Title:
LIGHT QUANTITY ADJUSTMENT DEVICE AND OPTICAL INSTRUMENT
Document Type and Number:
Japanese Patent JP2023134146
Kind Code:
A
Abstract:
To provide a light quantity adjustment device that can reduce the warp of a plurality of light quantity adjustment blades when the light quantity adjustment blades are closed.SOLUTION: In a light quantity adjustment device according to the present invention, each of a plurality of light quantity adjustment blades overlaps another light quantity adjustment blade to form a light passage opening, and the plurality of light quantity adjustment blades rotate to change the size of the light passage opening. Each of the plurality of light quantity adjustment blades has a first portion that has a constant thickness, and a second portion that is formed to be reduced in thickness from the first portion toward an end edge part that forms the edge of the light passage opening. With the plurality of light quantity adjustment blades overlapping each other in a light passage direction in a minimum aperture state of the light quantity adjustment device, the area of overlapping of the second portions of the adjacent blades is larger than the area of overlapping of the first portions.SELECTED DRAWING: Figure 3
Inventors:
YAMAMOTO KENTA
NAKAWAKI SHINYA
NAKAWAKI SHINYA
Application Number:
JP2022039508A
Publication Date:
September 27, 2023
Filing Date:
March 14, 2022
Export Citation:
Assignee:
CANON DENSHI KK
International Classes:
G03B9/02; G03B9/06
Attorney, Agent or Firm:
Patent Attorney Corporation Otsuka International Patent Office