Patent ID: 6101030
Filing Date: 2000-08-08
Classification: G02B

Abstract:
A real image mode variable magnification finder, comprising:an objective system with positive refracting power;an image erecting optical system constructed and arranged to erect an object image formed by said objective system; andan eyepiece system with positive refracting power,said objective system comprising, in order from an object side;a first lens unit with negative refracting power;a second lens unit with positive refracting power; anda third lens unit with positive refracting power,a space between said first lens unit and said second lens unit and a space between said second lens unit and said third lens unit being changed when a magnification of said finder is changed in a range from a wide-angle position to a telephoto position,said image erecting optical system having a first prism and a second prism so that a field frame is interposed between said first prism and said second prism, andsaid finder satisfying the following conditions:3.5 mm.sup.-1 <(m/f.sub.e.sup.2).times.1000<11 mm.sup.-1where m is a distance from a field frame-side vertex of said first prism to said field frame and f.sub.e is a focal length of said eyepiece system.