Patent Number: 6,252,729

Title: Real image type finder optical system

Abstract: A real image type finder optical system includes, in order from the object side, an objective optical system, a first prism, a second prism, and an eyepiece lens. The first prism includes a first face as an entrance surface confronting the exit plane of the objective optical system, a second face making an angle of 22.5.degree. with respect to this first face and a third face for transmitting the finder optical axis bent in order by the second face and the first face. The second prism includes a first face as an entrance surface confronting the third face of the first prism with a space therebetween, a second face opposed to the first face so as to bend the finder optical axis toward the object side within a horizontal plane, a third face for turning the finder optical axis bent in order by the second face and the first face to a direction generally coaxial with the eyepiece lens and a fourth face for transmitting the optical axis turned from the third face. The eyepiece lens confronts the fourth face of the second prism so as to be generally coaxial with the finder optical axis passing through the second prism.

Inventors: Kanai; Moriyasu (Tokyo, JP)

Assignee: Asahi Kogaku Kogyo Kabushiki Kaisha

International Classification: G03B 19/12 (20060101); G03B 013/06 (); G02B 005/04 ()

Expiration Date: 06/26/2018