conversion means for converting the rotational movement of the output shaft into a linear movement in first and second directions, and the output shafts of the first and second motors are respectively A shake preventing device, which is arranged so as to be parallel to the first and second directions. 3. The shake prevention device according to claim 1, wherein the first and second motors are arranged adjacent to each other on an outer peripheral portion of a lens frame member holding the shake prevention optical system. Anti-vibration device. 4. The shake prevention device according to claim 1, claim 2, or claim 3, wherein the lens frame member holding the shake prevention optical system can slide with a low load only in a direction orthogonal to the optical axis. The shake prevention device is supported to the fixed portion side through a sliding means made of a low friction material so as to be in a state.