| 摘要 |
PROBLEM TO BE SOLVED: To provide a camera filter unit with reduced dimensions of a filter frame for holding an optical filter in an optical axis direction. SOLUTION: The camera filter unit 1 includes the filter frame 2, a filter-holding ring 3 and the optical filter 4. The optical filter 4 is fixed to an internal side of the filter-holding ring 3 while being held from the front and the rear between a protuberance 31 formed in the filter-holding ring 3 and a caulking part 33a. The filter-holding ring 3 is fixed to the internal side of the filter frame 2 by a ring-side male thread 32 on an outer peripheral surface which is screwed into a female thread 22 on an inner peripheral surface of the filter frame 2. The filter frame 2, the filter-holding ring 3 for fixing the optical filter 4 to the filter frame 2 and the optical filter 4 are arranged concentrically, thereby the front-and-rear dimension of the filter frame 2 can be made smaller than when the filter-holding ring 3 and the optical filter 4 are arranged while being not exposed from the filter frame 2. COPYRIGHT: (C)2010,JPO&INPIT |
