| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an iris device that can perform control so that a movement amount of a diaphragm blade with respect to a rotation angle of a lever holding the diaphragm blade in an area having a stop-down amount of the diaphragm blade less than a predetermined value is made smaller than those in other areas without exerting a force load to the diaphragm blade.SOLUTION: The iris device is configured to enable control so that a movement amount of a first engagement part 152 and a second engagement part 142a with respect to a rotation angle of a lever 140 extremely decreases in the vicinity of a closing state position (5). Thereby, a movement amount of a first diaphragm blade 120 and a second diaphragm blade 130 in a direction almost orthogonal to an optical axis can be extremely reduced in the vicinity of the closing state position (5). Thus, upon photographing, in particular, a subject of high luminance, a control of a diaphragm aperture diameter is made easy and quick.</p> |
