PHOTOWRITTEN GRATINGS IN ION-EXCHANGED GLASS WAVE-GUIDES

The fabrication of an ion-exchanged waveguide beam deflector containing a photowritten grating is described. The planar waveguide was fabricated by thermal K+ exchange in a borosilicate glass. The grating was written by photobleaching an absorption defect centered at 330 nm, which was created by gamma-ray irradiation of the glass. The bleaching was accomplished with the 351-nm line from an argon laser. The device achieved 35% deflection efficiency at 633 nm, which corresponded to a grating with a photoinduced index change of 2.6 x 10(-5). This is to our knowledge the first demonstration of an ion-exchanged glass waveguide device containing a permanent photowritten grating.