| 摘要 |
PURPOSE:To make it possible to perform automatic focusing operation rapidly and stably by driving an image forming optical system based on a defocusing amount and controlling the drive of the image forming optical system based on information on an image surface moving speed so that the system may follow up the movement of the object from just after the object is caught by the image forming optical system. CONSTITUTION:The timing of starting and ending charge storage is transmitted to a control means 109 by a focus detecting means 104 for detecting the focusing state of a photographic lens 101. A period from the end of the charge storage and the state of the succeeding charge storage is applied to charge transfer and the calculation of the defocusing amount. The image surface moving speed of the image forming optical system on the image surface position accompanying the movement of the object is calculated based on plural calculated defocusing amounts, the amount due to the movement of the image forming optical system and a prescribed time. The image forming optical system is controlled so as to be driven to a target position which is obtained based on the defocusing amount and the image surface moving speed, and after the image forming optical system reaches the target position, the drive of the image forming optical system is controlled based on the image surface moving speed so that the system may follow up the movement of the object. |
