JP3316864B2 - Image stabilization optical device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera mounted or held on various moving objects, and more particularly to an image blur correcting optical apparatus suitable for use in a camera having a camera shake preventing function in a general still camera.

[0002]

2. Description of the Related Art A part of an optical system (of course, the entire optical system) in an optical device is configured as a correction optical system in order to correct an image blur caused by fluctuations in the optical device. A system in which the correction optical system is moved in a plane perpendicular to the optical axis has already been proposed.

For example, Japanese Patent Application Laid-Open No. 2-120821 discloses an image in which a shake detector and a shake correction optical system are provided, and the shake detector also functions as a detector of the operation amount of the correction optical system. A shake correction device is disclosed.

[0004]

However, the above-described conventionally known correction device can be applied to an ideal thin single lens, but when applied to an interchangeable lens of a lens interchangeable camera, Due to the thickness on the body side, it is inevitable that the installation of a shake detector, which also detects the operation amount of the correction optical system, is difficult in terms of space.

Further, as shown in Japanese Patent Application Laid-Open No. 2-234115, which has been proposed by the present applicant, a lens group having a large number of lenses often used in a still camera or the like is used. In driving for shake correction, there is also a drawback that it is difficult to install a shake detector, which is a problem in terms of space.

Further, in the above-described conventional apparatus, the components of the shake detector are dispersed in the apparatus housing of the optical apparatus and the members constituting the correction optical system, and there is a problem that installation and adjustment are troublesome. In some cases, it is desired to take some measures that can eliminate such problems.

[0007] In particular, the above-mentioned prior art disclosed in Japanese Patent Laid-Open No. 2-1
In the embodiment shown in FIG. 9 in Japanese Patent Publication No. 20821, the distance between the correction optical system (that is, the shiftable imaging lens) and the reflection mirror of the hydrostatic sensor needs to be half of the distance from the film surface.

That is, the shake angle θ and the lens focal length f
Then, the image blur amount D = f × θ (in the case of a long-distance subject, all will be described below under this assumption in the present specification). In this case, the driving amount D ′ of the correction optical system necessary for correcting the image blur amount is D ′ = D in the case of a single lens, and is equal to that of the correction optical system (shiftable imaging lens). Assuming that the distance between the hydrostatic sensor and the reflection mirror is A, 2 × A × θ = f × θ and 2 × A = f must be satisfied.

However, in such a conventional structure, since the space behind the mount position cannot be used in the case of the interchangeable lens, this condition is severe, and it is difficult to satisfy this condition.

Further, in the apparatus having a structure relating to the optical system of the anti-vibration telephoto lens disclosed in Japanese Patent Application Laid-Open No. Hei 2-234115, D ≒ D ′ is usually used for maintaining the optical performance, and furthermore, the correction optical system needs Distance A to A <<
It is necessary to set f, and even if the lens system is integral with the body, the distance of A cannot be ensured. Most ordinary camera lenses have such a configuration,
If D ′ <D, A can be reduced. However, a large departure from “=” results in many difficult problems in optical performance, and such a point must be considered.

[0011]

In order to meet such a demand, an image blur correction optical apparatus according to the present invention is provided with an optical system movably supported in a direction perpendicular to an optical axis to correct image blur. , A driving unit for driving the correction optical system, and a movable unit configured to be operated by the driving unit and performing a motion accompanied by a rotational component when the driving unit is driven. A member, fixed to the movable member, an angular change detection means for detecting rotation with respect to the inertial system,
Control means for controlling the driving of the driving means,
The movable member is provided with an image blur amount d (d = f · θ) at a change angle θ with respect to the optical axis of the optical system whose overall focal length is f.
D '補正 D' = D /
A (where A = coefficient, D = image movement amount) 移動
Moved so that the angle change with respect to the optical system becomes -θ,
By moving the movable member along a radius of curvature set based on the focal length and the characteristic (A) of the correction optical system, the movable member is moved by an amount D ′ of movement of the correction optical system.
, So that it does not always rotate with respect to the inertial system.

Further, according to the present invention, there is provided an adjusting means for adjusting the amount of movement of the movable member by the driving means of the correcting optical system, and the adjusting means is provided with a correcting optical system for correcting image blur. Is rotated in accordance with the movement amount D ′ of the movable member, whereby the amount of movement of the movable member can be adjusted.

Further, according to the present invention, the control means for controlling the driving means for driving the correction optical system is controlled so as to operate the driving means so that the output of the angle change detecting means approaches the static output. When the output of the angle change detecting means is a stationary output, the driving means is controlled so as to maintain the previous operating state.

[0014]

According to the present invention, since the means for driving the image blur correction optical system does not rotate with respect to the inertial system in accordance with the movement amount D 'of the correction optical system, it is mounted. The control unit controls the operation of the driving unit in such a direction that the output of the angle change detecting unit becomes a stationary output, so that the driving for performing appropriate image blur correction by the correction optical system becomes possible.

[0015]

1 to 7 show a first embodiment of an image blur correcting optical apparatus according to the present invention. In these figures, in this embodiment, as shown in FIG. The case where the present invention is applied to the image blur prevention lens (telephoto lens) will be described.

First, an outline of a still camera 2 having a telephoto lens 1 with an image blur prevention function to which the present invention shown in FIG. 1 is applied will be described. In FIG. In the center of the section, a lens barrel 4 that constitutes the telephoto lens 1 is provided. In the lens barrel 4, a fixed lens 5, which is a first group lens, a focusing lens 6, which is a second group lens, and an image blur correction lens 7, which is a third group lens, constituting a photographic lens optical system. Are provided in parallel in the optical axis direction.

The details of such a photographic lens optical system are described in, for example, Japanese Patent Application Laid-Open No. 2-23 which has been previously proposed by the present applicant.
Although this is based on the configuration and the like shown in Japanese Patent No. 4115 and the like, here, for simplification of description, a schematic diagram of a three-group configuration including a convex lens, a concave lens, and a convex lens is shown.

In the above-mentioned optical system, the image blur correction lens 7 as the third group lens is disposed so as to be movable in a plane perpendicular to the optical axis, and this movement is used to correct the image blur caused by the camera swing. It has become.

In the figure, reference numeral 8 denotes a film. The still camera 2 is provided with various mechanical components necessary for the camera, such as a release button and the like, but the details are well known and will not be described.

FIGS. 2 to 5 show the details of the image blur correction lens 7 and its driving mechanism 10 constituting the image blur correction optical system which characterizes the present invention. In these figures, the principal part configuration will be described mainly with reference to FIG.
Reference numeral 1 denotes a correction optical system frame which holds the above-described image blur correction lens 7 and functions as a Y stage by moving vertically in FIG.
Is an X stage that can be moved in the vertical direction in FIG. 2 and that can be moved in the horizontal direction in FIG.
The correction optical system frame 11 is sandwiched and held from the left and right, and has a function of guiding the correction optical system frame 11 in the Y direction. Note that the correction optical system frame 11 has a nested structure and is configured to prevent (falling in a direction perpendicular to the paper surface).

Numeral 13 is arranged so as to surround the outside of the X stage 12. The X stage 12 is held movably in the left-right direction in the figure, and is sandwiched and held from above and below. The fixed frame 13 is fixed to the lens barrel 4 (housing) of the telephoto lens 1 as an optical device. In the drawing, reference numerals 14a, 14b, and 14c denote guide claws provided inside the fixed frame 13 each of which is a pair of two. In the wrong direction).

Reference numeral 15 denotes a Y drive slider, which has an arc shape with a radius of rotation R (described later with reference to FIG. 6), as is apparent from FIG. Are provided so as to be movable. Also, this Y
The cylindrical protrusion 15a protruding from a part of the drive slider 15 is a long hole 11a of the correction optical system frame 11 (see FIG. 5).
The correction optical system frame 11 is driven by the Y drive slider 15 in the Y direction. In the drawings, reference numerals 13b and 13c denote guide rail portions which engage with the guide grooves of the Y drive slider 15.

Here, the turning radius R of the Y-drive slider 15 forming an arc will be described later with reference to FIG. 6 and the like.
The center of the cylindrical projection 15a provided in a part of
It is a necessary condition in the present invention to be located on the locus of the turning radius R.

Further, a gear is cut off at the inner edge of the arc of the Y drive slider 15, and a Y drive pinion gear 16 meshing with the gear is provided and fixed, as is apparent from FIGS. Motor mount 1 outside frame 13
It is designed to be rotationally driven by a Y-drive motor 17 provided via 7a.

Numeral 18 is integrally attached to a part of the Y drive slider 15 provided with the cylindrical projection 15a located on the locus of the rotation radius R as described above. Is a pitching gyro (sensor) as angular change detecting means for detecting rotation around the gyro. The gyro 18 detects the rotation angular velocity (pitching angular velocity) about the X axis of the optical device according to the present invention. It has become. Here, as the pitching gyro 18, a known vibrating bar type gyro may be used.

Reference numeral 19 denotes an X drive slider, 20 denotes an X drive pinion gear, 21 denotes an X drive motor, 22 denotes a yaw angular velocity meter.
5 to 18), and a specific description thereof is omitted. Here, on the X-axis side, a yaw angular velocity meter 22 composed of a well-known vibrating bar type angular velocity meter or the like is used as an angular change detection means, and the rotational angular velocity (yaw angular velocity) around the Y axis of the apparatus of the present invention is detected. It has become.

Reference numeral 23 denotes a drive control unit for driving the Y-axis side and the X-axis side, which comprises a CPU, a motor power supply unit, etc., and based on the outputs of the pitching angular velocity meter 18 and yawing angular velocity meter 22 described above. , And Y
Drive control of the drive motor 17 and the X drive motor 21 is to be performed.

In describing the operation of the apparatus having the above configuration, conditions in the optical system will be described below. First,
In FIG. 1 described above, the image movement amount D on the image plane corresponding to the shift amount D ′ of the image blur correction lens 7 as the third group lens with respect to the optical device (entire optical system) is represented by the following equation. Can be expressed.

D '= D / A D = A.times.D' (A: proportionality constant) (1)

Further, in the image movement due to the change in the angle of the optical axis of the optical apparatus (entire optical system), when the focal length of the entire optical system is f, the image blur amount d at the change angle θ with respect to the optical axis. Is as follows: d = f × θ (2)

However, the image movement caused by the movement of the principal point of the optical system of the entire optical device is usually (when the imaging magnification β << 1).
Since the image blur amount d due to the change in the optical axis angle in the above equation (2) is small, it is ignored.

Therefore, a correction optical system (image blur correction lens 7) is provided to the optical apparatus so that d = -D is always satisfied.
, It is possible to correct the image blur caused by the rotation of the optical axis in the optical system. Assuming that the moving amount of the correction optical system for correcting the image blur amount d is D ', the moving amount D'
Is given by the following equation (3).

D ′ = − (f × θ) / A = −θ × (f / A) (3)

The driving mechanism 10 for the correction optical system (image blur correction lens 7) described with reference to FIGS.
FIG. 6 schematically shows the Y drive slider 15 (the same applies to the X drive slider 19).

That is, the Y drive slider 15 is formed in an arc shape as described above,
It is rotatable with respect to r. The center of the cylindrical projection 15a of the Y drive slider 15 for driving the correction optical system frame 11 is located at the position of the radius of rotation R. In the example of FIG. 6, the sensitivity axis of the pitching gyro 18 is also located on the locus of the radius of rotation R.

Now, the value of the turning radius R is set as follows. R = f / A (4) Then, the equation (4) is combined with the equation (3). D ′ = − θ × R (5)

The condition of the expression (5) is satisfied by moving the Y drive slider 15 by -θ rotation with respect to the rotation center Or when the optical axis of the optical device changes by an angle of θ. . This means that the angular position with respect to the rotation center Or is always constant in the spatial coordinate system (inertial system), that is, no angular velocity is generated. Here, the parallel movement of the optical device, that is, the rotation center Or is ignored as described above.

Therefore, the drive controller 23 controls the Y control so that the angular change output of the pitching gyro 18 fixed to the Y driving slider 15 always disappears, in other words, the output of the pitching gyro 18 becomes a stationary output. Drive motor 1
By driving the slider 7 to control the position of the Y drive slider 15, image blur correction relating to pitching can be achieved.

Strictly speaking, according to this mechanism, D '=
sin (−θ) × R, but since the shift amount of the correction optical system is D ′ << R, there is no problem in the above equation (5).

FIG. 7 shows an example of a drive control algorithm performed by the drive control section 23 described above.

First, starting from step (hereinafter abbreviated as S) 100, the output of the pitching gyro 18 is detected in S110.

Next, in S120, the pitching gyro 18
Of the angular velocity (d
θ) is in the negative direction. And
If negative, the process proceeds to S160, and the Y drive slider 15
The drive of the Y drive motor 17 is strengthened in the direction in which the positive angular velocity is applied (the drive voltage is increased) in order to cancel the negative angular velocity. If the angular velocity applied to the Y drive slider 15 is not negative in S120, the process proceeds to S130.

In this step S130, it is determined from the output of the pitching gyro 18 whether or not the angular velocity applied to the Y drive slider 15 is in the plus direction. If it is positive, the process proceeds to S150, and the driving of the Y drive motor 17 is strengthened in the direction in which the negative angular speed is applied so as to cancel the positive angular speed of the Y drive slider 15. If the angular velocity applied to the Y drive slider 15 is not positive in S130, the process proceeds to S140.

In S140, since the angular velocity applied to the Y drive slider 15 is zero, the drive of the Y drive motor 17 is maintained to maintain this state. That is, the control by the drive control unit 23 is kept at the drive condition determined in the previous routine. Of course, if this routine is the first routine, it is assumed that the motor 17 is stopped at first and the stopped state is maintained.

After the above-described steps S140, S150, and S160 are completed, one routine is terminated in S170. Note that the routine of S100 to S170 is quickly repeated.

The degree of drive enhancement of the Y drive motor 17 in S120 and S130 may be enhanced by a predetermined degree, but is set in proportion to the absolute value of the detected angular velocity. You may.

Although not shown, a posture detection switch (for example, a combination of a mercury switch capable of detecting the posture of the apparatus and the direction in which gravity is applied) is provided to detect the direction of gravity. If the power supply to the Y drive motor 17 is controlled in consideration of the effect of gravity on the image shake, image blur correction with higher accuracy can be performed. In addition, it is also preferable to perform drive control using a fuzzy control technique that has recently been put into practical use.

Although a simple example of the drive control algorithm in the drive control section 23 has been described above, it is needless to say that the present invention is not limited to this. The image shake correction for yawing in the X-axis direction is exactly the same as the drive control in the Y-axis direction described above, and a description thereof will be omitted.

Further, in the above-described example, the case where an angular velocity meter (sensor) is used as the angle change detecting means is shown, but the invention is not limited to this. For example, JP
An angular acceleration sensor as disclosed in JP-A-4-1918 may be used. That is, it is only necessary to drive and control the correction optical system so that the Y drive slider 15 does not always change the angle with respect to the inertial system. Therefore, the drive control may be performed in a direction to always suppress the occurrence of angular acceleration.

Alternatively, a combination of two acceleration sensors having the same sensitivity axis (the tangential direction of the Y drive slider 15 rotation trajectory) may be used. That is, the acceleration sensor is fixed to the front / rear of the Y-drive slider 15 in the optical axis direction (position where the radius of gyration is large / small) and attention is paid to the output difference between the two. When there is no acceleration component, there is no output difference, and when there is an angular acceleration component, there is an output difference. Therefore, it is only necessary to detect the output difference between the two acceleration sensors and perform drive control in a direction to suppress the output difference.

FIGS. 8 to 10 show a second embodiment of the image blur correcting optical apparatus according to the present invention. In these figures, the same or corresponding parts as those in FIGS. The same numbers are assigned and detailed description is omitted. 8, reference numerals 30 and 31 denote X drive units and Y drive units, which drive the image blur correction lens 7 and the correction lens frame 11 as correction optical systems in the X and Y directions. Since the X and Y driving units 30 and 31 have the same structure, only the Y driving unit 31 will be described below, and the corresponding X driving unit 30 will be denoted by the same reference numeral. Omitted.

Reference numeral 32 denotes a cylindrical Y drive shaft, and 33 (33A, 33A,
33B; hereinafter, such a group is collectively described similarly) is a Y drive shaft support member fixed to both ends of the Y drive shaft 32 by caulking or the like, 34 (34A, 34A).
B) is a Y drive B pin fixed to the Y drive shaft support member 33, 35 is a Y drive arm rotatably fitted to the Y drive B pin 34, and 36 (36A, 36B) are Y drive arms. This is a Y drive O pin fixed to 35.

9 and 10, reference numeral 37 (37A, 37B) denotes a Y drive C pin fixed to the Y drive shaft support member 33, and 38 (38A, 38B) denotes Y.
The Y drive unit support member 39 rotatably fitted to the drive O pin 36 and fixed to the housing (lens barrel 4) of the optical device of the present invention, and 39 is an image blur correction lens 7 which is a correction optical system. The weight of the Y drive unit 31 including the Y drive O pin 36 around the Y drive O pin 36 is set so as to cancel the couple due to its own weight, and the Y drive arm 35
This is a Y drive unit balancer fixed to.

Further, in FIG. 9, reference numeral 40 denotes a Y-drive worm wheel fixed to the Y-drive arm 35, and 41 denotes a Y-drive worm meshed with the Y-drive worm wheel 40.
Reference numeral 2 denotes a Y drive motor that drives the Y drive worm 41.

Reference numeral 43 denotes a Y detection arm to which the pitching gyro 18 is fixed, 44 denotes an F pin fixed to an end of the Y detection arm 43 and rotatably fitted into a hole of the Y drive shaft support member 33; Reference numeral 45 denotes a G pin fixed to an end of the Y detection arm 43.

In such a configuration, the Y drive bearing portion 46 is fitted with the Y drive shaft 32, and the correction lens 7 is
The drive shaft 32 is freely slidable in the axial direction and the rotation direction. In FIG. 8, reference numeral 47 denotes an X drive bearing corresponding to the Y drive bearing 46.

As is apparent from FIG. 9, the Y drive section support member 38 has a cut 38a in the optical axis direction, and is fitted with the Y drive C pin 37 and the G pin 45. According to such a configuration, the Y driving C pin 37 and the G pin 45 can slide only in the optical axis direction.

FIGS. 11 and 12 schematically show the embodiment shown in FIGS. 8 to 10, and the same parts as those in FIG. 1 are denoted by the same reference numerals. In these drawings, only the portions related to the Y drive system are shown in a simplified manner, but the X drive system in a direction perpendicular to the plane of the drawing, not shown, has the same configuration. Omitted.

In these figures, point A is the Y drive shaft 3
2, point B is a Y drive B pin 34, point C is a Y drive C pin 37, point O is a Y drive O pin 36, point F is an F pin 44 of the Y detection arm 43, and point G is a G pin. 45 is shown.
Further, point D is the Y drive unit balancer 39.

The arm K connecting the points ABC corresponds to the Y drive shaft support member 33, the arm M connecting the points BOD corresponds to the Y drive arm 35, and the arm N connecting the points FG corresponds to the Y detection arm 43. Further, the point F is located between the points B and C on the arm K.

Here, the distance between point A and point B, the distance between point B and point C, and the distance between point O and point B are set to be the same. Further, the distance between the points O and D is set to be considerably larger than the distance between the points A and B. For example, if the distance between points A and B is 1, the distance between points O and D is 10.

Further, when the correction lens 7 serving as the correction optical system is in a neutral state (a state in which the optical axis of the correction optical system coincides with the optical axes of the other optical systems), the points A and O are at the same position. The arms K and M are overlapped and are parallel to the optical axis. 11 and 12 show a state in which the correction optical system (correction lens 7) is driven in the + Y direction by a movement stroke D '.

In the above configuration, if the arm M is rotated counterclockwise around the point O, the arm M rotates the arm K clockwise through the point B, and the correction optical system (image blur correction lens 7) Is moved in the + Y direction. At this time, since the point C can slide only in the optical axis direction, the point A moves only in a plane perpendicular to the optical axis. In addition, such an arm configuration,
It forms a known Scott Russell mechanism in mechanics, the details of which are well known.

Here, the distance between the point A and the point C is L1, the point C is the point F
The distance between the arms is L2, and the length of the arm N (the distance between the points F and G) is L.
3 is assumed. Further, since the movement stroke of the correction optical system (correction lens 7) is D ', the inclination angle φ of the arm K with respect to the optical axis of the optical device is represented by the following equation.

D ′ = L1 × φ (6) Here, the inclination angle η of the arm 33 with respect to the optical axis of the optical device is represented by the following equation. L2 × φ = L3 × η (7) Then, these equations (6) and (7) are combined. D ′ = L1 × L3 × η / L2 (8)

As described in the above equations (1) to (3), the focal length of the entire optical apparatus is f, and the image blur amount d (d = f × θ) at the optical axis change angle θ is: If the correction optical system (correction lens 7) is driven with respect to the optical device so that d = −D (D = A × D ′) always holds, image blur due to rotation of the optical axis of the optical device can be corrected. .

L1 × L3 × η / L2 = − (f × θ) / A (9) Here, considering the condition satisfying η = −θ, the following equation is obtained. L1 × L3 / L2 = f / A (10)

Then, L1, L2, and L3 are (10)
When the condition of the expression is satisfied, as described in the description of the expression (5), when the optical axis of the optical device changes by the angle θ, the arm N (= Y detection arm 43) is moved to the spatial coordinate system (the inertial system). ) Means that the angular position with respect to the rotation center point G is always constant. Note that the parallel movement of the point G is ignored as described above.

Therefore, L1, L2, and L3 are set in the above (10)
If it is set so as to satisfy the expression, the output of the pitching gyro 18 fixed to the Y detection arm 43 always disappears, in other words, the output of the pitching gyro 18 becomes a static output. The drive control unit 23 drives the Y drive motor 42 to control the drive mechanism (Y drive unit 31) of the second embodiment, so that image blur correction relating to pitching is achieved.

For example, f = 300, A (proportional constant) = 1
, L1 = 8, L2 = 0.8 and L3 = 30. Since both θ and η are minute angles, the sine function can be omitted.

The control algorithm in the second embodiment may be the same as that in FIG. Of course, it is not limited to this.

Further, the example in which the point F is located between the points B and C on the arm K has been described. However, the point F may be located between the points O and B on the arm M or between the points O and D. Alternatively, in the above example, the point F is rotatable with respect to the arm K, and the point G is rotatable with respect to the apparatus housing (the lens barrel 4). It is slidable (a slit is formed in the arm K in the longitudinal direction of the arm fitted to the F pin 44), and the point G is rotatable with respect to the apparatus housing (G pin 3
7 is received in a hole).

If the condition that the angular position of the arm N with respect to the rotation center point G is always constant in the spatial coordinate system (inertial system) is satisfied, the present invention is not limited to the above mechanism. , Point C and point G are not arranged on a straight line.

Therefore, in the image blur correction optical apparatus having the above-described configuration, as shown in FIG. 13, for example, the connection between the arm K and the arm N at the point F is performed via the added small arm P. It will be easily understood that this may be done. Here, the points F and H at both ends of the arm P are rotatable. In that case, it is preferable that the position of the point G be offset from the extension of the point O by the length (L4) of the arm P. Here, the point G does not have to be slid.

In the second embodiment and its modifications, as described in the first embodiment, the angular change detecting means is not limited to the gyro (sensor). For example, as is clear from FIG.
Two acceleration sensors 50A and 50B whose sensitivity axes (indicated by arrows pointing upward in the figure) are aligned in the same direction perpendicular to the arm N.
May be combined. In this case, the arm N is extended to the opposite side of the point G, and the acceleration sensors 50A, 50A
0B is fixed to the front / rear of point G, respectively.

In such a configuration, paying attention to the output difference between the two acceleration sensors 50A and 50B, there is no output difference when the arm N has no angular acceleration component with respect to the inertial system, and when there is an angular acceleration component, the output difference does not exist. Yes (acceleration component is applied in the opposite direction of one sensitivity axis). Therefore, the output difference between the two acceleration sensors 50A and 50B may be detected and drive control may be performed in a direction to suppress the output difference. Note that when an angular acceleration as indicated by a solid arrow a in the drawing occurs, accelerations as indicated by solid arrows a ′ and a ′ occur in the acceleration sensors 50A and 50B, and an angular acceleration as indicated by a broken arrow b. When acceleration is generated, acceleration is generated in each of the acceleration sensors 50A and 50B as indicated by broken-line arrows b 'and b'.

Regarding the mechanism of the above-described second embodiment, the entire length of the arm K may be relatively small (since the point A is a straight-line movement), and the correction optical system (which usually reaches a considerable weight) may be used. The moment of inertia around the point O of the correction lens 7) can also be kept small.

The moment of inertia of the correction optical system (correction lens 7) around point O is equivalent to the case where the correction optical system (correction lens 7) is located at point A 'in FIGS.

Since the distance between the point O and the point D is set to be much larger than the distance between the point A and the point B, the couple due to the own weight of the correction optical system (correction lens 7) around the point O is canceled. Of the Y driving unit balancer 39 can be made considerably smaller than the weight of the correction optical system (the correction lens 7 and the correction optical system frame 11). For example, in the examples shown in FIGS. 11 and 12, the distance between point A 'and point O is 2 and the distance between point O and point D is 10, so if the weight of the arm is ignored, the weight of the Y drive unit balancer 39 is corrected. Only 1/5 of the weight of the optical system (correction lens 7 and correction optical system frame 11) is required.

Here, this embodiment can also be driven in the Y direction and the X direction, and is provided with two balancers, so that the number of the balancers is two. However, the correction optical system (the correction lens 7 and the correction optical system frame 11) is still required. This is only 2/5 of the weight, which is excellent in portability, operability and the like.

As described above, the static balance of the center of the Y drive O-pin 36 of the mechanism member according to the present invention is obtained, and the drive characteristics of the mechanism are determined only by the inertia amount of the mechanism, and are not affected by gravity. For this reason, no matter what attitude,
The drive control characteristics of the present mechanism do not change, and highly accurate control is possible with a relatively simple circuit configuration. This means that in the control algorithm described with reference to FIG. 7, image blur correction with higher accuracy than in the first embodiment can be realized with a simple circuit.

Further, as described above, since the static balance of the mechanism is not dependent on the posture, the amount of force for holding the correction optical system (the correction lens 7 and the correction optical system frame 11) at a predetermined position is small. Since it is originally unnecessary (a slight holding force is needed to be able to counter the ultralow frequency angular velocity change component to which the drive control unit 23 does not respond), the Y drive worm wheel 40 is a spur gear, and the Y drive worm 41 is a pinion gear. Alternatively, a stepping motor having a stationary holding force (detent torque) may be used for the Y drive motor 42. Of course, roller driving, cam driving, and belt driving may be used.

FIGS. 15 to 17 show a third embodiment of the apparatus of the present invention. Here, FIG. 15 is a diagram viewed from the front in the optical axis direction, and FIG. 16 is a pitching direction (Y driving direction).
15 is a view of the driving mechanism 10 viewed from a direction perpendicular to the optical axis (obliquely upper left in FIG. 15), and shows a yawing direction (X driving direction).
The configuration is also substantially the same except that the motor faces the opposite side, and a specific illustration is omitted. FIG. 17 is a diagram further schematically illustrating only the pitching direction (Y driving direction).

The third embodiment is effective when the focal length f of the entire optical device fluctuates. Specifically, the third embodiment is effectively applied to a zoom lens and an inner focus type lens.

In the third embodiment, the correction optical system (correction lens 7), the correction optical system frame 11, the X stage 12, the fixed frame 13, and the correction optical system drive mechanism 10 in the first embodiment are used as the correction optical system drive mechanism 10. This is a combination of the arm K (Y drive shaft support member 33) and the arm N (Y detection arm 43) in the second embodiment described above.

The pitching gyro 18 is fixed to the arm N (Y detection arm 43).

Here, in this embodiment, a pin A (indicated by 60 in the figure) is set up at a point A on the arm K, and Y in the first embodiment is set.
Like the cylindrical projection 15a of the drive slider 15, the correction optical system frame 11 can be driven in the Y direction by rotation of the arm K around a point C (fixed point instead of slidable).

As shown in FIG. 16, the mechanism for rotating the arm K is such that the arm K (33) is extended to make the end face a worm wheel 40, which is rotated by a motor 42 with a worm 41. You may. Of course, the present invention is not limited to this, and a rotational force may be applied directly to the point C. Further, when the correction optical system is directly driven by a linear drive source such as a linear motor, the arm K (3
3) may be a driven member.

In this embodiment, the pin G at the point G is attached to the G pin slider 61 which can slide in the optical axis direction with respect to the apparatus housing. The G pin slider 61 extends to the pin G side of the X drive mechanism, and the pin G of the X drive mechanism is also attached. That is, the position of both pins G is determined by the front and rear positions of the G pin slider 61.

The pin G is slidably and rotatably fitted in the notch 43b of the arm N (43). The arm N (43) rotates with slight sliding about the pin G with the rotation of the arm K (33).
However, the rotation angle η of the arm N (43) and the arm K
If the rotation angle φ in (33) is small, the sliding amount is also small,
The point F point G distance is fixed to the point G and may be always regarded as L3. Normally, the stroke D '<< of the correction optical system (correction lens 7)
Since L1, this condition holds.

When the correction optical system (correction lens 7) is in a neutral state (a state in which the optical axis of the correction optical system coincides with the optical axes of the other optical systems), the points A, F, C, Point G is located on the same line, and arm K (33) and arm N (43) are parallel to the optical axis.

Here, when the focal length of the optical device (entire optical system) is variable, the right side of L1 × L3 / L2 = f / A changes in equation (10) shown above.
Change any one of L1, L2, and L3, and always change (1
What is necessary is just to make it satisfy | fill expression (0).

In this embodiment, the pin G can be slid in the optical axis direction of the apparatus by moving the G pin slider 61 with respect to the apparatus housing (lens barrel 4), and the entire optical apparatus (optical system) can be moved. The position is changed according to the change in the focal length. As such a configuration, for example, a zoom cam ring of a zoom lens, or a mechanism in which the G pin slider 61 is moved back and forth by a cam, a link, a screw mechanism, or the like in conjunction with the operation of a distance ring in the case of an in-focus lens is provided. I just need.

In the above configuration, for example, f = 30
0, A = 1 (constant), L1 = 8, L2 = 0.8,
If L3 = 30, the point G is 29.2 from the point C.
mm. If f = 200 due to zooming, L1 = 8 (Let A = 1), L2 =
Since 0.8 and L3 = 20, the point G may be a point 19.2 mm from the point C.

[0095] Even in the case of an inner focus type lens, the same adjustment as described above may be performed at the time of short-distance photography since the focal length becomes shorter than at the time of long-distance photography. Of course, even when the constant A changes, L1, L2, and L3 may be adjusted so as to satisfy the expression (10). In this example,
Although L3 is variable, it is obvious that L2 may be variable or L1 may be variable.

Further, the point G is slidably mounted on the apparatus housing and is slidably and rotatably fitted in the notch 43b of the arm N (43).
The G point connecting portion may be a rotatable connection, and the point F side may be a notch portion so as to be slidable.

Further, as shown in this example, L1, L2, L
FIGS. 8 to 1 show a mechanism for changing any one of FIGS.
It will be readily understood that the present invention may be applied to the second embodiment. For example, the Y drive unit support member 3 in the second embodiment
8 in the optical axis direction and the portion of the G pin 45
The format may be changed as in the embodiment.

As shown in FIG. 13 of the application of the second embodiment, the connecting portion between the arm K and the arm N at the point F is
Further, it may be performed through the added small arm P.

The image blur correction relating to yawing (X drive unit side) is exactly the same as in the first and second embodiments, and the control algorithm for drive control is also the same as that in FIG. It is needless to say that the explanation may be made or an appropriate control method may be used.

The present invention is not limited to the structure of the embodiment described above.
Needless to say, the structure and the like can be appropriately modified and changed, and various modifications can be considered. Needless to say, the devices and apparatuses to which the image blur correction optical device according to the present invention is applied are not limited to the still cameras in the above-described embodiments.

[0101]

As described above, the image blur correction optical apparatus according to the present invention is a correction device which constitutes a part of an optical system movably supported in a direction perpendicular to the optical axis for correcting image blur. An optical system, and driving means for driving the correction optical system,
A movable member configured to be operated by the drive unit and performing a motion with a rotational component when the drive unit is driven; an angular change detection unit fixed to the movable member and detecting rotation with respect to an inertial system; Control means for controlling driving of the drive means. The movable member is provided with an image blur amount d (d = f) at a change angle θ with respect to the optical axis of the optical system having an overall focal length of f. .Theta.), The amount of movement D'.DELTA.D '= D / A of the correction optical system (where A = coefficient, D
= Image moving amount)} in response to the angle change with respect to the optical system is movable so as to - [theta], the focal length of said movable member
By moving the movable member along the radius of curvature set based on the separation and the characteristic (A) of the correction optical system, the movable member corresponds to the movement of the movement amount D ′ of the correction optical system, and always moves with respect to the inertial system. There is provided an adjusting means which is configured not to rotate, or adjusts the amount of movement with respect to the driving amount of the movable member by the driving means of the correcting optical system. By rotating the movable member in accordance with the amount D 'so as to adjust the amount of movement of the movable member, various excellent effects listed below are exhibited despite the simple structure.

(1) Since a part of the means for driving the image blur correction optical system is not rotated with respect to the inertial system in accordance with the movement amount D 'of the correction optical system, it is mounted. By controlling the operation of the driving means by the control means in such a direction that the output of the angle change detection means becomes a static output (direction in which the angle change output disappears), appropriate image blur correction can be performed by the correction optical system. Further, as a result, there is an advantage that another means for monitoring the driving amount of the correction optical system becomes unnecessary.

(2) The setting of the angle change detecting means is also
It can be easily done because it is only fixed on one member.

(3) Even for an optical device such as a zoom lens or an inner focus type lens whose focal length changes depending on use conditions, it is not necessary to change the above control method only by devising a mechanism. In addition, the control circuit does not become complicated.

(4) Further, the control means for controlling the drive means for driving the correction optical system is controlled so as to operate the drive means so that the output of the angle change detection means approaches the stationary output, or to control the angle change. When the output of the detection unit is a stationary output, by controlling the driving unit to maintain the previous operation state, there is an advantage that the image blur due to the shaking can be appropriately corrected in accordance with the use condition. .

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram for explaining an outline of a suitable still camera to which an image blur correction optical device according to the present invention is applied.

FIG. 2 is a schematic front view showing an image blur correction optical system and a drive mechanism thereof according to a first embodiment of the image blur correction optical apparatus according to the present invention, as viewed from the optical axis direction.

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

FIG. 4 is a sectional view taken along line IV-IV of FIG. 2;

FIG. 5 is a sectional view taken along line VV of FIG. 2;

FIG. 6 is a schematic diagram for explaining a driving operation of the image blur correction optical system.

FIG. 7 is a flowchart illustrating an example of a drive control algorithm by a drive control unit in the image blur correction optical apparatus according to the present invention.

FIG. 8 is a schematic front view showing an image blur correction optical system and a drive mechanism thereof according to a second embodiment of the image blur correction optical apparatus according to the present invention, as viewed from the optical axis direction.

FIG. 9 is a schematic exploded perspective view of the Y drive unit in FIG. 8 as viewed from the side.

FIG. 10 is a cross-sectional view of a main part of the assembly of the mechanical components shown in FIG.

FIG. 11 is a schematic diagram illustrating a main configuration of an image blur correction optical apparatus according to the present invention in relation to a still camera.

FIG. 12 is a schematic diagram of an image blur correction optical device showing an enlarged main part of FIG. 11;

FIG. 13 is a schematic diagram showing a modification of the schematic diagram of the image blur correction optical device shown in FIG. 12;

FIG. 14 is a schematic diagram showing another modification of the device schematic diagrams of FIGS. 12 and 13;

FIG. 15 is a schematic front view showing an image blur correction optical system and a drive mechanism thereof according to a third embodiment of the image blur correction optical apparatus according to the present invention, as viewed from the optical axis direction.

FIG. 16 is a schematic exploded perspective view of the image blur correction optical device shown in FIG. 15 as viewed from a direction perpendicular to the optical axis.

FIG. 17 is a schematic diagram showing a configuration of a main part of an apparatus in the third embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Telephoto lens with image blur prevention function, 2 ... Still camera, 4 ... Lens barrel, 7 ... Image blur correction lens (image blur correction optical system), 8 ... Film, 10 ... Image blur correction optical system drive mechanism , 11: correction optical system frame, 12: X stage, 1
3 ... fixed frame, 15 ... Y drive slider, 15a ... cylindrical projection, 16 ... Y drive pinion gear, 17 ... Y drive motor, 18 ... pitching angular velocity meter (sensor), 19 ... X drive slider, 20 ... X drive Pinion gear, 21 ... X drive motor, 22 ... Yawing angular velocity meter, 23 ... Drive control unit, 30 ... X drive unit, 31 ... Y drive unit, 32 ... Cylinder Y
Drive shaft (columnar X drive shaft), 33 ... Y drive shaft support member (X drive shaft support member), 34 ... Y drive B pin (X drive B pin), 35 ... Y drive arm (X drive arm) , 3
6 ... Y drive O pin (X drive O pin), 37 ... Y drive C pin (X drive C pin), 38 ... Y drive section support member (X drive section support member), 39 ... Y drive section Balancer (X drive balancer), 40 ... Y drive worm wheel (X drive worm wheel), 41 ... Y drive worm (X drive worm), 42 ... Y drive motor (X drive motor), 4
3 ... Y detection arm (X detection arm), 44 ... F pin, 45 ... G pin, 46 ... Y drive bearing part, 47 ... X drive bearing part, 50A ... Acceleration sensor (angle change detection means), 50B ... Acceleration sensor (angle change detecting means), 60
... Pin A, 61 ... G pin slider.

Claims (4)

(57) [Claims] 1. A correction optical system constituting a part of an optical system movably supported in a direction perpendicular to an optical axis for correcting image blur, a driving unit for driving the correction optical system, A movable member configured to be operated by the driving unit and performing a motion accompanied by a rotational component when the driving unit is driven; an angular change detection unit fixed to the movable member and detecting rotation with respect to an inertial system; Control means for controlling driving of the driving means. The movable member is provided with an image blur amount d (d = f.multidot.d) at a change angle .theta. θ)
D '補正 D' = D /
A (where A = coefficient, D = image movement amount) 移動
By moving the movable member along the radius of curvature set based on the focal length and the characteristic (A) of the correction optical system, the movable member is moved so that the angle change with respect to the optical system becomes −θ. , The movement amount D ′ of the correction optical system
An image stabilization optical apparatus characterized in that the apparatus is configured not to rotate with respect to the inertial system at all times in response to the movement of the image. 2. The image blur correction optical apparatus according to claim 1, further comprising: an adjusting unit that adjusts the amount of movement of the movable optical member with respect to the amount of driving of the movable member by the driving unit of the correcting optical system. Movement amount D ′ ｛D ′ = D / A of the correction optical system for correcting the image shake amount d (d = f · θ) at the change angle θ with respect to the optical axis of the optical system whose distance is f.
(Where A = coefficient, D = amount of image movement)｝, and the amount of movement of the movable member is adjustable so that the angle change with respect to the optical system becomes −θ. Optical device. 3. The image blur correction optical device according to claim 1, wherein the control means for controlling the driving means for driving the correction optical system includes: an output of the angle change detection means approaching a stationary output. An image blur correction optical apparatus, wherein the apparatus is controlled to operate a driving unit. 4. The image blur correction optical device according to claim 1, wherein the control means for controlling the driving means for driving the correction optical system comprises a stationary output as the output of the angle change detecting means. An image stabilization optical apparatus characterized in that it is controlled so as to maintain the previous operation state of the driving means.