JP2023157328A - Lens device and imaging apparatus - Google Patents

Abstract

To provide a lens device advantageous in terms of operability of an operation ring.SOLUTION: A lens device has a stationary barrel, a lens group that is supported by the stationary barrel movably in a direction of an optical axis, and an operation ring that is rotationally operated around the optical axis. The operation ring includes a base that is rotatable while sliding on an outer peripheral part of the stationary barrel, and an exterior part that is fixed to an outer peripheral part of the base. At least one of the base and the exterior part includes a deformation part, and the deformation part has a rigidity in a direction of the diameter centered on the optical axis lower than that of a portion different from the deformation part in a direction of the circumference around the optical axis, due to a hole formed in the direction of the diameter. The lens device has a fixing member that fixes the base and the exterior part with the deformation part therebetween in the direction of the diameter.SELECTED DRAWING: Figure 2

Description

The present invention relates to a lens device and an imaging device.

In cinema lenses used for movie shooting, indicators written on the focus operation ring include meters and feet, which are selected by the cameraman. However, in conventional lenses, the index is formed directly on the focus operation ring, so it is necessary to change the focus operation in order to switch between meters and feet.

A known structure is known in which the operating ring is composed of an index member and a sliding member, which are fixed to each other with screws, and only the index member can be replaced (Patent Document 1).

Japanese Patent Application Publication No. 2003-5008

In the structure of Patent Document 1, the index member is fixed (fastened) to the sliding member with a screw that can move forward and backward in a radial direction centered on the optical axis. Therefore, if the sliding member is deformed by the fastening force of the screw, uneven operating torque or clogging of the operating ring may occur.

An object of the present invention is, for example, to provide a lens device that is advantageous in terms of the operability of the operation ring.

In order to achieve the above object, the lens device of the present invention includes a fixed barrel, a lens group supported by the fixed barrel so as to be movable in the direction of the optical axis, and an operation ring that is rotatably operated around the optical axis. The operating ring includes a base that is rotatable by sliding on the outer periphery of the fixed cylinder, and an exterior portion that is fixed to the outer periphery of the base, and at least one of the base and the exterior portion. One of the deformed parts includes a deformed part, and the deformed part has a rigidity in a radial direction centered on the optical axis due to a hole formed in the radial direction. The fixing member is lower than a portion other than the deformed portion and fixes the base and the exterior portion through the deformed portion in the radial direction.

According to the present invention, it is possible to provide a lens device that is advantageous in terms of the operability of the operating ring, for example.

3 is a cross-sectional view of the lens device of Example 1. FIG. FIG. 3 is an enlarged cross-sectional view of the operation section of the lens device of Example 1. FIG. 3 is an enlarged perspective view of the base of the operating ring of the lens device of Example 1. FIG. 3 is an enlarged perspective view of an operating section in a modification of the lens device of Example 1. FIG. FIG. 7 is a partially enlarged view of the base of the operating ring of the lens device of Example 2; FIG. 7 is a partially enlarged view of the base of the operating ring of the lens device of Example 2; FIG. 7 is a cross-sectional view of a lens device of Example 3. FIG. 7 is an enlarged cross-sectional view of the contact portion of the lens device of Example 3; FIG. 7 is an enlarged perspective view of the base of the operating ring of the lens device of Example 3; FIG. 7 is an enlarged cross-sectional view when the deformation absorbing portion is defined as a region surrounded by a groove. 1 is a conceptual diagram of an imaging device having a lens device of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail based on the accompanying drawings.

A lens device according to Example 1 will be described with reference to FIGS. 1, 2, and 3.
FIG. 1 is a cross-sectional view of a lens device 100 of Example 1. FIG. 2 is an enlarged sectional view of the operation section of the lens device of Example 1. FIG. 3 is an enlarged perspective view of the operating ring base of the lens device 100 of the first embodiment.

The cam barrel 2 is engaged with the fixed barrel 1 so as to be rotatable around the optical axis 50, and is biased by a cam barrel holder 3. The movable lens groups 30 and 40 are engaged with straight grooves and cam grooves (not shown) provided in the fixed barrel 1 and the cam barrel 2, respectively, and are supported movably in the optical axis direction along the optical axis 50. There is.

The operating ring 20 is rotatably engaged with the outer circumference of the fixed barrel 1 via the sliding parts 11 and 12 around the optical axis 50, and has an operating ring presser 6 fixed to the fixed barrel 1. , 7 are biased against the fixed cylinder 1. The cam cylinder 2 and the operating ring 20 are connected by a connecting pin (not shown). By rotating the operation ring 20, the cam cylinder 2 also rotates, and the movable lens groups 30 and 40 move linearly along the optical axis 50 by a linear movement mechanism using a straight groove and a cam groove.

The movable lens groups 30 and 40 are configured to move such that the distance between the movable lens groups 30 and 40 changes during focusing. Note that the movable lens groups 30 and 40 may be configured to move so that the distance between the movable lens groups 30 and 40 changes during zooming.

The operating ring 20 is divided into an operating ring base 4 provided with sliding parts 11 and 12 that slide with respect to the fixed cylinder 1, and an operating ring exterior part 5 provided with gears and indicators. This structure is used to make indicators of different units interchangeable, and to make the operating ring exterior part 5 a resin component for the purpose of weight reduction.

In the plurality of fixing parts (81, 82) provided apart from each other in the circumferential direction with the optical axis 50 as an axis, the operating ring exterior part 5 is located on the outer periphery of the operating ring base 4 with respect to the optical axis 50. It is fixed by a fixing member 8. For example, the fixing member 8 is male threaded. As the fixing parts, a through hole 81 is formed in the operating ring exterior part 5, and a female screw part 82 is formed in the operating ring base 4. By screwing the male thread of the fixing member 8 with the female threaded portion 82 through the through hole 81, the operating ring base 4 and the operating ring exterior portion 5 are fastened and fixed to each other.

The operating ring base 4 has a long hole opening along the circumference around the optical axis 50 between the fixed part (female screw part 82) and the sliding parts 11 and 12 in the direction of the optical axis 50. A deformation absorbing portion (deformation portion) 9 whose width in the optical axis direction and length in the circumferential direction are defined by 9a is provided. The deformation absorbing portion 9 is configured as a region in which at least a portion of its periphery is defined by an elongated opening (hole, through hole) 9a that penetrates in a radial direction centered on the optical axis 50. The deformation absorbing portion 9 of the first embodiment is configured as a region defined by elongated openings (holes, through holes) 9a that are formed discretely around the periphery and penetrate in the radial direction. Further, in the first embodiment, the case where the deformation absorbing portion 9 is defined by openings (holes, through holes) 9a that are discretely formed around the deformation absorbing portion 9 is illustrated, but the opening portion is defined by the deformation absorbing portion 9 (deformation may be formed discretely within the unit.

The deformation absorbing portion 9 in the first embodiment has an end portion in the optical axis direction defined by an opening portion 9a of a long hole passing through in a radial direction with the optical axis 50 as the axis. As a result, the axial force exerted by the fixing member 8 when fixing the operation ring exterior part 5 to the operation ring base 4 is absorbed and alleviated by the deformation absorbing part 9. Therefore, deformation of the sliding parts 11 and 12 of the operating ring base 4 from the perfect circular shape in a cross section perpendicular to the optical axis is suppressed, and clogging and uneven operation of the operating ring 20 during rotation operation can be reduced. .

According to simulations under specific conditions, the amount of deformation on one side of the sliding parts 11 and 12 when the axial force by the fixing member 8 is applied to the operating ring base 4 is 10 μm when the deformation absorbing part 9 is not provided. When the deformation absorbing portion 9 was provided, the thickness was 4 μm, and it was confirmed that deformation was suppressed by 60%. Since the allowable sliding play between the fixed cylinder 1 and the operating ring base 4 is approximately 5 to 20 μm on one side, it can be seen that the suppressing effect of the deformation absorbing portion 9 is superior.

Here, the length L in the circumferential direction around the optical axis 50 of the opening 9a that defines the deformation absorbing portion 9 is defined as t, the thickness in the radial direction around the optical axis of the operating ring base 4.
L≧2t (1)
It is preferable to do so.

In addition, in the first embodiment, the fixing part (female thread part 82) was configured to be located approximately at the center of the circumferential length L around the optical axis 50 of the opening 9a, but the present invention is not limited to this. It will not be done. The fixing portion (female screw portion 82) may be located at a position offset from the center of the circumferential length L with the optical axis 50 of the opening 9a as the axis. In that case, the above conditional expression (1 ). That is, the length of the deformation absorbing portion 9 in the circumferential direction is preferably configured to be at least twice the thickness of the deformation absorbing portion 9 in the radial direction.

In the lens device according to the first embodiment, the deformation absorbing portion 9 was provided on the operation ring base 4, but as in the modification shown in FIG. Even if it is provided in the section 5, the same effect can be achieved. The operation ring exterior portion 5 is provided with a deformation absorbing portion 9 and a linear elongated opening 9b along the circumferential direction around the optical axis 50. The fixing portion (through hole 81) is provided in the deformation absorbing portion 9.

In this way, at least one of the operation ring base 4 and the operation ring outer cover 5 is configured with the deformation absorbing portion 9, which has lower rigidity in the radial direction than the portions at other circumferential positions. The operation ring base 4 and the operation ring exterior part 5 are fixed to each other via the fixed fixing part 82 . With this configuration, the sliding portions 11 and 12 are deformed from a perfect circular shape in a cross section perpendicular to the optical axis due to the axial force of the fixing member 8 that fixes the operating ring exterior portion 5 and the operating ring base 4 to each other. This reduces clogging of the operating ring 20 and uneven operation during rotational operation.

A lens device according to Example 2 will be described with reference to FIGS. 5 and 6.
The lens device according to the second embodiment has the same basic configuration as the first embodiment shown in FIG. In the first embodiment, the deformation absorbing portion 9 was defined by linear elongated openings 9a and 9b along the circumferential direction around the optical axis 50. On the other hand, in the lens device of the second embodiment, the deformation absorbing portion 9 is formed in a U-shaped opening 9c, a U-shaped opening 9d, or a C-shaped opening surrounding the fixing portion 82. It differs from the first embodiment in that it is defined by .

5 and 6 show enlarged views of the operating ring base 4 in the second embodiment.
5 shows a deformation absorbing portion 9 defined by a U-shaped opening 9c surrounding the fixing portion 82, and FIG. 6 shows a deformation absorbing portion 9 defined by a U-shaped opening 9d surrounding the fixing portion 82. Section 9 is shown.

In the second embodiment, one end in the circumferential direction of the two long hole openings 9a of the first embodiment is connected to each other as openings 9c and 9d. With this configuration, the deformation absorbing portion 9 is connected to the main body of the operating ring base 4 only on one side in the circumferential direction with the optical axis 50 as the axis, so that the deformation absorbing portion 9 is shorter in the circumferential direction than the configuration of the first embodiment. Even in the length deformation absorbing portion 9, the radial rigidity can be similarly reduced. As a result, deformation of the sliding portions 11 and 12 from a perfect circular shape in a cross section perpendicular to the optical axis is suppressed, and clogging of the operating ring 20 and uneven operation during rotation operations can be reduced.

A lens device in Example 3 will be described with reference to FIGS. 7, 8, and 9.
FIG. 7 is a cross-sectional view of the lens device of Example 3. FIG. 8 is an enlarged perspective view of the base of the operating ring of the lens device of Example 3. FIG. 9 is an enlarged view of the operating ring base 4 in Example 3.

FIG. 7 shows a cross section of the lens barrel showing that the operating ring exterior part 5 is provided with contact parts 13 that contact the contact parts 14 of the operating ring base 4 at three locations in the circumferential direction around the optical axis. Show the diagram. In this structure, when the operation ring exterior part 5 is made of resin for the purpose of reducing weight, the contact area between the operation ring base 4 and the operation ring exterior part 5 does not cover the entire circumference.

FIG. 8 is an enlarged sectional view of the contact portion 13 in the sectional view of the lens barrel shown in FIG. FIG. 9 is an enlarged perspective view of the contact portion 13 of the operating ring base 4. As shown in FIG.

As shown in FIG. 8, fixing portions 81 and 82 and deformation absorbing portion 9 are provided within a circumferential length LC of contact portion 13. As shown in FIG. Thereby, it is possible to make it difficult to transmit the influence of the axial force by the fixed member 8 to the sliding parts 11 and 12.

In the third embodiment, the deformation absorbing portion 9 is provided on the operating ring base portion 4, but the deformation absorbing portion 9 may be provided on the operating ring exterior portion 5.

In Examples 1 to 3, the deformation absorbing portion 9 is defined by openings (holes, through holes) 9a to 9d that penetrate in the radial direction. However, as shown in FIG. 10, the operating ring base 4 may be configured such that at least a portion of its periphery is defined by a groove 9e that does not penetrate in the radial direction centered on the optical axis. Note that when the deformation absorbing portion 9 is provided in the operating ring base 4, a groove 9e that does not penetrate in the radial direction centered on the optical axis is formed in the operating ring base 4 so as to define a part of the periphery of the deformation absorbing portion 9. It may be provided.

(imaging device)
An imaging device 300 (FIG. 11) having the effects of the invention is realized by the lens device 100 of the invention and the camera device 200 including an image sensor 201 that takes (captures) an image formed by the lens device 100. be able to.

The disclosure of this embodiment includes the following configurations.
(Configuration 1)
A fixed tube,
a lens group supported by the fixed barrel so as to be movable in the direction of the optical axis;
an operating ring that is rotated around the optical axis;
The operation ring includes a base that is rotatable by sliding on the outer periphery of the fixed cylinder, and an exterior part that is fixed to the outer periphery of the base,
At least one of the base portion and the exterior portion includes a deformed portion, and the deformed portion has a rigidity in a radial direction centered on the optical axis due to a hole formed in the radial direction. lower than a portion different from the deformed portion in the direction of the surrounding circumference,
A lens device comprising a fixing member that fixes the base portion and the exterior portion via the deformed portion in the radial direction.
(Configuration 2)
The lens device according to configuration 1, wherein the hole is formed in at least a portion of the periphery of the deformed portion.
(Configuration 3)
The lens device according to configuration 2, wherein the hole is a through hole formed in a part of the periphery of the deformed portion in the radial direction.
(Configuration 4)
3. The lens device according to configuration 3, wherein the hole is formed in a U-shaped, U-shaped, or C-shaped area around the deformed portion.
(Configuration 5)
The lens device according to configuration 1, wherein the holes are formed discretely.
(Configuration 6)
5. The lens device according to configuration 5, wherein the holes are formed discretely around the deformed portion.
(Configuration 7)
7. The lens device according to configuration 5 or 6, wherein the holes are formed discretely within the deformed portion.
(Configuration 8)
8. The lens device according to any one of configurations 1 to 7, wherein the length of the deformed portion in the circumferential direction is at least twice the thickness of the deformed portion in the radial direction.
(Configuration 9)
9. The lens device according to any one of configurations 1 to 8, wherein the deformation portions are arranged at at least three locations in a circumferential direction around the optical axis.
(Configuration 10)
An imaging device comprising the lens device according to any one of Structures 1 to 9, and an image sensor that takes an image formed by the lens device.

1: Fixed cylinder 4: Operating ring base 5: Operating ring exterior part 8: Fixed member 9: Deformation absorbing part 11, 12: Sliding part

Claims (10)

A fixed tube,
a lens group supported by the fixed barrel so as to be movable in the direction of the optical axis;
an operating ring that is rotated around the optical axis;
The operation ring includes a base that is rotatable by sliding on the outer periphery of the fixed cylinder, and an exterior part that is fixed to the outer periphery of the base,
At least one of the base portion and the exterior portion includes a deformed portion, and the deformed portion has a rigidity in a radial direction centered on the optical axis due to a hole formed in the radial direction. lower than a portion different from the deformed portion in the direction of the surrounding circumference,
A lens device comprising a fixing member that fixes the base portion and the exterior portion via the deformed portion in the radial direction. The lens device according to claim 1, wherein the hole is formed in at least a portion of the periphery of the deformed portion. 3. The lens device according to claim 2, wherein the hole is a through hole formed in a part of the periphery of the deformed portion in the radial direction. 4. The lens device according to claim 3, wherein the hole is formed in a U-shaped, U-shaped, or C-shaped area around the deformed portion. The lens device according to claim 1, wherein the holes are formed discretely. 6. The lens device according to claim 5, wherein the holes are formed discretely around the deformed portion. 6. The lens device according to claim 5, wherein the holes are formed discretely within the deformed portion. The lens device according to claim 1, wherein the length of the deformed portion in the circumferential direction is at least twice the thickness of the deformed portion in the radial direction. The lens device according to claim 1, wherein the deformation portions are arranged at at least three locations in a circumferential direction around the optical axis. An imaging device comprising: the lens device according to any one of claims 1 to 9; and an image sensor that takes an image formed by the lens device.

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