Patent ID: 9547127
Date: 2017-01-17
CPC Classifications: G02B

Claim:
1. A broadband communication system comprising: a polarization beam splitter, the polarization beam splitter comprising: a couple of second-stage directional couplers each being configured substantially same as the first-stage directional coupler except being complementary designed with a second coupling gap, a first second-stage directional coupler being cascaded to the first through port for further coupling the first primary TM mode portion to a second primary TM mode portion at a second through port with a second TM extinction ratio and a second second-stage directional coupler being cascaded to the first cross port for further cross-coupling the first primary TE mode portion to a second primary TE mode portion at a second cross port with a second TE extinction ratio; wherein the first and second coupling gap are set complementary for maximizing the first and second TE/TM extinction ratio respectively within a shorter and longer wavelength window of the predetermined wavelength band or vice versa; and a network.