To provide an image pickup apparatus capable of preventing deterioration in an image quality and simplifying an aperture control even in a configuration where an aperture stop diameter should be made larger than a wide end according to a change in a focal length for retaining a constant F value.
When a focal length in imaging is less than middle B, a microcomputer 150 defines, despite the focal length, the maximal value of an aperture stop diameter of an aperture mechanism 102 used in imaging as an aperture stop diameter Φ1 corresponding to a minimal F value when the focal length is wide end A and, when the focal length in imaging is middle B or more, changes it according to the focal length within a range of less than the opening stop diameter Φ1.
JP2007033903A | 2007-02-08 | |||
JP2006208618A | 2006-08-10 | |||
JPH11258652A | 1999-09-24 | |||
JP2008187617A | 2008-08-14 | |||
JP2007033903A | 2007-02-08 | |||
JP2006208618A | 2006-08-10 |
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