Patent ID: 8818203
Filing Date: 2014-08-26
Classification: G02B,G02F

Abstract:
1. An optical modulator comprising: a light input unit configured to receive an incident optical signal which has not been modulated, to split the incident optical signal into a first optical signal and a second optical signal, and to transmit the first and second optical signals to a first path of an optical waveguide and a second path of the optical waveguide, respectively; a first phase shifter positioned in path and configured to shift a phase of the first optical signal by a first angle in response to a first electrical signal; a second phase sifter positioned in the second path and configured to shift a phase of the second optical signal by a second angle in response to a second electrical signal; and a light output unit configured to combine a signal received through the first path and a signal received through the second path and to generate an output optical signal therefrom, wherein at least one unit among the light input unit and the light output unit comprises a vertical grating coupler, wherein the light input unit comprises: a slanted grating coupler configured to receive the incident optical signal and to transmit the received optical signal in one direction; and a Y-splitter configured to split the incident optical signal received from the slanted grating coupler into both the direction of the first path and the direction of the second path of the optical waveguide with equivalent proportions, and wherein the light output unit comprises a vertical grating coupler configured to combine the second optical signal with a phase-modulated signal output from the first phase shifter and to output the output optical signal in a direction vertical to a direction in which the second optical signal and the phase-modulated signal are input to the light output unit.