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:
Mar. 10, 2026
Filed:
Mar. 25, 2021
Hamamatsu Photonics K.k., Hamamatsu, JP;
Atsushi Sugiyama, Hamamatsu, JP;
Kousuke Shibata, Hamamatsu, JP;
Kazuue Fujita, Hamamatsu, JP;
Masahiro Hitaka, Hamamatsu, JP;
HAMAMATSU PHOTONICS K.K., Hamamatsu, JP;
Abstract
A quantum cascade laser element includes: a semiconductor substrate; a semiconductor laminate having a first end surface and a second end surface; a first electrode; a second electrode; and an anti-reflection film formed on the first end surface. The semiconductor laminate is configured to oscillate laser light having a center wavelength of 7.5 μm or more. The anti-reflection film includes an insulating film being a CeOfilm formed on the first end surface, a first refractive index film being a YFfilm or a CeFfilm disposed on a side opposite the first end surface with respect to the insulating film, and a second refractive index film formed on the first refractive index film on a side opposite the first end surface with respect to the first refractive index film and having a refractive index of larger than 1.8.