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:
Aug. 24, 2004
Filed:
Jul. 08, 2002
The Furukawa Electric Co., Ltd., Tokyo, JP;
Abstract
A semiconductor laser includes a resonant cavity with a cavity length, an active layer structure provided within the resonant cavity and configured to radiate light in an optical gain distribution having a peak wavelength, an embedding layer provided within the resonant cavity and having a refractive index, and a diffraction grating embedded within the embedding layer and having a bandgap wavelength and a refractive index, the diffraction grating configured to select an emission wavelength of the resonant cavity independently of the peak wavelength in the optical gain distribution of the active layer structure. The embedding layer and diffraction grating are configured to provide operational characteristics satisfying the relationship 0<&lgr;e−&lgr;g≦100 nm, where &lgr;e is the emission wavelength of the resonant cavity &lgr;g is the bandgap wavelength of the diffraction grating. In addition, a difference in the refractive index of the diffraction grating and the embedding layer satisfies the relationship 0.29<n n , where n is the refractive index of the diffraction grating and n is the refractive index of the embedding layer.