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. 17, 2012
Filed:
Aug. 20, 2008
Atsushi Sugiyama, Hamamatsu, JP;
Takahide Ochiai, Hamamatsu, JP;
Kazuue Fujita, Hamamatsu, JP;
Naota Akikusa, Hamamatsu, JP;
Tadataka Edamura, Hamamatsu, JP;
Shinichi Furuta, Hamamatsu, JP;
Atsushi Sugiyama, Hamamatsu, JP;
Takahide Ochiai, Hamamatsu, JP;
Kazuue Fujita, Hamamatsu, JP;
Naota Akikusa, Hamamatsu, JP;
Tadataka Edamura, Hamamatsu, JP;
Shinichi Furuta, Hamamatsu, JP;
Hamamatsu Photonics K.K., Hamamatsu-shi, Shizuoka, JP;
Abstract
A DFB quantum cascade laser element that can reliably CW-oscillate a single-mode light even at room temperature or a temperature in proximity thereof is provided. In a quantum cascade laser element, a top-grating approach for which a diffraction gratingis formed on a laminateis adopted, and thus in comparison with a buried-grating approach, deterioration in temperature characteristics of the laser element and decline in the yield and reproducibility are suppressed. In addition, since the thickness of a cladding layerlocated between an active layerand the diffraction gratingis within a range of 42±10% of the oscillation wavelength, weakening of light seeping from the active layerto the diffraction gratingor an increase in light leakage is prevented. Consequently, by the quantum cascade laser element, a single-mode light can be reliably CW-oscillated even at room temperature or a temperature in proximity thereof.