The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 13, 2001
Filed:
Oct. 20, 1999
Olympus Optical Co., LTD, Tokyo, JP;
Abstract
A viewing optical system and an image-forming optical system, in which an intermediate image is formed once and two decentered prisms, i.e. first and second prisms, are arranged to correct each other's decentration aberrations, thereby attaining a wide viewing field angle and a short focal length. The second prism is placed closer to the image side than the first prism and has four optical surfaces, of which a first surface is an entrance surface, second and third surfaces are reflecting surfaces, and a fourth surface is an exit surface. In the second prism, an optical path crosses itself. At least one of the second and third surfaces has a rotationally asymmetric surface configuration that gives a power to a light beam and corrects aberrations due to decentration. The first prism has a reflecting surface, an entrance surface, and an exit surface. The reflecting surface has a rotationally asymmetric surface configuration that gives a power to a light beam and corrects aberrations due to decentration. An intermediate image surface is formed between the first surface of the first prism and the exit surface of the second prism.