MAGNIFICATION CONVERSION TYPE REVERSE GALILEAN FINDER

摘要

PURPOSE:To obtain a magnification conversion type reverse Galilean finder reduced at its size and compensated at respective aberrations efficiently while keeping the moving distance of a lens due to the conversion of magnification at a small value and a space on a eyepiece side at a large value by satisfying an objective lens with specific conditions. CONSTITUTION:It is defined that the focal distance of an objective lens L1 for low magnification is f1, the focal distance of a positive lens component La added to the lens L1 is fa, the focal distance of a negative lens component Lc on the eyepiece side out of an objective lens L2 is fc, the shape factor of the lens component La is Q1 and the shape factor of the component Lc is Qc. When the focal distances f1, fa, fc and the shape factors Q1, Qc are satisfied with the conditions shown by the inequality, aberrations at respective magnification states of the finder to be switched at its magnification can be efficiently corrected.