| 摘要 |
A method for making an apodized Bragg grating in a photosensitive, planar, linear waveguide. A photosensitive, planar, linear waveguide (4) is provided on a surface of a substrate (2). A patterned phase mask (6) is placed between the waveguide and a laser beam (8). The waveguide is exposed 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. The beam has a smoothly varying intensity profile, and the exposure is conducted at an angle of more than 0 and less than 90 (degrees) to the longitudinal axis of the waveguide under conditions sufficient to induce a modulation in the index of refraction of the waveguide and impart an apodized Bragg grating in the waveguide corresponding to the phase mask pattern.
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