Patent ID: 8570644
Filing Date: 2013-10-29
Classification: G02B,G02F

Abstract:
1. An optical modulator comprising: first and second optical modulation units that are formed on a substrate; a polarization beam rotating unit that rotates at least one polarization beam of modulated light beams modulated by the first and second optical modulation units; and a polarization beam combining unit that is disposed outside the substrate and that includes a polarization beam combining element combining the polarization beams of the modulated light of which the polarization beams are rotated by the polarization beam rotating unit, wherein the polarization beam combining unit includes an optical system in which two opposed collimating systems are arranged, wherein the two opposed collimating systems include a first collimator to which the modulated light beams modulated by the first and second optical modulation units are input, and a second collimator to which an output light beam of the polarization beam combining element is input, wherein an input position of the second collimator is substantially located at the center of a position gap varying depending on the polarization beams of the output light of the polarization beam combining element, wherein at least one of the two opposed collimating systems include fiber collimators, respectively, and wherein at least one of the two opposed collimating systems is configured to include a ferrule.