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:
Feb. 02, 2010
Filed:
May. 25, 2005
Kenji Mizutani, Tokyo, JP;
Koji Kudo, Tokyo, JP;
Kenji Sato, Tokyo, JP;
Jan DE Merlier, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
To facilitate phase adjustment in an external resonator type wavelength-variable laser. An external resonator type wavelength-variable laser () includes a semiconductor light amplifier (), a wavelength selection filter () having periodic frequency characteristics, an external resonator (), and a wavelength-variable filter (). Δf is divided into one or more regions. The following conditions are satisfied for one Δfregion: m=(j×Δf)/Δfwhere Δf: a period of the wavelength selection filter, ΔfFP: a Fabry-Perot mode interval dependent on a length of the external resonator, j: an integer not smaller than 1 and not larger than (Δf/Δf). A coefficient Mis an integer obtained by rounding off the first digit after decimal point of the coefficient m. A coefficient Nis an integer obtained by discarding the first digit after decimal point of Δf/(j×Δf). In this regard, a relation of (|N×2π(M−m)|<π/2) is satisfied for one j.