Patent ID: 6842544
Filing Date: 2005-01-11
Classification: G02B

Abstract:
1. A process for forming an apodized Bragg grating in a photosensitive, planar, linear waveguide which consists essentially of: providing a photosensitive, planar, linear waveguide on a surface of a substrate, which waveguide defines a longitudinal axis; positioning a patterned phase mask between the waveguide and a laser beam having a guassian intensity profile; exposing the waveguide through the phase mask to the laser beam wherein either the laser beam is moving at a substantially constant velocity with respect to the substrate and phase mask, or the substrate and phase mask are moving at a substantially constant velocity with respect to the laser beam, which beam has a smoothly varying intensity profile, and which exposure is conducted at an angle of more than 0° and less than 90° to the longitudinal axis under conditions sufficient to induce a change in the index of refraction to the waveguide and impart an apodized Bragg grating in the waveguide corresponding to the phase mask pattern.