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:
Feb. 03, 1976
Filed:
Nov. 19, 1973
Applicant:
Inventors:
Hideo Ikeda, Kamakura, JA;
Hideki Akasaka, Kawasaki, JA;
Assignee:
Nippon Kogaku K.K., Tokyo, JA;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G02B / ;
U.S. Cl.
CPC ...
350-1 ; 350164 ;
Abstract
A three-layer anti-reflection film for ultraviolet range comprises a first layer having a refractive index n.sub.1 determined so as to provide a great dispersion effect in the peripheral range, a second layer having a refractive index n.sub.2, and a third layer having a refractive index n.sub.1. The three layers are arranged symmetrically. The first and third layers are provided with an asymmetry so that an intended refractive index n* for the ultraviolet range from 200m.mu. to 400m.mu. may be obtained. The film has a predetermined optical thickness.