| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a semiconductor tunable laser that has a wider tunable bandwidth than ever before and that simplifies accurate oscillation wavelength control. <P>SOLUTION: A filter area 420 of a semiconductor tunable laser 400 includes a first MZI 421 and a second MZI 422 that are arranged in parallel and are connected to two output ports of a 2×2 optical coupler 423, respectively. Each MZI is a symmetric MZI that has two isomorphic arm waveguides between two 2×2 optical couplers. Each of the arm waveguides comprises a Fabry-Perot etalon that includes: a first mirror that is connected to the output port of one 2×2 optical coupler; and a second mirror that is connected to the first mirror through an optical waveguide with predetermined length (first length L1 for the first MZI 421 and second length L2 for the second MZI 422) and is connected to an input port of the other 2×2 optical coupler. The output ports of the other 2×2 optical coupler are provided with high reflective mirrors 424 and 425 with a reflectivity of 90% or more, respectively. <P>COPYRIGHT: (C)2013,JPO&INPIT</p> |
