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. 06, 2018
Filed:
Aug. 31, 2016
Hamamatsu Photonics K.k., Hamamatsu-shi, Shizuoka, JP;
Akio Ito, Hamamatsu, JP;
Tatsuo Dougakiuchi, Hamamatsu, JP;
Kazuue Fujita, Hamamatsu, JP;
Tadataka Edamura, Hamamatsu, JP;
HAMAMATSU PHOTONICS K.K., Hamamatsu-shi, Shizuoka, JP;
Abstract
A quantum cascade laser is configured with a semiconductor substrate, and an active layer having a multistage lamination of emission layers and injection layers. The active layer is configured to be capable of generating first pump light of a frequency ωand second pump light of a frequency ω, and to generate output light of a difference frequency ω by difference frequency generation. An external diffraction grating is provided for generating the first pump light, outside an element structure portion including the active layer, and an internal diffraction grating is provided for generating the second pump light, inside the element structure portion. The frequency ωis set to be fixed to a frequency not coincident with a gain peak, and the frequency ωis set to be variable to a frequency different from the frequency ω