| 摘要 |
PURPOSE:To realize focussing position detection even when a lens is at a great defocussing point with a simple constitution, by installing a light shielding member which focuses lights coming into a light receiver from an object and increasing the contrast value of the object. CONSTITUTION:When a contrast value obtained from detecting signals d1 and d3 is under an output condition which is able to detect a focusing position, light shielding members 12-1 and 12-2 are set to the opened condition, but, when the contrast value becomes another output condition which cannot detect a focussing position, the shielding members 12-1 and 12-2 are set to the closed condition and the contrast value is set to the output condition which can detect the focussing position. At the same time, a lens is moved and the shielding members 12-1 and 12-2 are again set to the opened condition. Since the contrast value of an object is raised in accordance with contrast signals to be used for detecting the focussing position in this way, the focussing position detection can be performed even when the lens is at a great defocussing point with a simple constitution. |
