| 摘要 |
PURPOSE:To obtain a focusing detector of good accuracy in focusing by providing a compound eye optical system behind the imaging optical system, and providing observing means such as an eyepiece that visualizes the image on a reimaging plane, an image pickup device or the like. CONSTITUTION:The image spot on an image plane S' by a focusing lens 1 is reimaged on a reimaging plane S'' by a compound eye optical system 5. In the stage of focusing, the image plane S' and a focus plane W0 coincide and therefore the reimaging plane S'' and the focus plane W'0 coincide but in the stage of nonfocusing, these faces do not coicide. An index such as cruciform of an adjusted visibility is provided on the position of the plane W'0. The image on the plane S' and the index are observed by the naked eye 7 through an eyepiece lens 6 or are observed with a TV monitor 4. Thus the focusing detector of good accuracy in focusing is obtained. |
