| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a phase shifter on a semiconductor substrate, that can adjust birefringence with high accuracy. <P>SOLUTION: A PBS 100 includes a first optical coupler 110, a birefringence application part 120, a birefringence adjustment part 130, and a second optical coupler 140 on a semiconductor substrate 101 having a sphalerite type structure. The birefringence application part 120 and the birefringence adjustment part 130 function as a phase shifter. A first electrode 102D is disposed on a fifth waveguide part 102C of a first arm waveguide 102, and a second electrode 103D is disposed on a second inclination part of a fourth waveguide part 103B of a second arm waveguide 103. A first direction in which the first electrode 102D is disposed and a second direction in which the second electrode 103D is disposed are directions where, when unit voltage is applied to the both electrodes, phase difference between the upper and lower arm waveguides to TM polarization is suppressed and phase difference between the upper and lower arm waveguides to TE polarization is increased in the birefringence adjustment part 130. <P>COPYRIGHT: (C)2013,JPO&INPIT |
