| 摘要 |
PROBLEM TO BE SOLVED: To prevent image quality from deteriorating due to diffraction, even if an image pickup element with a smaller screen size in an exposure control device where the aperture formed by a plurality of aperture blades moving straight into reverse directions to each other is covered by an ND filter. SOLUTION: This image pickup device has an exposure control device 1, that regulates a quantity of luminous flux made incident onto a photographing lens system 91, the exposure control device has an aperture where an aperture 15 is formed by aperture blades 2, 3 moving in opposite directions to each other on a plane orthogonal to an optical axis and also has ND filters 21a, 21b, 21c, 21d with at least two kinds of different transmission factors. When the aperture open state transits to a limit state of the transmitted luminous quantity, the aperture area is limited by the aperture blades from the open aperture to a prescribed opening, and the NF filters are entered into the aperture in the order of higher transmissivities, while keeping the prescribed opening.
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