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:
Jan. 27, 1976
Filed:
Sep. 21, 1973
Applicant:
Inventors:
Susumu Itoh, Tokyo, JA;
Keijiro Nishida, Kanagawa, JA;
Osamu Kamiya, Tokyo, JA;
Nobuyuki Sekimura, Yokohama, JA;
Assignee:
Canon Kabushiki Kaisha, , JA;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G02B / ;
U.S. Cl.
CPC ...
350164 ; 427166 ; 428432 ; 428539 ; 428213 ;
Abstract
Three-layer anti-reflection coatings consisting of first, second and third layers, respectively positioned from a glass base plate. The optical film thickness of the first layer and the second layer is one-half of a designed wavelength while that of the third layer is one-fourth of the same. And the relationship among the refractive index of each layer is second layer (n.sub.2) glass (n.sub.g) first layer (n.sub.1) third layer (n.sub.3). The first layer is made of a mixture of Al.sub.2 O.sub.3 and ZrO.sub.2.