| 摘要 |
PURPOSE:To cope with the change of the focal distance of an image pickup lens with a phase type optical low-pass filter when the phase type optical low- pass filter is arranged in front of the image pickup lens and to collect a large amount of information for detecting focusing at the time of AF. CONSTITUTION:The device consists of an image pickup lens 20 with variable focal distance, a solid-state image pickup element 30 forming the optical image of an object via the lens 20, a phase type optical low-pass filter 10 provided freely rotatably in front of the lens 20, and a means rotating the filter 10 corresponding to the focal distance of the lens 20 for the purpose of eliminating a prescribed space frequency component equivalent to the picture element pitch of the element 30. A means which rotates the optical low-pass filter 10 by 90 deg. from the state where the space frequency component in the horizontal direction can be eliminated or retracted from the image pickup system when the focusing is detected by an AF detection circuit 36, and which restores the original state of the filter 10 when the image is picked up is provided. |
