JP2007304419A5 - - Google Patents

Claims (5)

In the light amount adjusting device which has a plurality of blade members and changes the size of the opening through which the light beams pass by rotating the plurality of blade members,
The arcuate inner edges of the plurality of blade members that are involved in the formation of the openings are a root inner edge near the rotation axis of the blade member, a tip inner edge far from the rotation axis, and an intermediate inner edge between the two A tip boundary inner edge connected from the tip inner edge to an inner edge not involved in the formation of the aperture opening, and a root boundary inner edge connected from the root inner edge to the inner edge not involved in the formation of the aperture opening. A light amount adjusting device characterized by being formed. The shape of the opening is formed by a forming edge including the intermediate inner edge from the vicinity of the opening to the small aperture, and an arcuate line segment from the intermediate inner edge to the tip boundary inner edge is equal to or larger than the intermediate inner edge arc radius . An arcuate line group that is composed of a line group of curvature radii from the intermediate inner edge part to a root boundary inner edge part is configured of a line segment group of a curvature radius that is equal to or greater than the intermediate inner edge arc radius;
When the opening changes from the vicinity of the opening toward the small aperture, the inner edge part that is involved in the formation of the opening gradually decreases from the whole of the five inner edge parts to the base inner edge part side from the tip inner edge part side. The light amount adjusting device according to claim 1, wherein the light amount adjusting device changes.   Each of the other inner edges excluding the intermediate inner edge is formed so as to move away from the intermediate inner edge as the distance from the intermediate inner edge increases. The light quantity adjusting device according to claim 1, wherein the light amount adjusting device has an arc radius larger than the arc radius.   A lens device comprising the light amount adjusting device according to claim 1.   An image pickup apparatus comprising the light amount adjusting device according to claim 1.