Finder optical system
AssigneeOlympus Optical Co., Ltd.
InventorsYuji Miyauchi, Shinichi Yoshii, Tatsuru Kanamori
Life of this patent
Estimating the term…
Abstract
A finder optical system including an objective having a positive refractive power, an image erecting optical member for erecting an image formed by the objective, and an eyepiece for allowing observation of the image formed by the objective and erected by the image erecting optical member. The objective consists of a first positive lens component and a second negative lens component, or a single lens having a convex surface on the object side. This finder optical system has a simple composition, a compact external design and a relatively wide field angle.
Claims4
A finder optical system comprising:
- an objective including a first positive lens component and a second negative lens component, an image erecting optical system for erecting an image formed by said objective, and an eyepiece for allowing observation of the image formed by said objective and erected by said image erecting optical system;
- said finder optical system satisfying the following condition:
- 0.03<.vertline.f.sub.p /f.sub.n .vertline.<0.4
- wherein the reference symbol f.sub.p represents the focal length of said first lens component and the reference symbol f.sub.n designates the focal length of said second lens component.
A finder optical system comprising an objective consisting of a single positive lens having a convex surface on the object side, an image erecting optical system for erecting an image formed by said objective, and an eyepiece for allowing observation of the image formed by said objective and erected by said image erecting optical system.
Dependencies are inferred from the claim text.