PURPOSE: To simplify the constitution and reduce noise components by providing a focus deflecting element in an optical system in the picture reading method of a solid-state image pickup element.

CONSTITUTION: An image pickup part 2 consists of an optical system 6 provided in the front end part of a lens barrel 4 and a CCD 8 arranged in the focusing surface of the optical system 6, and the optical system 6 consists of a taking lens 10, which focuses an object, and a transparent parallel plane plate 12 which deflects the focus position. This parallel plane plate 12 is rotated interruptedly, and the image focused on the CCD 8 is rotated by an eccentric quantity of about a half of the picture element pitch, and the image is read when the CCD 8 comes to upper, lower, left, and right parts, thereby obtaining the number of sampling picture element equivalent to a high-density zigzag arrangement.