Light quantity adjustment apparatus and image pickup apparatus

Abstract

A light quantity adjustment apparatus includes a pair of substrates having a light-path aperture; a plurality of diaphragm blades disposed between the pair of substrates; a driving ring that opens and closes the plurality of diaphragm blades; and a driving device. The plurality of diaphragm blades is supported by the substrate via a first guide plate made of a resin film. The substrate and the first guide plate are provided with guide grooves fitted into protrusions formed in the plurality of diaphragm blades to guide the blades. Guide grooves of the substrate are formed of concave grooves. Guide grooves of the first guide plate are formed of through holes. The through holes of the first guide plate have a narrower width than the concave grooves of the substrate to engage in the protrusions of the diaphragm blades and to guide the diaphragm blades in the open and close direction.

Description

technical field [0001] The present invention relates to a light quantity adjustment device for adjusting light quantity such as photography light quantity and projection light quantity, which is incorporated in imaging devices such as video cameras and still cameras, or other projection devices such as projectors. Background technique [0002] Generally, this kind of light quantity adjustment device is known as follows. A substrate with an optical axis opening is arranged on the photographing optical path (or projection optical path), and a plurality of light quantity adjustment blades are arranged on the substrate in a freely openable and closable manner. The aperture can be adjusted with a large aperture or a small aperture to adjust the amount of light. [0003] For example, Patent Document 1 discloses an iris diaphragm device in which a plurality of blades are arranged around an optical axis opening formed on a substrate to open and close the optical path aperture in a s...

AI Technical Summary

Problems solved by technology

[0029] In this case, if the notched recessed portion of the drive ring is formed outside the opening and closing locus of the vane, the vane can be avoided, but the diameter of the drive ring becomes larger to the outside of the locus of movement of the vane, and the sliding friction with the vane increases. At the same time, it leads to the enlargement of the aperture device, which leads to the problem that the lens barrel of the imaging device installed therein becomes larger.

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