One of the aspects of the disclosure relates to an optical filter apparatus and an image pickup apparatus.
An image pickup apparatus including a camera mount with a short flange focal length distance is demanded to be thin in an optical axis direction of an optical filter apparatus located between a mount surface and an image sensor. An optical filter apparatus including a plurality of optical filters particularly needs to be made thin.
Japanese Patent Laid-Open No. (“JP”) 2020-134889 discloses an optical filter apparatus in which a position of a guide bar that holds a frame of an optical filter is shifted in order to reduce the thickness in the optical axis direction.
The optical filter apparatus disclosed in JP 2020-134889 is thin in the optical axis direction, but this thinning scheme is insufficient depending on the structure of the image pickup apparatus.
The disclosure provides an optical filter apparatus that is thinner in an optical axis direction.
An optical filter apparatus according to one aspect of the disclosure includes a first optical filter unit, a first holding frame that holds the first optical filter unit, a first guide bar and a second guide bar that movably support the first holding frame, a second optical filter unit disposed approximately parallel to the first optical filter unit, a second holding frame that holds the second optical filter unit, a third guide bar and a fourth guide bar that movably support the second holding frame, a first housing that covers the first holding frame, and a second housing that covers the second holding frame. The first holding frame is sandwiched between the first housing and one of the first guide bar and the second guide bar. The second holding frame is sandwiched between the second housing and one of the third guide bar and the fourth guide bar. An image pickup apparatus including the above optical filter apparatus constitutes another aspect of the disclosure.
Further features of the disclosure will become apparent from the following description of exemplary embodiments with reference to the attached drawings.
Referring now to the accompanying drawings, a detailed description will be given of embodiments according to the disclosure.
Referring now to
Referring now to
The optical filter apparatus 1 includes a first housing 10, a first unit 20, a second unit 30, and a second housing 40, as illustrated in
The first optical filter 202 and the second optical filter 203 are held by a first holding frame 201. The first holding frame 201 is slidable along a first guide bar 204 and a second guide bar 205 extending in directions orthogonal to the optical axis X of the image sensor C so that the first optical filter 202 and the second optical filter 203 are switched. The third optical filter 302 and the fourth optical filter 303 are held by a second holding frame 301. The second holding frame 301 is slidable along a third guide bar 304 and a fourth guide bar 305 extending in the directions orthogonal to the optical axis X of the image sensor C so that the third optical filter 302 and the fourth optical filter 303 are switched.
The first holding frame 201 is supported so as to cover the entire circumference of the first guide bar 204. The second holding frame 301 is supported so as to cover the entire circumference of the third guide bar 304. A portion of the first holding frame that covers the entire circumference of the first guide bar, and a portion of the second holding frame that covers the entire circumference of the third guide bar are located on opposite sides with respect to the optical axis X of the optical filter apparatus. This configuration can achieve a thinner structure of the optical filter apparatus. The first guide bar 204 is supported by a first convex portion 101 and a second convex portion 102 of the first housing 10 and a first concave portion 401 and the second concave portion 402 of the second housing 40. The second guide bar 205 is supported by convex portions 103 and 104 of the first housing 10 and concave portions 403 and 404 of the second housing 40. The third guide bar 304 is supported by convex portions 105 and 106 of the first housing 10 and concave portions 405 and 406 of the second housing 40. The fourth guide bar 305 is supported by convex portions 107 and 108 of the first housing 10 and concave portions 407 and 408 of the second housing 40.
An end (first end) 201a of the first holding frame 201 is sandwiched between the second guide bar 205 and the first housing 10. An end (second end) 301a of the second holding frame 301 is sandwiched between the fourth guide bar 305 and the second housing 40. The first guide bar 204, the second guide bar 205, the third guide bar 304, and the fourth guide bar 305 are disposed at positions that approximately coincide with each other in the optical axis direction (X direction). The first guide bar 204 is disposed outside the fourth guide bar 305 with respect to the first holding frame 201. The third guide bar 304 is disposed outside the second guide bar 205 with respect to the second holding frame 301. Thereby, the optical filter apparatus 1 can be thin in the optical axis direction (X direction).
A driving unit 50 (see
The first housing 10 has a convex portion (first housing convex portion) 109 facing the second guide bar 205. The first holding frame 201 includes a convex portion (first convex portion) 201b and a convex portion (third convex portion) 201c on the end 201a. The convex portion 201c faces the second guide bar 205. In a case where the first holding frame 201 is driven, the convex portion 109 of the first housing 10 and the convex portion 201b of the first holding frame 201 slide relative to each other, and the convex portion 201c of the first holding frame 201 and the second guide bar 205 slide relative to each other. The second housing 40 has a convex portion (second housing convex portion) 409 facing the fourth guide bar 305. The second holding frame 301 has a convex portion (fourth convex portion) 301b and a convex portion (second convex portion) 301c on the end 301a. The convex portion 301b faces the fourth guide bar 305. In a case where the second holding frame 301 is driven, the convex portion 409 of the second housing 40 and the convex portion 301c of the second holding frame 301 slide relative to each other, and the convex portion 301b of the second holding frame 301 and the fourth guide bar 305 slide relative to each other.
As described above, in the optical filter apparatus 1, the first holding frame 201 is slidably sandwiched between the first housing 10 and the first guide bar 204 or the second guide bar 205, and the second holding frame 301 is slidably sandwiched between the second housing 40 and the third guide bar 304 or the fourth guide bar 305. The first holding frame 201 may include a first end (end 201a) located on the side opposite to the first guide bar 204 with respect to the first optical filter unit, and is slidably sandwiched between the first housing 10 and the second guide bar 205 at the first end. The second holding frame 301 may include a second end (end 301a) located on the side opposite to the third guide bar 304 with respect to the second optical filter unit, and is slidably sandwiched between the second housing 40 and the fourth guide bar 305 at the second end.
This embodiment can reduce the thickness in the optical axis direction (X direction) in the optical filter apparatus that can switch between a plurality of optical filters. In this embodiment, the optical filter is, for example, a neutral density filter, an infrared (IR) cut filter, a polarization filter, dummy glass, or the like, but is not limited to this example. In this embodiment, the number of optical filters and the number of combination types of the optical filters can be arbitrarily set. In this embodiment, the material, shape, size, form, number, location, etc. of each component of the optical filter apparatus can be properly changed. This embodiment can provide an optical filter apparatus and an image pickup apparatus, each of which is thin in the optical axis direction.
The driving unit 50 includes a first driving unit configured to drive the first holding frame 201 and a second driving unit configured to drive the second holding frame 301. The second guide bar 205 is farther from the first driving unit than the first guide bar 204, and the fourth guide bar 305 is farther from the second driving unit than the third guide bar 304. This configuration can provide stable driving.
While the disclosure has been described with reference to exemplary embodiments, it is to be understood that the disclosure is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.
This application claims the benefit of Japanese Patent Application No. 2022-017127, filed on Feb. 7, 2022, which is hereby incorporated by reference herein in its entirety.
Number | Date | Country | Kind |
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2022-017127 | Feb 2022 | JP | national |