To provide an optical quantity adjusting device which is made comparatively small in size, whose opening/closing operation is smoothly carried out without causing optical quantity unevenness due to the deformation of blades, and to provide an imaging apparatus and a projecting apparatus using the light quantity adjusting device.
The light quantity adjusting device is provided with a substrate having an optical-axis aperture, six or more n even-numbered blade members arranged around the optical-axis aperture at nearly equal intervals, and a supporting shaft arranged on the substrate so as to freely rotatably support the base ends of the blade members, and the blade members are arranged so that the adjacent edge parts are successively overlaid on top of one another like scales while making the leading ends face the optical-axis aperture. And the blade members arranged on the substrate are classified into two, the 1st blade is constituted of at least two blades which mutually overlap, each blade is freely rotatably supported so that the base end is taken as a a support shaft, and the blade leading end is positioned inside the aperture edge of the optical-axis aperture in a fully closed state. The 2nd blade member is constituted to have the number of blades which are overlaped each other, corresponding to the 1st blade member, and each blade of the 2nd blade member is a comparatively short blade so that the leading end of the blade is positioned outside the aperture edge of the optical-axis aperture in the whole open/closed area, and supported by the substrate.
| JPS63157134A | 1988-06-30 | |||
| JPS61256333A | 1986-11-13 |
Koji Mizuno
Toshiro Nakamura
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