JP2000171871A - Foreign matter adhesion preventing device for optical device, optical equipment and lens device provided therewith - Google Patents

Abstract

PROBLEM TO BE SOLVED: To sufficiently utilize an optical device and optical equipment such as a lens device using the optical device while removing a foreign matter such as dust and waterdrops adhering to the outer surface of the optical device without adversely influencing the performance of the optical device however often they are used. SOLUTION: The waterdrop adhesion preventing device of the optical device is equipped with a rotational holding means including a filter holding ring 16 concentrically holding a filter 14 being a kind of optical device exposed to external space, and a filter coupling ring 18 concentrically rotatably holding the ring 16 through a rotational supporting means 20 such as a ball bearing mechanism, for example; and a rotational driving means including a rotational driving source 24 such as a motor for rotating the ring 16 of the rotational holding means through an output gear 28 meshed with the internal gear 22 of the ring 16 and a gear accelerating mechanism 26.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for preventing foreign matter from adhering to an optical element, an optical device having the device, and a lens device having the device.

[0002]

2. Description of the Related Art In an optical device using an optical element, for example, dust and water droplets adhered to an external space exposed surface (outer surface) of the optical element in order to prevent malfunction and to remove unnecessary foreign matter in the field of view. It is widely known that it is important to remove foreign substances. When foreign matter such as dust or water drops adheres to the outer surface of an optical element in a usual conventional optical device, a user of the optical device or an assistant thereof may use a relatively soft object such as a brush or a towel. Foreign substances such as dust and water droplets are wiped off or wiped off from the outer surface of the optical element. However, the user of the optics or his assistant does not always hold relatively soft objects, such as brushes and towels.

An optical device with a wiping member has been developed to enable a user of the optical device to easily and easily remove foreign matters such as dust and water droplets attached to the outer surface of the optical element at any time. JP-A-59-131725 and Shokai 5
No. 9-134133.

The former Japanese Utility Model Application Laid-open No. Sho 59-131725 discloses a camera as an optical device in which a slide-type lens opening / closing lid is provided in an exterior housing.
In this conventional camera, a wiper member is attached to the back surface of the lens opening / closing lid, and the wiper is slid every time the lens opening / closing lid is slid between the lens protection position covering the lens and the lens opening position exposing the lens. The member wipes the outer space exposed surface (outer surface) of the lens, and if foreign matter such as dust or water droplets adheres to the outer surface of the lens, the foreign material such as dust or water droplet is wiped off by the wiper member.

The latter Japanese Utility Model Application Laid-Open No. 59-134133 discloses a camera as an optical device in which a flap-type lens opening / closing lid is provided in an exterior housing.
In this conventional camera, a wiper member is attached to the rear surface at the end of the lens opening / closing lid, and while moving the lens opening / closing lid from the lens protection position covering the lens to the lens opening position exposing the lens. If foreign matter such as dust or water drops adheres to the external space exposed surface (outer surface) of the lens,
The outer surface of the lens can be wiped using a wiper member, and foreign matters such as dust and water droplets are wiped off by the wiper member.

[0006]

In any of the above-mentioned various conventional examples, foreign matters such as dust and water droplets adhering to the outer space exposed surface (outer surface) of the optical element are relatively soft such as brushes and towels. It is wiped or wiped off by an object or a wiper member. In this case, a relatively soft object or a wiper member comes into direct contact with the outer space exposed surface (outer surface) of the optical element. Therefore, if the relatively soft object or the wiper member is used many times and becomes dirty, the relatively soft object is removed. Every time the wiper member wipes foreign matter such as dust or water droplets or wipes, dirt is rubbed from the relatively soft object or wiper member onto the outer space exposed surface (outer surface) of the optical element. This contamination has an adverse effect on the performance of the optical element.

[0007] Also, the outer space exposed surface (outer surface) of the optical element
When the surface treatment is performed, the surface treatment is deteriorated or damaged by a relatively soft object or repeated sliding of the wiper member on the outer surface. This also reduces the performance of the optical element.

Furthermore, while the relatively soft object or the wiper member is used to wipe or wipe foreign matter such as dust and water droplets on the exposed surface (outer surface) of the optical element, the exposed surface of the optical element is exposed. Most of the (outer surface) is covered by a relatively soft object or a wiper member, making it impossible to make full use of optical elements, and thus making full use of optical devices such as lens devices using optical elements. Can not.

The present invention has been made under the circumstances described above, and it is an object of the present invention to provide an optical element having no adverse effect on the performance of the optical element or reducing the performance of the optical element even if used many times. While removing foreign matter such as dust and water droplets attached to the exposed surface (outer surface) of the space, the optical element can be fully utilized, and as a result, optical equipment such as a lens device using the optical element can be sufficiently used. Can be used,
Water droplet adhesion preventing device for optical element, optical device equipped with the same,
Another object of the present invention is to provide a lens device having the same.

[0010]

In order to achieve the above-mentioned object of the present invention, a device for preventing foreign matter from adhering to an optical element according to the present invention comprises: an optical element exposed to an external space is moved around its own optical axis. A rotation holding means rotatably held; and a rotation driving means for rotating the rotation holding means.

In the apparatus for preventing foreign matter from adhering to an optical element according to the present invention having the above-described structure, foreign matter such as dust and water droplets adhering to an external space exposed surface (outer surface) of the optical element is removed. When removing, the rotation holding means is rotated by the rotation driving means to rotate the optical element around its own optical axis. At this time, the dust and water droplets are removed by the centrifugal force generated in the foreign matter such as the dust and water droplets. The foreign material is repelled from the outer space exposed surface (outer surface) of the optical element outward in the radial direction of the outer space exposed surface. During this time, nothing other than the foreign matter such as the dust and water droplets comes into contact with the outer space exposed surface (outer surface) of the optical element.

In order to achieve the above-mentioned object of the present invention, an optical apparatus provided with a device for preventing foreign matter from adhering to an optical element according to the present invention comprises: And a rotation driving means for rotating the rotation holding means.

[0013] Also in the optical device having the optical element foreign matter adhesion preventing device according to the present invention having the above-described structure, the optical element adheres to the external space exposed surface (outer surface) of the optical element. When removing foreign matter such as dust and water droplets, the rotation driving means rotates the rotation holding means to rotate the optical element around its own optical axis. At this time, the centrifugal force generated in the water droplets causes the dust to be removed. Foreign matter such as water and water droplets are repelled from the outer space exposed surface (outer surface) of the optical element outward in the radial direction of the outer space exposed surface. During this time, nothing other than the foreign matter such as the dust and water droplets comes into contact with the outer space exposed surface (outer surface) of the optical element.

In order to achieve the above object of the present invention, a lens device provided with a device for preventing foreign matter from adhering to an optical element according to the present invention comprises: And a rotation driving means for rotating the rotation holding means.

[0015] In the lens device having the optical element foreign matter adhesion preventing device according to the present invention having the above-described structure, the lens device adheres to the external space exposed surface (outer surface) of the optical element. When removing foreign matter such as dust or water droplets, the rotation driving means rotates the rotation holding means to rotate the optical element around its own optical axis. Due to the centrifugal force, the foreign matter such as dust and water droplets is repelled from the outer space exposed surface (outer surface) of the optical element outward in the radial direction of the outer space exposed surface. During this time, nothing other than the foreign matter such as the dust and water droplets comes into contact with the outer space exposed surface (outer surface) of the optical element.

In order to achieve the above-mentioned object of the present invention, a lens device having a device for preventing foreign matter from adhering to an optical element according to the present invention is also provided: a lens detachably connected to a camera having a rotary drive source. Rotation holding means for holding an optical element exposed to an external space rotatably around its own optical axis in the device; and provided in the lens device, wherein the rotation drive is performed when the lens device is connected to the camera. A torque transmitting means for transmitting a torque from the source to the rotation holding means.

In the lens device having the optical element foreign matter adhesion preventing device according to the present invention characterized in that the lens device is detachably connected to the camera. When removing foreign matter such as dust and water droplets adhered to the external space exposed surface (outer surface) of the optical element, the optical element is rotated by rotating the rotation holding means via the rotational force transmitting means by the rotation driving source of the camera. The optical element is rotated around its own optical axis. At this time, the foreign matter such as the dust and water droplets is removed from the external space exposed surface (outer surface) of the optical element by the centrifugal force generated by the foreign material such as the dust and water droplets. Will be repelled outward in the radial direction. During this time, nothing other than the foreign matter such as the dust and water droplets comes into contact with the outer space exposed surface (outer surface) of the optical element.

An apparatus for preventing foreign matter from adhering to an optical element according to the present invention, which is configured variously as described above,
In each of the optical device provided with the foreign matter adhesion preventing device of the optical element and the lens device provided with the foreign matter adhesion preventing device of the optical element, the surface exposed to the external space of the optical element has water repellency. Needless to say, it is preferable.

Hereinafter, a lens device having a device for preventing foreign matter from adhering to an optical element according to various embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, a lens device provided with a device for preventing foreign matter from adhering to an optical element according to a first embodiment of the present invention will be described with reference to FIG.

A lens device 10 shown in FIG. 1 is a part of a camera which is a kind of optical equipment, and includes a camera body 12.
A base 10a detachably connected to the lens mounting ring 12a, and a lens barrel 10 fixed to the base 10a and holding various lenses 10c in a predetermined arrangement along the optical axis 10b.
d. Some of the various lenses 10c are not shown in the camera body 12 by operating a focusing operation ring (not shown) concentrically arranged with the optical axis 10b on the outer peripheral surface of the lens barrel 10d. It moves within a predetermined range to form an image of the subject on the film surface. An aperture member (not shown) that is operated by operating an aperture operation ring (not shown) concentrically arranged with the optical axis 10b on the outer peripheral surface of the lens barrel 10d is further disposed in the lens barrel 10d. Then, the lens device 10 of FIG.
Are known.

In the lens device 10, the lens barrel 10
A filter 14 which is a kind of an optical element is rotatably connected concentrically to the optical axis 10b to a free end of d. Describing in more detail, the filter 14 is held concentrically with respect to the optical axis 10b by a filter holding ring 16 arranged concentrically with respect to the optical axis 10b. The outer peripheral surface is screwed into a known filter threaded annular groove 10e at the free end of the lens barrel 10d, and is concentric with the optical axis 10b via a rotation support means 20 such as a ball bearing mechanism. It is rotatably supported.

An internal gear 22 is formed on the inner peripheral surface of the filter holding ring 16 inwardly of the filter 14 and concentrically with respect to the optical axis 10b. A rotational force is transmitted to the internal gear 22 from an output shaft of a motor serving as a rotational drive source 24 installed in the lens barrel 10d, for example, via a gear speed increasing mechanism 26, and is disposed at a free end of the lens barrel 10d. Output gear 28 is meshed. The lens barrel 10
filter holding ring 16 for output gear 28 at the free end of d
The meshing of the internal gear 22 on the inner peripheral surface and the release of the meshing are achieved by screwing the outer peripheral surface of the filter connecting ring 18 into the filter screwing annular groove 10e at the free end of the lens barrel 10d and releasing the screwing.

In the lens device 10 configured as described above, when foreign matter such as dust or water drops adheres to the outer space exposed surface (outer surface) of the filter 14, the rotation drive source 24 is operated to rotate the filter. When the filter holding ring 16 is rotated by the rotational force from the output shaft of the source 24, the filter 1
A centrifugal force acts on foreign substances such as dust and water droplets on the external space exposed surface (external surface) of the filter 4, and the centrifugal force causes the foreign substances to be washed off from the external space exposed surface (external surface) of the filter 14. .

As described above, since anything other than the centrifugal force does not act on foreign matters such as dust and water droplets on the outer space exposed surface (outer surface) of the filter 14, the outer space exposed surface (outer surface) of the filter 14 is not affected. ) Does not stain or damage the outer surface when removing the foreign matter. Then, the optical performance of the filter 14 is not affected. Further, even if the filter 14 is rotated during photographing, or the filter 14 is kept rotated, the camera can be fully utilized.

As described above, the action of removing the foreign matter from the outer space exposed surface (outer surface) of the filter 14 by using the centrifugal force is performed by the outer space exposed surface (outer surface) of the filter 14.
Has higher water repellency, it can be further enhanced. Making the outer space exposed surface (outer surface) of the filter 14 water-repellent can be performed, for example, by performing a water-repellent treatment on the outer space exposed surface (outer surface) of the filter 14.

The motor serving as the rotary drive source 24 is constructed by incorporating a driving force conversion mechanism or a driving force extraction mechanism into the gear speed increasing mechanism 26 to thereby control the predetermined several of the various lenses 10c in the lens barrel 10d. It can also be used for movement for focusing.

From the above description with reference to FIG. 1, the rotation holding means for holding the filter 14 which is a kind of the optical element exposed to the external space in the above-described embodiment so as to be rotatable around its own optical axis. It is clear that the filter holding ring 16 and the filter connecting ring 18 and the rotation supporting means 20 such as a ball bearing mechanism between them constitute the rotation driving source 24 and the gear speed increasing mechanism 26 and the output gear 2.
8, and the filter holding ring 16 of the rotation holding means is rotated via the internal gear 22 of the filter holding ring 16.
In this embodiment, the rotation driving means for rotating the filter holding ring 16 of the rotation holding means includes a rotation driving source 24, a gear increasing mechanism 26, an output gear 28, and an internal gear of the filter holding ring 16. 22 is constituted.

Next, a lens device having a device for preventing foreign matter from adhering to an optical element according to a second embodiment of the present invention will be described with reference to FIG.

Most of the configuration of the lens device 30 according to the second embodiment is substantially the same as the configuration of the lens device 10 according to the first embodiment of the present invention described above with reference to FIG. Therefore, the configuration of the lens device 30 according to the second embodiment shown in FIG. 2 is the same as that of the first embodiment of the present invention described above with reference to FIG. The same components as those of the lens device 10 are denoted by the same reference numerals, and a detailed description of these components will be omitted.

The structure of the lens device 30 according to the second embodiment is different from the structure of the lens device 10 according to the first embodiment described above in that the rotational drive for transmitting the rotational force to the gear speed increasing mechanism 26 is different. The motor as the source 32 is the camera body 1
2 is provided. For this reason, the rotary drive source 3
2, a rotational force transmitting shaft 32a for transmitting a rotational force from an output shaft (not shown) extends parallel to the optical axis 10b from the lens attachment / detachment ring 12a of the camera body 12 in the same direction as the optical axis 10b. The engaging projection at the projecting end of the rotational force transmitting shaft 32a is engaged with the engaging groove of the input gear 26a in the gear speed increasing mechanism 26 at the base end of the lens barrel 10d of the lens device 30. I agree. The engagement and the release of the engagement are performed when the base end of the lens barrel 10d of the lens device 30 is attached to and detached from the lens attachment / detachment ring 12a of the camera body 12.

The lens device 30 according to the second embodiment shown in FIG. 2 operates similarly to the lens device 10 according to the above-described second embodiment shown in FIG. The same effect can be obtained.

From the above description with reference to FIG. 2, the rotation holding means for holding the filter 14 which is a kind of the optical element exposed to the external space in the above embodiment rotatably around its own optical axis. The rotation driving means for rotating the filter holding ring 16 constituting a part includes a rotation driving source 32, a torque transmission shaft 32a, a gear increasing mechanism 26 including an input gear 26a, an output gear 28, and a filter holding mechanism. The internal gear 22 of the ring 16 constitutes.

Next, an apparatus for preventing foreign matter from adhering to an optical element according to a third embodiment of the present invention will be described with reference to FIGS. 3A and 3B.

The device 40 for preventing foreign matter from adhering to an optical element shown in these figures is detachable from a known filter screw-in annular groove at a free end of a lens barrel which is a part of a camera which is a kind of optical equipment. Fixed to

More specifically, the apparatus 40 for preventing foreign matter from adhering to the optical element includes a fixed ring 40a having one end portion which is detachably screwed concentrically with respect to the optical axis of the lens barrel into the well-known filter screw-in annular groove. A main body ring 40b connected to the other end of the fixed ring 40a concentrically and detachably with respect to the optical axis of the lens barrel, for example, by screwing; A rotary drive ring 40e, which is rotatably mounted concentrically with respect to the shaft, and a rotation support means 4 such as a ball bearing mechanism, for example, at a free end of the outer peripheral surface of the main body ring 40b.
And a filter holding ring 40f that is rotatably supported concentrically with respect to the optical axis of the lens barrel via the lens holder 1 and is driven to rotate by rotation of the rotation driving ring 40e. The filter holding ring 40f holds a filter 42 which is a kind of optical element arranged concentrically with respect to the optical axis of the lens barrel.

The rotary drive ring 40e is composed of two annular members 44a, 44 which can be divided from each other in a direction along the optical axis of the lens barrel.
4b. Two annular members 44a, 4
4b, an outer rim 46 formed concentrically with the optical axis of the lens barrel on the outer peripheral surface of the main body ring 40b from the direction along the optical axis of the lens barrel as shown in FIG. By being combined with each other so as to be sandwiched, it is concentric with the optical axis of the lens barrel in a state where the position in the direction along the optical axis of the lens barrel is regulated around the outer rim 46 on the outer peripheral surface of the main body ring 40b. It is rotatable.

A non-slip groove 48 for preventing the one annular member 44b from sliding in the circumferential direction is formed on the outer peripheral surface of the one annular member 44b adjacent to the filter holding ring 40f. An end face of the one annular member 44b adjacent to the filter holding ring 40f protrudes at a plurality of concentric circles with respect to the optical axis of the lens barrel in the same direction parallel to the optical axis of the lens barrel. A plurality of small gears 50 are rotatably held with respect to the rotation center shaft 49. The plurality of small gears 50 mesh with an external gear 52 formed concentrically with the optical axis of the lens barrel on the outer peripheral surface of the main body ring 40b at a position facing inward in the radial direction of the main body ring 40b. At the same time, at the position facing outward in the radial direction, the one annular member 4
The end face adjacent to 4b is meshed with an internal gear 54 formed concentrically with the optical axis of the lens barrel. And
The external gear 52 on the outer peripheral surface of the main body ring 40b, the internal gear 54 of the filter holding ring 40f, and the one ring of the rotary drive ring 40e interposed between the external gear 52 and the internal gear 54. The plurality of small gears 50 of the member 44b constitute a planetary gear mechanism.

In the device 40 for preventing foreign matter from adhering to an optical element having such a structure, when foreign matter such as dust or water droplets adheres to the external space exposed surface (outer surface) of the filter 42, the rotary drive ring 40e The one annular member 44
When the one annular member 44b is manually rotated on the outer peripheral surface of the main body ring 40b by gripping the non-slip groove 48 on the outer peripheral surface of the main ring 40b, the rotation is increased by the planetary gear mechanism and transmitted to the filter holding ring 40f. Filter holding ring 40f
Is driven to rotate at an increased speed. As a result, a centrifugal force acts on foreign substances such as dust and water droplets on the external space exposed surface (external surface) of the filter 42, and the centrifugal force causes the foreign substances to move outside the filter 42. It is brushed off from the exposed surface (outer surface).

As described above, since anything other than centrifugal force does not act on foreign matters such as dust and water droplets on the outer space exposed surface (outer surface) of the filter 42, the outer space exposed surface (outer surface) of the filter 42 ) Does not stain or damage the outer surface when removing the foreign matter. Then, the optical performance of the filter 42 is not affected. Further, even if the filter 42 is rotated during photographing or the filter 42 is kept rotating, a lens device (not shown) provided with the device 40 for preventing foreign matter from adhering to the optical element, An optical device such as a camera provided with a lens device that does not use the optical device can be fully utilized.

As described above, the action of removing the foreign matter from the outer space exposed surface (outer surface) of the filter 42 by using the centrifugal force is performed by the outer space exposed surface (outer surface) of the filter 42.
Has higher water repellency, it can be further enhanced. Making the outer space exposed surface (outer surface) of the filter 42 water-repellent can be performed, for example, by performing a water-repellent treatment on the outer space exposed surface (outer surface) of the filter 42.

A rotary drive source such as a motor is installed on the main body ring 40b, and the one annular member 44 is rotated by the rotary drive source via a torque transmitting means such as a gear mechanism.
b can also be rotated.

From the above description with reference to FIGS. 3A and 3B, the filter 42, which is a kind of optical element exposed to the external space in the above embodiment, is rotated around its own optical axis. It is apparent that the filter holding ring 40f, the main body ring 40b, and the rotation supporting means 41 between the filter holding ring 40f and the main body ring 40b constitute the rotatable holding means held as possible. From the above description, furthermore, the rotation driving means for rotating the filter holding ring 40f of the rotation holding means is provided with a rotation driving ring 40e to which a rotation force is inputted from the outside and a rotation force inputted to the rotation driving ring 40e. It is clear that the above-mentioned planetary gear mechanism transmitting to the filter holding ring 40f constitutes.

As a fourth embodiment according to the present invention, a rotary drive with a plurality of small gears 50 in the third embodiment described above with reference to FIGS. It is conceivable that the ring 40e, the external gear 52 on the outer peripheral surface of the main body ring 40b, and the internal gear 54 of the filter holding ring 40f are omitted.

The fourth embodiment has a simpler configuration, is easier to manufacture, and is less expensive than the third embodiment. Then, in order to remove foreign matters such as dust and water droplets on the outer space exposed surface (outer surface) of the filter 42 using centrifugal force, the outer peripheral surface of the filter holding ring 40f is directly grasped and the filter holding ring is manually operated. It is only necessary to rotate 40f on the outer peripheral surface of the main body ring 40b. In this case, the larger the mass of the filter holding ring 40f is, the greater the rotational inertia can be given to the filter holding ring 40f. Then, rotational energy is applied from the outside to rotate the top manually, and as a result of the high rotation, foreign matter can be sufficiently removed from the outer space exposed surface (outer surface) of the filter 42 by centrifugal force.

[0046]

As is clear from the above description,
In the device for preventing water droplets from adhering to an optical element according to the present invention, the optical apparatus having the same, and the lens apparatus having the same, the performance of the optical element may be adversely affected or the performance of the optical element may be adversely affected even if it is used many times The optical element can be fully utilized while removing foreign matter such as dust and water droplets adhered to the external space exposed surface (outer surface) of the optical element without lowering the optical element. An optical device such as a lens device using an optical system can be fully utilized.

[Brief description of the drawings]

FIG. 1 shows a lens device provided with a device for preventing foreign matter from adhering to an optical element according to a first embodiment of the present invention, which is combined with a camera body of a camera which is a kind of optical equipment using the lens device. It is a longitudinal cross-sectional view schematically shown in a state.

FIG. 2 shows a lens device provided with a device for preventing foreign matter from adhering to an optical element according to a second embodiment of the present invention, which is combined with a camera body of a camera which is a kind of optical equipment using the lens device. It is a longitudinal cross-sectional view schematically shown in a state.

FIG. 3A is a longitudinal sectional view schematically showing a device for preventing foreign matter from adhering to an optical element according to a third embodiment of the present invention; and FIG. 3B is a longitudinal sectional view of FIG. FIG. 2A is an exploded perspective view schematically showing the foreign matter adhesion preventing device for the optical element of FIG.

[Explanation of symbols]

 Reference Signs List 10 lens device 12 camera body 14 filter (optical element) 16 filter holding ring (rotation holding means) 18 filter connecting ring (rotation holding means) 20 rotation supporting means (rotation holding means) 22 internal gear (rotation driving means) 24 rotation Drive source (rotation driving means) 26 Gear speed increasing mechanism (rotation driving means) 26a Input gear (rotation driving means) 28 Output gear (rotation driving means) 32 Rotation driving source (rotation driving means) 32a Rotation force transmission shaft (rotation driving) Means) 40f Filter holding ring (rotation holding means) 40b Main body ring (rotation holding means) 40e Rotation driving ring (rotation driving means) 41 Rotation support means (rotation holding means) 42 Filter (optical element) 48 Internal gear (rotation driving) Means) 50 Small gear (rotation driving means) 54 External gear (rotation driving means)

Claims (5)

[Claims] 1. A rotation holding means for holding an optical element exposed to an external space rotatably around its own optical axis; and a rotation driving means for rotating the rotation holding means. For preventing foreign matter from adhering to optical elements. 2. An optical apparatus comprising: a rotation holding means for holding an optical element exposed to an external space rotatably around its own optical axis; and a rotation drive source for rotating the rotation holding means. An optical device comprising a device for preventing foreign matter from adhering to an optical element. 3. A lens device comprising: a rotation holding means for holding an optical element exposed to an external space rotatably around its own optical axis; and a rotation drive source for rotating the rotation holding means. A lens device comprising a device for preventing foreign matter from adhering to an optical element. 4. A rotation holding means for holding an optical element exposed to an external space rotatably around its own optical axis in a lens device detachably connected to a camera having a rotation drive source; A rotational force transmitting means for transmitting a rotational force from the rotational drive source to the rotational holding means when the lens device is connected to the camera; A lens device equipped with an adhesion prevention device. 5. The optical element according to claim 1, wherein a surface exposed to an external space of the optical element has water repellency. Lens device with device.