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:
May. 22, 2001
Filed:
Dec. 01, 1998
Seiji Shimizu, Hachioji, JP;
Olympus Optical Co., Ltd., Tokyo, JP;
Abstract
A photographic optical system greatly improved in chromatic aberration and capable of providing high image quality with a compact, lightweight and low-cost arrangement having a minimal number of constituent elements. The optical system has a negative lens placed closest to the image side thereof, and a positive lens, a negative lens and a positive lens, which are placed in order from the object side of the optical system on the object side of the negative lens closest to the image side. The negative lens closest to the image side satisfies the following conditions: 75.0≦&ngr;,and 0.8≦SG≦2.2, where &ngr;,and SG are the Abbe's number and lens specific gravity (g/cm,) of the negative lens closest to the image side.