| 摘要 |
In an aperture stop mechanism 10, two aperture blades 14 and 16 are arranged so as to overlap each other and form a single light passage opening 50 into which light utilized in imaging is introduced with the respective edge portions of the two aperture blades 14 and 16. A drive mechanism 22 drives the two aperture blades 14 and 16 in directions different from each other, whereby the aperture area of the light passage opening 50 is changed within a predetermined range. When the two aperture blades 14 and 16 are located at a minimum aperture position where the aperture area of the light passage opening 50 is minimum within the predetermined range, the two aperture blades 14 and 16 are provided so that the single light passage opening 50 surrounded by boundaries including eight straight lines is constituted of the respective edge portions of the two aperture blades 14 and 16. |
