| 摘要 |
PURPOSE:To obtain a proper focusing speed corresponding to photographic conditions by making a focusing speed fast if an object distance measurement range of switching is small when a video camera is operated on an automatic focus basis, and making the focusing speed faster than an automatic focusing speed when automatic focusing is selected in manual focusing mode. CONSTITUTION:An image of a subject 1 is recorded on a video tape through an image pickup lens 2, a CCD 4, etc. An AF interface 7, on the other hand, finds a focusing position by detecting a phase difference from diffracted light from a half-mirror 3 and controls a driving motor 10 through a control circuit 8 to move a lens 2. At this time, the circuit 8 is provided with a multi-stage distance measurement range changeover switch 11 and the focusing speed is made fast when the distance measurement range is narrow. Further, the circuit 8 is provided with an automatic/manual focusing switch 12 and when a one- punch automatic SW13 is turned on in manual focusing mode, focusing is performed faster than the automatic focusing. Consequently, the focusing is performed at the proper speed corresponding to the photographic conditions. |
