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:
Jul. 06, 2004
Filed:
May. 10, 2000
Applicant:
Inventor:
Takehiko Nakai, Kawasaki, JP;
Assignee:
Canon Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G02B 5/18 ;
U.S. Cl.
CPC ...
G02B 5/18 ;
Abstract
In a diffractive optical element, which is formed by laminating at least three layers of diffraction gratings made of at least three kinds of materials which differ in dispersion, at least three design wavelengths are set.