JPH05164953A - Zoom system optical block - Google Patents

Abstract

PURPOSE:To increase the degree of freedom of the arrangement of a zoom drive member and the operation direction of an operation member by excellently shielding the zoom system optical block from light and protecting it against dust. CONSTITUTION:This zoom system optical block has a cover 3 for light shielding and dust protection and a zoom shaft 1 which is arranged in the cover 3 in parallel to the optical axis and moves lens barrels 5 and 6 in parallel to the optical axis, and is incorporated in an image pickup device. Only the rear end part of the zoom shaft 1 is exposed to the outside of the cover 3, a pinion 2 or helical gear 2-1 is provided at the rear end part of the zoom shaft 1, and the operation member 10 is engaged with the pinion 2 or helical gear 2-1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a zoom system optical block which is incorporated in an image pickup device and performs a zoom operation, more specifically, light shielding and dustproof are improved, and a degree of freedom in arrangement of a zoom driving member is increased. Further, the present invention relates to a zoom system optical block in which the operation position in the zoom operation is clarified.

[0002]

2. Description of the Related Art Conventionally, a zoom system optical block is roughly classified into two types, that is, one for performing a zoom operation by driving a cam ring or a plate cam and one for performing a zoom operation by rotating a zoom shaft. can do.

The following describes these systems with reference to FIGS.
It will be specifically described based on.

FIG. 11 shows a conventional example of a cam ring system, in which a cam groove is cut in a cylinder arranged outside the optical block to form a cam ring 13, which is provided on the lens barrels 5 and 6. By engaging the follower pins 5a and 6a thus obtained with the grooves and rotating the cam ring 13, the lens barrel is moved in parallel with the optical axis to perform a zoom operation. A substantially similar zoom operation can be performed by using a plate cam instead of the cam ring 13.

FIG. 12 shows a conventional example of rotation of the zoom shaft. In FIG. 12, a lead screw is cut on the zoom shaft 1 arranged parallel to the optical axis in the light-blocking cover 3 of the optical block.
The screw is engaged with a screw engaging portion provided on the lens barrel 5, and a zoom gear provided on the zoom shaft 1 or a gear interlocking member that interlocks with the zoom gear is exposed outside the optical block. When zooming, the exposed gear interlocking member is operated to rotate the zoom shaft and move the lens barrel with the lead screw to perform the zoom operation.

[0006]

The above-mentioned two types of conventional examples have the following drawbacks, respectively.

B. In case of cam ring and plate cam The cam ring or plate cam required for zoom operation is arranged on the outermost side of the optical block, and the follower pin moves in the cam groove provided in these, so the groove part inside and outside the optical block. Can not be shielded, it is impossible to completely block light and prevent dust.

Further, since it is necessary to drive a large member such as a cam ring or a plate cam which has a limited operation, it is possible to freely arrange the driving member for driving the cam and the operating direction (rotation or rectilinear movement) of the operating member. I lose my degree.

B. In case of zoom shaft Since the lens barrel is moved by the lead screw cut on the zoom shaft without using the cam ring or the plate cam, the opening of the optical block by the cam groove can be prevented. However, a zoom gear for driving the zoom shaft and an opening for exposing the interlocking member to the outside of the optical block are required, and sufficient light shielding and dust prevention cannot be expected.

The present invention is intended to solve the above problems and provides a zoom system optical block which has a high degree of freedom in the arrangement of the zoom driving member and the operating direction of the operating member while improving the light shielding and dustproof. It is intended to be provided.

[0011]

In order to achieve the above object, a zoom system optical block according to the present invention includes a light-blocking and dust-proof cover and a lens barrel which is disposed in the cover in parallel with the optical axis. A zoom system optical block to be moved in parallel with the axis, and in a zoom system optical block incorporated in an imaging device, only a rear end of the zoom shaft is exposed outside the cover, and a pinion is provided at a rear end of the zoom shaft. The operation member is engaged with the pinion.

[0012]

The zoom optical block according to the present invention includes a light-shielding and dust-proof cover and a cover arranged parallel to the optical axis.
In a zoom system optical block having a zoom shaft for moving a lens barrel in parallel with an optical axis, and only a rear end of the zoom shaft is exposed outside the cover in a zoom system optical block incorporated in an image pickup device, and a pinion is mounted at a rear end of the zoom shaft. Since the operation member is engaged with the pinion, the zoom shaft is rotated by operating the operation member, and the lens barrel is moved in parallel with the optical axis by the rotation of the zoom shaft. The action is taken.

[0013]

FIG. 1 shows a first embodiment of the present invention.

In FIG. 1, reference numeral 1 denotes a zoom shaft on which a screw 1-1 for moving the front lens barrel 5 is formed and a cam 8 for moving the rear lens barrel 6 is fixed. The zoom axis 1 is set parallel to the optical axis X. Reference numeral 3 denotes an entire light-shielding / dust-proof cover that covers the front and side surfaces of the optical system, and 4 denotes a mount light-shielding / dust-proof cover that covers the rear surface of the optical system and has an image sensor 7 attached thereto. Achieve shading and dustproof. A protective glass 3-1 is provided on the end plate portion of the cover 3. Only the rear end portion 1-2 of the zoom shaft 1 penetrates the cover 4 and is exposed to the outside, and the pinion gear 2 is fixed to the rear end portion 1-2.

Reference numeral 9 is a guide shaft for guiding the front lens barrel 5 and the rear lens barrel 6. Reference numeral 10 denotes a slide operating member which is attached to the exterior structure 14 by the structure and the like so as to be reciprocally movable or rectilinearly moved. The operating member 10 includes a rack portion 10-1 that engages with the pinion 2 and an operating portion 10 that is offset from directly above the pinion gear 2, that is, separated from the rack and pinion engaging portion by a predetermined distance.
-2 and an elastic portion 10-3 provided between the rack portion 10-1 and the operation portion 10-2. As shown in FIG. 1, the zoom optical system including the zoom shaft 1, the front group lens barrel 5, the rear group lens barrel 6, the image pickup device 7, the rear group cam 8 and the guide shaft 9 is provided with the entire light-shielding / dustproof cover 3. The mount is housed in a light-shielding / dust-proof cover 4, and the covers 3 and 4 shield light and dust other than light necessary for front-side imaging.
The optical block having the above configuration is incorporated in the image pickup device.

In the above structure, the pinion gear 2 and the operating member 10 for zooming are exposed outside the cover.
Also, only the rear end portion 1-2 of the zoom shaft 1 has a clearance only in the bearing portion of the zoom shaft 1, and thus practically sufficient shading and dustproof can be achieved. Even if there is a leak of light or the like, it is easy to provide a light shielding means to the bearing portion.

When a zoom operation is performed, the operation member 10 is slid in the direction of the arrow to move the pinion gear 2
To rotate the zoom shaft 1. Along with this rotation, the front lens barrel 5 is moved in a predetermined manner by the lead screw 1-1 and the rear lens barrel 6 is moved by the rear cam 8 to perform a zoom operation. Here, since the slide operation member 10 used for the zoom operation is attached to the exterior structure 14 and has the elastic portion 10-3 as described above, even when a force is applied to the operation portion, Since the force is absorbed by the backlash amount of the pinion gear 2 and the deformation amount of the elastic portion 10-3, the operating force is not directly transmitted to the optical block. In addition, the operation direction of the operation member 10 can be a slide operation in a direction orthogonal to the optical axis X, which is considered to be the most convenient for the image pickup apparatus.

FIG. 2 shows a second embodiment of the present invention, in which the pinion gear 2 is engaged with a rotary operation member 11 composed of a gear portion 11-1 and an operation portion 10-2. The operation of the pinion gear 2 is basically the slide or linear operation of the first embodiment, but depending on the layout of the image pickup apparatus, it is easy to perform the rotary operation by using the rotary operation member of the second embodiment. Therefore, the degree of freedom in design is increased.

In the first and second embodiments described above, the desired object of the present invention, namely, light shielding and dustproofing, can be sufficiently achieved. However, when the optical system block of the first embodiment is provided with a macro function which is generally used in cameras such as video cameras and still video cameras, there may be difficulty in operation. That is, as shown in FIGS. 3 and 4, when the operation member 10 is slid along the groove 20, the wide macro position is set ahead of the wide position. Since all the movements are performed by the same rotation of the zoom shaft 1, the movement of the operation member 10 is also the same until the movement from tele to wide to wide macro. That is, when operating the operating member 10, even if one end is in the tele position, the other end becomes a wide macro position beyond the wide position, and it may be difficult to stop at the wide position. is there. Further, when the rotation angle of the zoom shaft from the wide position to the wide macro position is small, the movement amount of the macro operation of the operation unit is reduced accordingly, and macro switching is unclear and cannot be fully recognized.

In order to solve these problems, it is generally possible to provide a mechanism for adding one operation or a separate mechanism for macro operation when entering the macro area from the wide position. Each of these means adds another mechanism, and the advantages of a simple and reliable zoom mechanism are lost.

The present invention is intended to further improve the above problems, and its embodiments will be described below. In the following embodiments, the same members and parts as those in the first embodiment are designated by the same reference numerals.

5 and 8 show a third embodiment of the present invention.
In the figure, a helical gear 2-1 having a predetermined thickness in the axial direction is fixed to the rear end portion of the zoom shaft 1.
The operation member 10 includes a rack portion 10-1 that engages with the helical gear 2-1, an operation portion 10-2 that is offset from directly above the helical gear 2-1, and an elastic portion 10 provided between them. -3. Further, an L-shaped groove 21 is cut in the exterior structure or the like, and the operation member 10 is guided in the front, rear, left, and right directions by the groove 21, and the rack portion 10-1 is pressed against and separated from the helical gear 2-1. Direction guides are also provided as in the first embodiment. In the embodiment, the orthogonal portion 2 with respect to the optical axis X of the groove 21 or the zoom axis 1
The upper end (upper end in FIG. 5) of 1-1 is set to the tele position, the lower end is set to the wide position, and the rear end (right end in FIG. 5) of the groove portion 21-2 parallel to the optical axis X is set to the wide macro position. To do.
Next, the operation of the embodiment will be described.

First, when the operating member 10 is at the tele position (FIG. 8A), the zoom shaft 1 is also at the position of the predetermined rotation angle at the time of tele, and accordingly the front lens barrel 5 and the rear lens barrel 6 are attached. Is also set to a predetermined tele position.

The focal length is the longest position.

Next, when the operating member 10 is moved from the tele position to the wide position, the operating gear member 10-1 moves along with the movement in the direction orthogonal to the zoom axis of the operating member.

A lead screw portion 1-1 is provided on the zoom shaft, whereby the front lens barrel 5 moves to a position corresponding to the rotation.

A zoom cam 8 is attached to the zoom shaft 1 and integrally rotates, and the lead of this cam also moves the rear lens barrel 6 to a position corresponding to the rotation.

At this time, the positions of the front lens barrel 5 and the rear lens barrel 6 have a relationship in which the focal lengths thereof are gradually shortened in accordance with the amount of movement of the operating member.

When the operating member 10 reaches the wide position (FIG. 8B), the zoom shaft is also at the position of the predetermined wide angle of rotation, and accordingly the front lens barrel 5 and the rear lens barrel 6 are also in the predetermined positions. Is set to the wide position.

The focal length is the shortest except for macro time.

Further, the operating member 10 does not move in the wide direction (direction orthogonal to the zoom axis).

When the operating member 10 enters the macro area,
With the movement of the operation member in the direction parallel to the zoom axis, the operation gear member also moves in the direction parallel to the zoom axis.

Since the gear with which the operating gear member 10-1 is engaged is a helical gear, the zoom shaft 1 rotates due to the lead angle even when the gear member moves parallel to the shaft, and enters the macro range. enter.

When the operating member 10 has reached the wide / macro position (FIG. 8C): As in the case of the tele position and the wide position, the zoom shaft 1, the front group lens barrel 5, and the rear group lens barrel 6 are predetermined. Is set to the wide macro position of.

The operating member 10 is restricted so that it cannot move in a direction parallel to the zoom shaft 1 until it reaches the wide position.

A fourth embodiment of the present invention is shown in FIGS. In these figures, the groove 22 is a groove portion 22-1 orthogonal to the zoom axis 1 or the optical axis, and a groove portion 22-parallel to the zoom axis.
It is composed of 2 and has an inverted L shape. And the groove 22
-The lower end of -1 is the wide position, the upper end is the tele position, and the groove 22-
The front end of 2 is set to the tele macro position.

In the fifth embodiment shown in FIGS. 7 and 10, the groove 23 is a groove portion 23- which is orthogonal to the zoom axis or the optical axis.
1. It has groove portions 23-2 and 23-3 parallel to the zoom axis and has a Z shape. The upper end of the groove 23-1 is set to the tele position, the lower end is set to the wide position, the front end of the groove 23-2 is set to the tele macro position, and the rear end of the groove 23-3 is set to the wide macro position.

In the fourth and fifth embodiments, the structure other than the groove is the same as that of the third embodiment, and the operation of the operating member 10 also changes in accordance with the change in the shape of the grooves 22 and 23. The operation of the operating member 10 of the third embodiment is essentially the same.

The following effects can be obtained in the above third to fifth embodiments.

A macro mechanism can be achieved without using a complicated mechanism.

A macro mechanism with good operability in which the ends of the zoom operation are in the tele and wide positions.

Since the moving directions of the operation members for zoom operation and macro operation are different, it is easy to distinguish between zoom and macro.

The stroke of macro operation can be changed by selecting the helical gear.

[0044]

As described above, according to the present invention,
In the zoom optical block, only the rear end of the zoom shaft is exposed outside the cover, the pinion or the helical gear is provided at the rear end of the zoom shaft, and the operation member is engaged with the pinion or the helical gear. Therefore, the optical block can be shielded from light and dust can be satisfactorily protected, and the degree of freedom in the arrangement of the zoom driving member and the operating direction of the operating member can be increased.

[Brief description of drawings]

FIG. 1 is a diagram showing a first embodiment of a zoom system optical block according to the present invention.

FIG. 2 is a diagram showing a second embodiment of the zoom system optical block according to the present invention.

FIG. 3 is an operation explanatory view of the first embodiment of the present invention.

FIG. 4 is a detailed view of an operation portion according to the first embodiment of the present invention.

FIG. 5 is a diagram showing a third embodiment of the zoom system optical block according to the present invention.

FIG. 6 is a diagram showing a fourth embodiment of the zoom system optical block according to the present invention.

FIG. 7 is a diagram showing a fifth embodiment of the zoom system optical block according to the present invention.

FIG. 8 is a detailed view of an operation portion of the third embodiment of the present invention.

FIG. 9 is a detailed view of the operating portion of the fourth embodiment of the present invention.

FIG. 10 is a detailed view of the operating portion of the fifth embodiment of the present invention.

FIG. 11 is a diagram showing an example of a conventional zoom system optical block.

FIG. 12 is a diagram showing another example of a conventional zoom system optical block.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Zoom axis 2 ... Pinion 2-1 ... Helical gear 3 ... Whole light-shielding / dust-proof cover 4 ... Mount light-shielding / dust-proof cover 5 ... Front group lens barrel 6 ... Rear group lens barrel 7 ... Imaging element 8 ... Rear group cam 10 ... Operation member 10-1 ... Rack (gear) portion 10-2 ... Operation portion 10-3 ... Elastic portion 20, 21, 2
2, 23 ... Groove

Claims (3)

[Claims] 1. A zoom system optical block having a light-shielding and dust-proof cover and a zoom shaft arranged in the cover in parallel with the optical axis for moving a lens barrel in parallel with the optical axis and incorporated in an image pickup apparatus. 2. A zoom optical system block, wherein only the rear end of the zoom shaft is exposed to the outside of the cover, a pinion is provided at the rear end of the zoom shaft, and an operating member is engaged with the pinion. 2. The operating member includes a rack portion that engages with the pinion, an operating portion that is offset from directly above the pinion gear, and an elastic portion that is provided between the rack portion and the operating portion. The zoom system optical block according to claim 1, wherein the zoom system optical block drives a pinion gear. 3. A zoom system optical block having a light-shielding and dust-proof cover and a zoom shaft arranged in the cover in parallel with the optical axis for moving a lens barrel in parallel with the optical axis, and incorporated in an image pickup apparatus. In the above, only the rear end of the zoom shaft is exposed to the outside of the cover, and the rear end of the zoom shaft is provided with a helical gear having a predetermined thickness in the zoom shaft direction. And an operating member that is movable in a direction parallel to the zoom axis is provided. When the operating member is operated in a direction orthogonal to the zoom axis, the zoom operation operates the operating member in a direction parallel to the zoom axis. The zoom optical block is characterized in that each macro operation is performed by.