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:
Jan. 02, 2018
Filed:
Jan. 04, 2017
Hamamatsu Photonics K.k., Hamamatsu-shi, Shizuoka, JP;
HAMAMATSU PHOTONICS K.K., Hamamatsu-shi, Shizuoka, JP;
Abstract
A DFB laser element includes an active layerhaving a multiple quantum well structure including a plurality of well layersB having different thicknesses, a diffraction grating layerthat is optically coupled to the active layer, and a pair of cladding layers with the active layerand the diffraction grating layerinterposed therebetween. An effective refractive index of the diffraction grating layeris high, and a thickness of the well layerB increases as a distance from the diffraction grating layerincreases. In this structure, it is possible to reduce dependence on temperature when the DFB semiconductor laser element is miniaturized.