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:
Dec. 02, 2025
Filed:
Jan. 14, 2021
Hitachi High-tech Corporation, Tokyo, JP;
Takanori Aono, Tokyo, JP;
Yoshisada Ebata, Tokyo, JP;
Kenta Yaegashi, Tokyo, JP;
Shigeru Matsui, Tokyo, JP;
Isao Uchida, Tokyo, JP;
Jiro Yamamoto, Tokyo, JP;
Hitachi High-Tech Corporation, Tokyo, JP;
Abstract
The present invention provides a concave diffraction grating and an optical device using the concave diffraction grating, the concave diffraction grating being capable of preventing deformation of a reflection film due to the influence of temperature, and preventing deterioration in optical characteristic due to temperature. This concave diffraction grating is provided with: a reflection film () having a plurality of grating grooves (); a holding film () comprising metal and having one surface on which the reflection film () is provided; a concave substrate () having a concave surface (); and an affixing layer () provided between the concave surface () and the other surface of the holding film (), and affixing the holding film () and the reflection film () to the concave substrate ().