| 摘要 |
PURPOSE:To raise the focusing accuracy even in case the intensity of illumination of an object to be photographed is low by generating an optical output corresponding to an infrared optical image and a visible optical image of the object to be photographed, and generating a control signal for indicating a focused position of a photographic optical system to the object to be photographed. CONSTITUTION:An image of an object to be photographed is formed on photodetectors 9a, 9b through focusing optical system 10a, 10b. An operating part 14 receives an output signal of the elements 9a, 9b, and drives an image pickup optical system 7. As the image pickup optical system is driven, an image formed position of the image of the object to be photographed on the photodetectors 9a, 9b approaches a focused state. When the outputs of the photodetectors 9a, 9b are balanced, a signal of a driving stop is outputted from the operating part 14, and the focusing work is completed. By irradiating the object to be photographed by an infrared ray from a projecting part 8, it is possible to execute the focusing whose accuracy does not exert influence on the intensity of illumination of the object to be photographed. In this way, even in a state that the intensity of the object to be photographed is low, the focusing can be executed without dropping the focusing accuracy. |
