Patent ID: 7374352

Claim:
A light amount adjusting apparatus used in an image pickup apparatus, the light amount adjusting apparatus comprising: a base plate having an opening; a blade member movable within a range including a position where the blade member overlaps the opening in a light axis direction, for restricting an amount of a light passing through the opening by overlapping the opening; a plate member adjacent to the blade member and having a first cut portion different from the opening at a position where the plate member overlaps the blade member in the light axis direction in a state in which the blade member is at a predetermined position; and a cover member which is provided to sandwich the blade member in the optical axis direction with the plate member and in which a second cut portion is formed so that at least both whole portion of the opening and a part of the first cut portion locate within the second cut portion, wherein the blade member is a diaphragm blade for reducing the amount of light passing through the opening, wherein the plate member is a partition plate arranged between the diaphragm blade and a shutter blade for intercepting the light to pass through the opening, and wherein the cover member is a shutter cover to retain the diaphragm blade, the partition plate and the shutter blade not to be detached.