JP3355745B2 - Driving mechanism of optical axis correction lens - Google Patents

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 driving mechanism. Specifically, for example, regarding a driving mechanism of an optical axis correction lens suitable for an optical system device that requires so-called camera shake correction in use such as a handy type video camera device or a telescope, the power consumption during driving is reduced. It is an object of the present invention to provide a novel optical axis correcting lens driving mechanism that can be driven.

[0002]

2. Description of the Related Art For example, in a handy type video camera apparatus, as a method for correcting camera shake, an afocal lens formed by combining two lenses in front of a taking lens system is disposed as an optical axis correcting lens. By moving each lens separately in two directions perpendicular to the axis and perpendicular to each other (usually vertical direction and horizontal direction), or by moving only one lens in a plane direction perpendicular to the optical axis. There is a method for correcting camera shake.

Such an afocal lens is usually constituted by combining four curved surfaces, two concave curved surfaces and two convex curved surfaces. For example, a lens composed of a concave surface and a convex surface (hereinafter, referred to as an "irregular lens"). A combination of a lens composed of a convex surface and a concave surface (hereinafter, referred to as a "convex-convex lens"), a lens composed of a concave surface and a concave surface (hereinafter, a "concave concave lens"), and a lens composed of a convex surface and a convex surface (hereinafter, a "convex-convex lens") ) Is conceivable.

[0004]

FIG. 8 shows an afocal lens c having a convex-concave lens a on the front side and a concave-convex lens b on the rear side.

FIG. 9 shows an afocal lens d having a concave-convex lens b on the front side and a concave-convex lens a on the rear side.

FIG. 10 shows an afocal lens e having a concave-convex lens b on the front side and a concave-convex lens b on the rear side.

FIG. 11 shows an afocal lens f in which a convex-concave lens a is arranged on the front side and a convex-concave lens a is arranged on the rear side.

However, since the convex and concave lenses a and b used for such afocal lenses c, d, e, and f are not plane-symmetrical in a plane perpendicular to the optical axis, it is difficult to form them. There is. Furthermore, the afocal lenses c and d shown in FIGS. 8 and 9 have a problem that the size in the optical axis direction is large, which is against the miniaturization.

Therefore, as shown in FIG. 12, an afocal lens i having a convex-convex lens g on the front side and a concave-concave lens h on the rear side is conceivable.

In such an afocal lens i, a concave / concave lens h provided on the rear side is movably supported by suspensions j and j in a plane direction orthogonal to the optical axis, and is driven by a driving mechanism k. It can be moved to a predetermined position.

However, since the concave-convex lens h is formed to have a thin center portion and a thick peripheral portion, the weight is increased,
The drive power of the drive mechanism k for moving this must be increased, and there is a problem that power consumption is increased.

[0012]

In order to solve the above-mentioned problem, the driving mechanism of the optical axis correcting lens according to the present invention comprises two lenses , a convex lens and a concave lens.
The lens for optical axis correction placed in front of the lens system and the optical axis
Perpendicular to the horizontal direction and perpendicular to each other
Suspensions supported separately for movement in two directions,
The optical axis correcting lens is moved separately in two orthogonal directions.
And a drive means for adjusting the optical axis.
Lens always moves with respect to the main optical axis of the main lens system.
It is supported so as to be parallel, and the driving means
The position is moved in parallel with the optical axis .

[0013]

Therefore, according to the optical axis correcting lens driving mechanism of the present invention, the movable lens of the afocal lens is convex.
Since it is a lens , concave with the same aperture and the same refractive index
The volume can be reduced as compared with the lens , and therefore, the weight can be reduced, so that the driving power for driving the lens can be reduced. In addition, external
When subjected to velocity, the held convex lens will have its mass
It works to remain at the position before receiving acceleration due to inertia.
Therefore, the driving force of the driving mechanism for driving the target correction amount is reduced.
You can also save.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the driving mechanism of the optical axis correcting lens of the present invention will be described below with reference to an embodiment applied to a video camera apparatus.

[0015] In addition, "h" added to the reference numeral of each member described later.
Alternatively, the suffix “v” indicates that “h” indicates that it is related to the horizontal (H) direction, and “v” indicates that it is related to the vertical (V) direction.

Reference numeral 1 denotes a driving mechanism of an optical axis correcting lens,
A concave-concave lens 3 and a convex-convex lens 4 constituting the afocal lens 2, and a suspension 6 movably supporting the convex-convex lens 4 while keeping an optical axis X ′ thereof parallel to the main optical axis X of the photographing lens system 5; 6 and a driving means 7 for moving the convex-convex lens 4 to a predetermined position.

The concave-convex lens 3 is attached to the front end of the lens barrel 8, and its optical axis coincides with the main optical axis X of the taking lens system 5.

The convex-convex lens 4 is supported by a lens holder 9 and is located between the concave-concave lens 3 and the taking lens system 5, and its optical axis X ′ is parallel to the main optical axis X of the taking lens system 5. Is located as

In this embodiment, since the convex-convex lens 4 is located behind the concave-concave lens 3, the front of the convex-convex lens 4 is protected by the concave-concave lens 3, and a dedicated protective lens is provided in front of the movable lens. Need not be provided, which can contribute to the overall weight reduction.

The lens holder 9 is substantially ring-shaped, and has coil bobbins 10h, 1h at its upper end and right end.
0v is integrally protruded outward.

The coil bobbin 10 is composed of two parallel bobbin pieces 10a and 10a.
The center of the space between a and 10a coincides with the radial direction about the axis of the lens holder 9.

The suspension 6 includes two vertical spring pieces 11, 11 which are long and horizontal in the front-rear direction and are vertically separated from each other, and a front end of one side edge of each vertical spring piece 11, 11. And a vertically oriented support piece 12 connecting
The vertical spring pieces 11 and 11 each have a vertically-oriented supported piece 13 that is connected between the rear end portions of the vertical spring pieces 11 and 11 on the side opposite to the support piece 12. Longer rectangular holes 12a and 13a are formed at the positions closer to the vertical, respectively, so that the support piece 12 and the supported piece 13 are closer to the vertical spring pieces 11 and 11 and are perpendicular to the upper and lower edges. Orientation-oriented horizontal spring pieces 14, 14, ...
.. is formed.

The suspension 6 is formed by punching and bending a sheet metal material having a predetermined size.

The suspensions 6 and 6 thus formed have their supported pieces 13 and 13 oriented perpendicular to the left and right sides of the photographic lens barrel 15 of the photographic lens system 5, and the support pieces 12. , 12 protrude forward from the taking lens system 5 and are fixed by screws or the like.

The left and right ends of the lens holder 9 have a predetermined orientation (the coil bobbin 10 at the upper end extends upward, and the coil bobbin 10 at the right end extends rightward between the tips of the support pieces 12, 12 of the suspensions 6, 6). Orientation) and supported by screws or the like.
In a state where 1, 11,..., 14, 14,.
Of the main optical axis X.

The driving means 7 includes a moving coil 16 wound around the bobbin pieces 10a and 10a of the coil bobbin 10 of the lens holder 9 and a section E fixed to the main body (not shown).
The yoke 17 includes a yoke 17 and magnets 18 attached to the yoke 17.

The yoke 17 has a middle piece 17a formed sufficiently smaller than a space between the bobbin pieces 10a of the coil bobbin 10, and a middle piece 17a formed between the bobbin pieces 10a and 10a. Is placed at a position where it is inserted from the outside into the space of
The magnets 18, 18 are attached to 7b, 17b.

Then, by supplying power to the moving coil 16, the lens holder 9 moves in the above-mentioned radial direction.

The driving means 7h and 7v are disposed at the upper end and the right end of the lens holder 9, respectively, whereby the driving means 7v disposed at the upper end are provided.
, The convex-convex lens 4 can be moved in the vertical direction, and the convex-convex lens 4 can be moved in the horizontal direction by driving the driving means 7h disposed at the right end.

Although not shown, the lens holder 9 is not shown.
Is provided with a position sensor for separately detecting position components in the H direction and the V direction, and a camera shake detection sensor comprising an angular velocity sensor is attached to the lens barrel side. The camera shake detection sensor detects camera shake. Upon detection, a shake detection signal is output. Since the shake detection signal is angular velocity data, the shake detection signal is integrated by a camera shake calculation circuit to detect a change in angle.

The angle data detected by the camera shake amount calculation circuit is compared with the position data of the convex-convex lens 4 obtained by the position sensor by the optical axis correction lens position control circuit, and the amount of the angle to be corrected is determined. The detected correction data is output to the driving means 7h and 7v, and the convex-convex lens 4
In the direction and / or the V direction, the optical axis is corrected.

When the convex / convex lens 4 is moved in the H direction and / or the V direction by the driving means 7h and 7v, again.
The position of the convex-convex lens 4 is detected by the position sensor,
Position closed loop servo control is performed so that this position data matches the target value.

[0033]

As is apparent from the above description, the driving mechanism of the optical axis correcting lens according to the present invention includes a convex lens and a convex lens.
Consists of two lenses, a concave lens and in front of the main lens system
The optical axis correction lens placed and the direction perpendicular to the optical axis
Moving in two directions perpendicular to the horizontal direction and perpendicular to each other.
Suspensions supported separately for each and the above optical axis correction
Driving means for moving the lens separately in two directions orthogonal to each other;
The suspension is a convex lens of the optical axis correction lens.
Lens should always be parallel to the main optical axis of the main lens system.
And the driving means moves the convex lens to a predetermined position with respect to the optical axis.
And moved in parallel .

Therefore, according to the optical axis correcting lens driving mechanism of the present invention, since the movable lens of the afocal lens is a convex lens , the volume is smaller than that of a concave lens having the same aperture and the same refractive index. Therefore, the weight can be reduced, so that the driving power for driving it can be reduced. Also, from outside
When subjected to acceleration, the held convex lens has its mass
To remain in the position before receiving acceleration due to inertia
Good. Therefore, the drive of the drive mechanism that drives the target correction amount
You can also save power.

In the above embodiment, the case where the convex and convex lenses are positioned between the concave and convex lenses and the main lens system has been described. However, the present invention is not limited to this, and the convex and convex lenses are positioned in front of the concave and convex lenses. Thus, it may be supported so as to be movable in a plane direction orthogonal to the optical axis.

Further, the structures and shapes of the respective parts shown in the above-described embodiments are only examples of the embodiment of the present invention, and the technical scope of the present invention is limited. Should not be interpreted.

[Brief description of the drawings]

FIG. 1 shows an embodiment of a driving mechanism of an optical axis correcting lens according to the present invention together with FIGS. 2 to 7, and is an exploded perspective view of a main part.

2 shows a state in which the optical axis of the optical axis correcting lens coincides with the optical axis of the main lens system together with FIG. 3, and FIG. .

FIG. 3 is a cross-sectional view of a main part.

FIG. 4 shows a state in which the optical axis correcting lens has been moved upward together with FIG. 5, and FIG. 4 is a longitudinal sectional view of a main part shown with a part cut away.

FIG. 5 is a cross-sectional view of a main part.

FIG. 6 shows a state in which the optical axis correcting lens has been moved to the left along with FIG. 7, and FIG. 6 is a longitudinal sectional view of a main part with a part cut away.

FIG. 7 is a cross-sectional view of a main part.

FIG. 8 is a schematic diagram showing an example of a combination of a conventional optical axis correcting lens.

FIG. 9 is a schematic view showing another example of a combination of a conventional optical axis correcting lens.

FIG. 10 is a schematic view showing another example of a combination of a conventional optical axis correcting lens.

FIG. 11 is a schematic view showing still another example of the combination of the conventional optical axis correcting lens.

FIG. 12 is a schematic view showing still another example of a combination of conventional optical axis correcting lenses.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Driving mechanism of optical axis correction lens 2 Afocal lens (optical axis correction lens) 3 Concave concave lens (concave lens) 4 Convex convex lens (convex lens) 5 Shooting lens system (main lens system) 6 Suspension 7 Driving means X ′ convex / convex lens Optical axis ( optical axis of convex lens) X main optical axis

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G03B 5/00 G02B 7/02 G03B 5/06 H04N 5/232

Claims (2)

(57) [Claims] 1. A convex lens and the optical axis correction lens disposed in front of the made main lens system of two lenses of a concave lens, perpendicular to the vertical direction and the horizontal direction with respect to the optical axis and to each other
Suspensions supported separately for movement in two directions perpendicular to
And the optical axis correcting lens in two directions orthogonal to each other.
And a driving means for separately moving the lens, wherein the suspension is a convex lens of the optical axis correcting lens.
Lens is always parallel to the main optical axis of the main lens system.
And the driving means moves the convex lens at a predetermined position with respect to the optical axis.
A driving mechanism for the optical axis correcting lens, wherein the driving mechanism is moved in parallel . 2. The method according to claim 1, wherein said convex lens is a convex-convex lens.
The concave lens is a concave lens.
2. A driving mechanism of the optical axis correcting lens according to 1.