| 摘要 |
PURPOSE:To obtain a photoelectric transducing output which is not influenced by the image height of a projected image on a photodetector array by providing a lateral shift detection system focusing detector with an exit pupil splitting means consisting of plural fine exit pupil splitting optical systems. CONSTITUTION:The distance between the point 6-P of the position 6 of an exit pupil on an optical axis 7 and the center 11j-S between couples of photodetectors 11j-A and 11j-B is denoted as X, the distance between the exit pupil position and photodetector array is denoted as L0, and the distance between the mask 12 and the photodetector array 12 is denoted as (h). Further, the distance from the optical axis in the center 12j-S of the opening of the stripe mask is denoted as Y(X), and then Y(X)=X(1-h/L0). Furthermore, Ps=2P(1-h/L0), where Ps is the pitch of the opening of the stripe mask 12 and P is the constant pitch of the photodetector array. Consequently, pieces of luminous flux running in the centers of respective openings 12j are made incident to corresponding photodetectors equally. |
