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:
Jun. 16, 1992
Filed:
Mar. 12, 1990
Omron Corporation, Kyoto, JP;
Abstract
An optical element having a substrate and a composite grating pattern formed thereon. The pattern is constituted with two different kinds of grating patterns superimposed on the substrate. When one of the two kinds of grating patterns is formed in a Fresnel lens pattern, a light focusing or collimating function (i.e. a lens function) is implemented. When the other pattern is formed in an equally separated linear grating pattern, the optical element develops the lens function and a function to diffract lights through the linear grating. When one of the two kinds of grating patterns is formed in a Fresnel lens pattern and the other pattern is implemented in an unequally separated linear grating pattern, a lens function to focus lights onto a point and a cylindrical lens function to focus lights in a linear contour are obtained. Consequently, when parallel lights are incident to the optical element, there occurs astigmatism.