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. 21, 2022
Filed:
Mar. 19, 2018
Dai Nippon Printing Co., Ltd., Tokyo, JP;
Nobuhito Toyama, Tokyo, JP;
DAI NIPPON PRINTING CO., LTD., Tokyo, JP;
Abstract
A diffractive optical element capable of further reducing zero-order diffraction light includes a diffraction layer including: a high refractive index part in which a plurality of projections are arranged side by side in a cross-sectional shape; and a low refractive index part that has a lower refractive index than the high refractive index part and that includes a recess formed at least between the projections. The projections have a sawtooth shape or a shape that imitates a sawtooth shape by a multi-stage outline shape. An inclined plane that is inclined with respect to a sheet surface of the diffractive optical element, which has a sawtooth shape or a sawtooth shape imitated by a multi-stage outline shape, has a concave curved plane that is concave toward the projections.