JPH07301769A - Supporting mechanism for optical axis correcting lens - Google Patents

Abstract

PURPOSE:To realize eccentricity of an optical axis correcting lens against the main lens system in almost the same plane without moving the eccentricity in an optical axis direction in a supporting mechanism for the optical axis correcting lens suitable for an optical system equipment requiring the correction of camera shake, and to accurately correct an optical axis. CONSTITUTION:As for a leaf spring 9 supporting a convex lens 8 for correction in a direction orthogonally crossed with the optical axis; 1st vertical spring pieces 13 and 13 and 2nd vertical spring pieces 16 and 16 are formed to be extended in an opposite direction to each other with a coupling piece 15 as a folding part, and the lens 8 is supported at the ends of the spring pieces 13 and 13 on an anti-coupling piece side and the ends of the spring pieces 16 and 16 on the anti-coupling piece side are supported in a lens barrel.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel optical axis correcting lens support mechanism. Specifically, for example, regarding a supporting mechanism of an optical axis correcting lens suitable for an optical system device such as a handy type video camera device or a telescope that requires so-called camera shake correction in a use state, the main axis of the optical axis correcting lens is An object of the present invention is to provide a novel optical axis correcting lens support mechanism capable of performing decentering with respect to a lens system within a substantially one plane and performing optical axis correction with high accuracy.

[0002]

2. Description of the Related Art For example, in a handy type video camera device, as a method for correcting the camera shake, an afocal lens composed of a convex lens and a concave lens is arranged in front of a taking lens system as an optical axis correcting lens, and these convex lenses are used. And / or a method of correcting a camera shake by moving a concave lens in a direction orthogonal to the optical axis is known.

In such a system, in order to move the optical axis correcting lens in a direction orthogonal to the optical axis, it is necessary to support the optical axis correcting lens by, for example, a leaf spring suspension.

FIGS. 10 and 11 explain a method of correcting a camera shake by moving an afocal lens composed of a convex lens and a concave lens as an optical axis correcting lens, and moving the convex lens of these lenses in a direction orthogonal to the optical axis. It is a schematic diagram for doing.

Although FIG. 10 shows an optical axis correcting lens movably supported in the vertical direction, it is actually movable also in the horizontal direction. Is movable in the range of 360 degrees around the optical axis when viewed from the optical axis direction.

Reference numeral a denotes a taking lens system, and an image pickup device (CCD) b is arranged behind it.

Reference numeral c denotes a correcting convex lens located on the side of the taking lens system a of the optical axis correcting lens composed of an afocal lens, and the correcting convex lens c is close to the front side of the taking lens system a. Are arranged via suspensions d and d, and the optical axis x ′ thereof is always parallel to the main optical axis x of the photographing lens system a.

Specifically, the two suspensions d, d
Are made of a leaf spring material and have the same shape.

Further, the suspensions d, d have one end supporting a lens holder (not shown) holding a correcting convex lens c, and the other end being supported on the outer peripheral surface of the lens barrel e of the taking lens system a. Therefore, the optical axes x and x ′ and the suspensions d and d are substantially parallel to each other in a state where the optical axis x of the photographing lens system a and the optical axis x ′ of the correction convex lens c are aligned. There is.

Reference numeral f denotes a linear motor for driving the correcting convex lens c, which includes a yoke g attached to the lens housing side (not shown), a magnet h attached to the yoke g, and a correcting convex lens c side. It consists of a moving coil i and the like that are worn. Although only the linear motor f in the vertical direction is shown in FIG. 10, a linear motor in the horizontal direction is actually provided.

Reference numeral j is a position sensor for detecting the position of the correcting convex lens c, and is, for example, an issuing diode (LE).
D) k and a semiconductor position detector (PSD) 1 etc.,
The PSDl is formed in a rectangular shape whose light receiving surface is long in one direction. Although only the position sensor j in the vertical direction is shown in FIG. 10, a position sensor in the horizontal direction is actually provided.

The LEDk is attached to the peripheral portion of the correcting convex lens c at a position which is 90 degrees apart at the central angle in the circumferential direction from the position where the linear motor f is arranged.

PSDl is the above L of the lens housing (not shown).
It is attached at a position facing EDk, and its direction is such that its longitudinal direction extends in substantially the same direction as the tangential direction of the correcting convex lens c.

The position component in the vertical direction of the correcting convex lens c is located at a position facing a horizontal linear motor (not shown) with the optical axis x'in-between.
Further, the horizontal position component of the correction convex lens c is arranged by a position sensor (not shown) arranged at a position opposed to the vertical linear motor f with the optical axis x therebetween.
Each is detected.

Reference numeral m denotes a camera shake detection sensor composed of an angular velocity sensor. When a camera shake is detected, a camera shake detection signal is output. The camera shake detection signal is angular velocity data. The change in angle is detected.

The angle data detected by the camera shake amount calculation circuit n is compared with the position data of the optical axis correction lens c obtained by the position sensor j or the like in the optical axis correction lens position control circuit o and corrected. The amount of the angle to be detected is detected, the correction data is output to the linear motor f, etc., and the optical axis correcting lens c is moved in the vertical direction or the horizontal direction to correct the optical axis. Has become.

[0017]

However, in such an optical axis correcting lens supporting mechanism, when the correcting convex lens c is moved, the two suspensions d and d are formed.
Have the same structure, the correcting convex lens c moves while its optical axis x ′ is kept parallel to the optical axis x of the taking lens system a, but the movement is an arc motion and the correcting convex lens c Is displaced with respect to the taking lens system a, as shown in FIG.
As shown in FIG. 1, “deviation L” occurs in the optical axis direction.

The "deviation L" in the optical axis direction of the correcting convex lens c causes the image forming position to be displaced backward, and CCDb should be imaged on the CCDb surface even though it should originally be imaged. There is a problem that an image cannot be formed on the surface and defocus occurs.

The problem is that C
The depth of field of a CD tends to be small, and the "deviation L" to the rear of the optical axis correcting lens has been a serious problem.

[0020]

In order to solve the above-mentioned problems, the optical axis correcting lens support mechanism of the present invention has one end supporting the optical axis correcting lens and the other end being a fixed member. The folded portion is formed in the supported suspension.

[0021]

Therefore, according to the supporting mechanism of the optical axis correcting lens of the present invention, since the folded portion is formed in the suspension,
Since the lens supporting point and the supported point of the suspension are close to each other and the supported point is fixed, the folded-back portion is covered by the movement of the optical axis correcting lens in the direction orthogonal to the optical axis. The lens supporting point moves forward with respect to the supporting point, and the lens supporting point moves rearward with respect to the folded portion, and the forward movement of these folded portions and the backward movement of the lens supporting point mutually interact. As a whole, the movements of the optical axis correcting lens in the optical axis direction can be almost eliminated or reduced, the above-mentioned defocusing at the time of optical axis correction can be prevented, and the CCD can be miniaturized. Can also be adapted.

[0022]

1 is a principle view for explaining the principle of a suspension in a supporting mechanism for an optical axis correcting lens according to the present invention.

Reference numeral 1 denotes a suspension in which a folded-back portion 2 bent in a V shape is formed at an intermediate portion in the lengthwise direction. Both ends of the suspension 1 are close to each other, and a lens 3 is supported at one end thereof. Further, the other end is fixed to a fixed member (not shown) (for example, a lens barrel), so that the lens 3 is movable in a direction orthogonal to the optical axis.

When the lens 3 is moved in a direction orthogonal to the optical axis, for example, in the upward direction, the suspension 1
Supported point 1a and folded-back portion 2 supported by the fixed side member
The portion between the and (hereinafter, referred to as "deviation suppressing spring piece") 4
Further, a portion 5 between the lens supporting point 1b and the folded portion 2 (hereinafter, referred to as "deviation generating spring piece") 5 is bent as indicated by a chain double-dashed line in FIG.

At this time, the displacement generating spring piece 5 is bent with the folded-back portion 2 as a fulcrum, and the lens support point 1b is relatively moved rearward in relation to the folded-back portion 2 and the displacement-generating spring 5 is moved. The bending of the piece 5 causes the lens support point 1b to shift rearward in the optical axis direction, that is, causes a "deviation" in the optical axis direction, which is a problem to be solved by the present invention.

On the other hand, the displacement suppressing spring piece 4 is bent around the supported point 1a as a fulcrum, and the supported point 1a is fixed. Therefore, the folded portion 2 is moved forward, and the displacement suppressing spring is moved. The bending of the piece 4 causes the folded-back portion 2 to move forward, that is, to move in the direction of canceling the “misalignment” of the above problem, and the lens support point 1b as a whole moves forward and backward. The rearward movement of the lens support point 1b is offset.

As a result, the lens 3 moves on one plane orthogonal to the optical axis with almost no movement in the optical axis direction.

An example of an embodiment in which the details of the supporting mechanism of the optical axis correcting lens of the present invention is applied to a video camera device will be described below with reference to FIGS. 2 to 9.

In the figure, reference numeral 6 is a support mechanism for the optical axis correcting lens, and among the optical axis correcting lenses constituted by afocal lenses, the correcting convex lens 8 located on the side of the photographing lens system 7 and the correcting convex lens. Drive means for moving the leaf springs 9, 9 and the correcting convex lens 8 to predetermined positions so that the optical axis X ′ of the taking lens system 7 can be moved while keeping the optical axis X ′ in parallel with the main optical axis X of the taking lens system 7. 10 and 10 and position detecting means 11 and 11 for detecting the positions of the correcting convex lens 8 are provided.

The correcting convex lens 8 is supported by the lens holder 12 and is positioned in front of the taking lens system 7, and
The optical axis X'is positioned so as to be parallel to the main optical axis X of the taking lens system 7.

Since the driving means 10 and 10 and the position detecting means 11 and 11 have substantially the same structure as that shown in the conventional example, detailed description thereof will be omitted.

The lens holder 12 has a substantially ring shape. A coil bobbin is integrally provided on the upper end portion and the right end portion of the lens holder 12 so as to project outward, and a position sensor described later is provided on the lower end portion and the left end portion thereof. A mounting piece for mounting the LED is integrally projecting outward.

The leaf spring 9 is composed of two first vertical spring pieces 13 and 13 which are long and horizontal in the front-rear direction and are vertically spaced apart from each other, and one of the first vertical spring pieces 13 and 13. Vertically supported piece 1 that connects the front ends of the side edges of the
4 and the first non-supported piece 1 of each vertical spring piece 13, 13.
A vertically oriented connecting piece 15 connecting between the rear end portions of the four sides,
Two second longitudinally-horizontal orientations which are vertically spaced apart from each other above and below the first vertical spring pieces 13, 13 and whose rear ends are connected to the connecting piece 15 respectively. The vertical spring pieces 16 and 16 and the support pieces 17 in the vertical direction connecting the front end portions of the second vertical spring pieces 16 and 16.

The leaf spring 9 thus formed corresponds to the suspension 1 explained in the above explanation of the principle, the first vertical spring pieces 13 and 13 correspond to the deviation suppressing spring piece 4 in the explanation of the principle, and the second one. The vertical spring pieces 16, 16 correspond to the displacement generating spring piece 5 in the explanation of the principle, and the connecting portion 1
5 corresponds to the folded portion 2.

Further, the supported piece 14, the connecting piece 15 and the supporting piece 17 have rectangular holes 14a, 15a, 17 elongated in the vertical direction.
a are formed respectively, so that the rectangular holes 14a, 15 of the supported piece 14, the connecting piece 15, and the supporting piece 17 are formed.
a, 17a, a first horizontal spring piece 18, 18 having a narrow width in a vertical direction on both upper and lower sides, and a second horizontal spring piece 19, 19,
Third horizontal spring pieces 20, 20 are formed respectively.

The leaf spring 9 shown in FIG. 3 is the lens barrel 2
1 is arranged on the left side of 1.

13a, 13a, ..., 16a, 16a
Is a first vertical spring piece 13 and a second vertical spring piece 16
Is a rectangular small hole for adjusting the spring constant and is arranged in a large number in the longitudinal direction of each vertical spring piece 13, 16, and the size and the number of small holes 13a and 16a are the same. The spring constants of the vertical spring pieces 13 and 16 are determined to be predetermined values.

The leaf spring 9 is formed by punching and bending a leaf spring material having a predetermined size.

Then, the leaf spring 9 thus formed,
Reference numeral 9 indicates a state in which the supported pieces 14, 14 are oriented in a direction perpendicular to the left and right side surfaces of the lens barrel 21 of the photographing lens system 7, and the supporting pieces 17, 17 project forward of the photographing lens system 7. Then, it is fixed to the lens barrel 21 with screws or the like.
The member for supporting the leaf spring 9 is not limited to the lens barrel 21, but may be any member on the fixed side, and may be, for example, the housing of a video camera.

Specifically, the portion of the leaf spring 9 located behind the rectangular hole 14a of the supported piece 14 is fixed to the lens barrel 21 with a screw.

The left and right ends of the lens holder 12 are supported between the tip ends of the support pieces 17, 17 of the leaf springs 9, 9 by a screw or the like in a predetermined direction, and the leaf pieces 13 of the leaf springs 9, 9 are supported. , 13, ..., 16, 16, ..., 18, 1,
8, ..., 19, 19, ..., 20, 20, ...
Is not bent, the optical axis X of the correction convex lens 8 is
′ Coincides with the main optical axis X of the taking lens system 7.

Specifically, the left and right side edges of the lens holder 12 are screwed to the portion of the support piece 17 of the leaf spring 9 located on the front side of the rectangular hole 17a so that the supported piece 14 and the support piece 17 are close to each other. Is arranged in a position.

Thus, the length between the supported piece 14 and the connecting piece 15, that is, the length of the first vertical spring piece 13 and the length between the connecting piece 15 and the supporting piece 17, that is, the first The length of the second vertical spring piece 16 is substantially the same.

Therefore, the correcting convex lens 8 is the driving means 1
By 0, for example, when the leaf spring 9 is moved upward, the leaf spring 9 bends as follows (see FIGS. 6 and 7).

That is, when the correcting convex lens 8 moves upward, the second vertical spring pieces 16 and 16 are bent so that the supporting piece 17 side thereof is displaced upward, and this bending is the connecting piece 15.
Is the base end, and therefore the correction convex lens 8 is relatively displaced rearward in relation to the connecting piece 15.

On the other hand, since the first vertical spring pieces 13 and 13 are curved so that the connecting piece 15 side is displaced upward with the supported piece 14 as the base end, this bending causes the connecting piece 15 and the supported piece 14 to move. Because of this, there will be a relative shift to the front.

As a result, the second vertical spring pieces 16, 1
The backward movement of the support piece 17 due to the bending of No. 6 and the forward movement of the connecting piece 15 due to the bending of the first vertical spring pieces 13 and 13 are offset, and the correction convex lens 8 is moved upward. The object does not substantially move in the optical axis direction, but moves on one plane orthogonal to the optical axis.

Strictly speaking, the second vertical spring pieces 16, 1 are used.
Since the length of 6 in the optical axis direction is slightly longer than that of the first vertical spring pieces 13 and 13, when the correcting convex lens 8 moves upward, it is moved slightly backward. However, unlike the conventional example having no folded portion, there is no extreme "deviation" to the rear, and no blurring occurs during optical axis correction.

Preferably, as described in the above description of the principle, the first vertical spring piece 13 (deviation suppressing spring piece 4) and the second vertical spring piece 16 (deviation occurrence) of the leaf spring 9 (suspension 2). It is preferable that the spring piece 5) has the same length.

When the correcting convex lens 8 is moved to the right, for example, by the driving means 10, the leaf spring 9 bends as follows (see FIGS. 8 and 9).

That is, when the correcting convex lens 8 moves to the right, the first horizontal spring pieces 18, 18, the second horizontal spring pieces 19, 19 and the third horizontal spring pieces 20, 20 are moved to the position shown in FIG. Bend as shown in. And these horizontal spring pieces 1
The "deviation" in the direction of the optical axis due to 8, 19, 20 itself can be almost ignored because the angle of bending is small and the length thereof is short, but the vertical spring pieces 13, 16 extending in the tangential direction of these can be ignored. Due to the long length, these must be taken into consideration.

In this case, the first vertical spring piece 13 serves as the displacement suppressing spring piece 4, and the second vertical spring piece 16 serves as the vertical spring piece 16.
Corresponds to the displacement generating spring piece 5, and the connecting piece 15 corresponds to the folded-back portion 2.

Therefore, when the correcting convex lens 8 moves to the right, the second vertical spring piece 16 inclines with the connecting piece 15 as the base end, so that the correcting convex lens 8 moves relative to the connecting piece 15. It will shift backwards.

On the other hand, since the first vertical spring piece 13 is inclined with the supported piece 14 as the base end, the connecting piece 15 is relatively displaced forward in relation to the supported piece 14.

As a result, the backward movement of the support piece 17 due to the inclination of the second vertical spring piece 16 and the forward movement of the connecting piece 15 due to the inclination of the first vertical spring piece 13 are offset, Although the correction convex lens 8 is moved to the right, it does not substantially move in the optical axis direction, and moves on one plane orthogonal to the optical axis.

In the above embodiment, the number of folding portions is one, but the present invention is not limited to this, and a plurality of folding portions may be provided. In such a case, in order to bring the lens-side supporting point and the fixed-side supporting point of the suspension close to each other, it is preferable that the number of folded portions is an odd number.

[0057]

As is apparent from what has been described above, according to the optical axis correcting lens supporting mechanism of the present invention, the eccentricity is provided in a substantially plane that is arranged in front of the main lens system and is orthogonal to the optical axis. A support mechanism for an optical axis correction lens, comprising: an optical axis correction lens that is movably supported; and a suspension, one end of which supports the optical axis correction lens and the other end of which is supported by a fixed-side member. The folded portion is formed in the suspension.

Therefore, according to the supporting mechanism of the optical axis correcting lens of the present invention, since the folded portion is formed in the suspension, the lens supporting point and the supported point of the suspension are brought close to each other and the supported point is fixed. Therefore, as the lens for optical axis correction moves in the direction orthogonal to the optical axis,
The folding part moves forward with respect to the supported point, and the lens supporting point moves rearward with respect to the folding part, so that the folding part moves forward and the lens supporting point moves backward. Cancel each other out, and as a whole, the movement of the optical axis correcting lens in the optical axis direction can be substantially eliminated or reduced, and the defocusing at the time of optical axis correction can be prevented. It can also be applied to miniaturization.

In the above embodiment, the leaf springs having the two spring pieces which are individually bent in the two directions orthogonal to each other are arranged on the left and right sides of the lens barrel. However, the support mechanism for the optical axis correcting lens of the present invention is not limited to this, and the suspension may be a so-called wire having a thin round bar shape.
Any suspension may be used as long as it is a suspension that supports the optical axis correcting lens so that it can be decentered in a substantially plane orthogonal to the optical axis.

Further, in the above-mentioned embodiment, the case where the present invention is applied to the video camera device has been described. However, the supporting mechanism of the optical axis correcting lens of the present invention is not limited to this, and the shake correction of a telescope, a laser pointer or the like can be performed. It can be applied to optical equipment that must be.

In addition, the structures and shapes of the respective parts shown in the above embodiments are merely examples of the embodiment when the present invention is carried out, and the technical scope of the present invention is limited by these. Should not be interpreted as.

[Brief description of drawings]

FIG. 1 is a schematic diagram for explaining the principle of a support mechanism of an optical axis correcting lens of the present invention.

FIG. 2 shows an example of an embodiment of a support mechanism for an optical axis correcting lens of the present invention, together with FIGS. 3 to 9, and this figure is a perspective view of a main part.

FIG. 3 is a perspective view showing a suspension.

FIG. 4 is a side view showing the entire structure with a part cut away.

FIG. 5 is a front view showing the overall configuration.

FIG. 6 is a side view showing the suspension in a state where the optical axis correcting lens is not decentered.

7 is a side view showing a state where the optical axis correcting lens is eccentric upward from the state of FIG.

FIG. 8 is a plan view showing the suspension in a state where the optical axis correcting lens is not decentered.

9 is a plan view showing a state where the optical axis correcting lens is decentered to the right from the state of FIG.

FIG. 10 is a schematic view showing an example of a conventional optical axis correcting lens support mechanism.

FIG. 11 is a schematic diagram for explaining a problem of a conventional support mechanism for an optical axis correcting lens.

[Explanation of symbols]

 X Optical axis of main lens system 1 Suspension 1a Supported point (fixed side supporting point) 1b Lens supporting point (lens side supporting point) 2 Folding part 3 Lens (optical axis correcting lens) 6 Optical axis correcting lens supporting mechanism 7 Shooting lens system (main lens system) 8 Correcting convex lens (optical axis correcting lens) 9 Leaf spring (suspension) 14 Supported piece (fixed side supporting point) 15 Connecting piece (folding part) 17 Supporting piece (lens side supporting) 21) Lens barrel (fixed side member)

Claims (3)

[Claims] 1. An optical axis correcting lens which is disposed in front of a main lens system and is eccentrically supported in a substantially plane orthogonal to the optical axis, and one end supports the optical axis correcting lens and the other end. A support mechanism for an optical axis correction lens, comprising: a suspension supported by a fixed member; wherein a folding portion is formed on the suspension. 2. The optical axis correcting lens support mechanism according to claim 1, wherein the lens side support point and the fixed side support point of the suspension are located close to each other in the optical axis direction. 3. The support mechanism for an optical axis correcting lens according to claim 1, wherein the number of folded-back portions of the suspension is an odd number.