Patent ID: 7444039
Filing Date: 2008-10-28
Classification: G02B,G02F

Abstract:
1. An optical modulator comprising: a thin plate made of a material having an electrooptic effect and having a thickness of 20μm or less; an optical waveguide formed in a top surface or a bottom surface of the thin plate; and a modulation electrode which is formed in the top surface of the thin plate to modulate light which propagates in the optical waveguide, wherein the optical waveguide has an optical junction portion in which a plurality of optical waveguide portions are joined together, a shielding means for shielding a portion of radiation light radiated from the optical junction portion, and the shielding means is a concave portion or a through-hole formed in the thin plate, a shortest distance from the waveguide to the shielding means is 5 to 10 μm, and a length of the shielding means in a direction perpendicular to the waveguide is at least 0.5times a diameter of a fiber coupled to the optical waveguide.