Focus detecting device for camera

Abstract

Abstract PURPOSE:To facilitate size reduction and to position plural image forming lens couples and photodetecting element arrays with high accuracy by constituting an image re-forming lens system as an integrally molded member consisting of plano-convex lenses which all have the same radius of curvature. CONSTITUTION:A visual field mask FM is arranged on the expected image formation surface FP of a photographic lens TL and pieces of passing luminous flux of respective rectangular opening parts E0-E02 of the mask FM are converged by condenser lenses L0-L02. An image re-forming lens plate L is equipped with couples of image re-forming lenses L1 and L2, L3 and L4, and L5 and L6 and an aperture mask AM is in contact right before the plate L. Line sensors P01 and P02 include photodetecting element arrays. Thus, the three couples of image reforming lenses L1-L6 are all plano-convex lenses which are equal in radius of curvature and integrated moldings. Consequently, the position accuracy among the lenses L1-L6 is improved greatly.

Inventors

• 👤 Toshihiko Karasaki
• 👤 敏彦 唐崎

Bibliographic Details