| 摘要 |
PURPOSE:To calculate the absolute distance of an object and projecting magnification before a focusing state is attained by calculating the intended feeding quantity to focus a lens based on the feeding quantity of a projecting lens and the deviation and the deviating direction of focus. CONSTITUTION:An output signal from a deviation information detection means 1 for detecting the deviating direction and the deviation of the image-formation surface of object light passing through the projecting lens 6 from a film surface in an optical axis direction is converted into a signal showing the deviating direction and the deviation of a focus group by a focus group deviation information decision means 3 for operating and deciding the driving quantity of the photographing lens 6 to the focusing position of the focus group based on the information on the deviating direction and the deviation of the focus being the output signal from the means 1. Then, the feeding position of the focus group where the focusing is intended is obtained based on the current feeding position of the focus group and the information on the deviating direction and the deviation of the focus group and the information of the object distance is operated and outputted based on the information on the focusing intended position of the focus group. Thus, the information on the object distance and the photographing magnification, etc., are easily and accurately obtained before performing a focusing action. |
