LIGHT-AMOUNT ADJUSTMENT DEVICE AND IMAGING DEVICE

• Main Author: KAWAKUBO NAOKI
• Format: Patent
• Language: English; Japanese
• Published: 24.11.2017
• Subjects: ACCESSORIES THEREFOR; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USINGWAVES OTHER THAN OPTICAL WAVES; APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FORPROJECTING OR VIEWING THEM; CINEMATOGRAPHY; ELECTROGRAPHY; HOLOGRAPHY; PHOTOGRAPHY; PHYSICS

PROBLEM TO BE SOLVED: To provide a light-amount adjustment device that is downsized and implements stable operations.SOLUTION: A light-amount adjustment device has: a base member that has a fixed opening through which light passes; a plurality of aperture blades that are circularly arranged in a circumferential direction of the fixed opening and form a variable opening through which the light passes; a plate member that is placed on a side opposite to the base member with respect to the aperture blades, and has a plurality of cam grooves; a drive ring that rotates in the circumferential direction of the fixed opening with respect to the base member to transmit driving force to a drive pin, and thereby makes the plurality of aperture baldes rotate so as to vary a size of the variable opening; and a drive source that has a connection point with the drive ring to make the drive ring rotatably drive. A position where the connection point between the drive ring and the drive source is projected in an optical axis direction is included in an in-plane of a movable range of the aperture blades.SELECTED DRAWING: Figure 1 【課題】小型で安定動作をする光量調節装置を提供する。【解決手段】光が通過する固定開口を有するベース部材と、固定開口の周方向に環状に複数配置されて光が通過する可変開口を形成する絞り羽根と、絞り羽根に対してベース部材とは反対側に配置され、複数のカム溝を有する板部材と、ベース部材に対して固定開口の周方向に回転して駆動ピンに駆動力を伝達することで、可変開口の大きさを変化させるように複数の前記絞り羽根を回動させる駆動リングと、駆動リングと接続点を持ち回転駆動させる駆動源と、を有し、絞り羽根の可動範囲面内に駆動リングと駆動源の接続点を光軸方向に投影した位置が含まれている。【選択図】 図１