Patent ID: 6236772
Filing Date: 2001-05-22
Classification: G02F

Abstract:
An optical modulator comprising:an input waveguide section, including a power divider providing two approximately equal outputs from a single input;a pair of coupled waveguides connected to receive energy from the power divider, and positioned in coupling proximity to each other in a coupling region;a first means for applying a first electric field to the coupled waveguides in a first section of the coupling region to thereby produce in the first section a first difference .DELTA..beta..sub.1 between the propagation constant of the first waveguide and the propagation constant of the second waveguide; anda second means for applying a second electric field to the coupled waveguides in a second section of the coupling region to thereby produce in the second section a second difference .DELTA..beta..sub.2 between the propagation constant of the first waveguide and the propagation constant of the second waveguide;wherein .DELTA..beta..sub.1 and .DELTA..beta..sub.2 have opposite signs, whereby the intensity of optical output from at least one of the coupled waveguides varies approximately linearly with the strength of the first and second electric fields such that said optical switch achieves better than 70% linearity,wherein the second electric field is of the same polarity as the first electric field, wherein said optical switch is fabricated in a polymer material, and wherein the second section of the coupling region has an electro-optic coefficient of opposite sign with respect to an electro-optic coefficient of the first section of the coupling region due to reverse poling of the polymer in either the first section or the second section of the coupling region.