Abstract

We report on measurements of photoinduced diffraction in prism coupled slab polymer waveguides.¹ Optical damage in the form of diffractive mode conversion was observed when light whose wavelength was slightly longer than the absorption edge of disperse red 1 was coupled into photochromic gratings in slab waveguides of disperse red 1 in polymethylmethacrylate. Slowly growing satellite beams in the outcoupled light were attributed to anisotropic scattering between the lowest order TE mode and the lowest order TM mode caused by self-diffraction from a grating produced through the photochromic effect. We have also investigated the effect of mode coupling changes on the determination of diffraction efficiency and sensitivity in waveguide experiments. Diffraction efficiencies predicted by measurements of the modulation depth in the guide are found to overstate the actual diffraction efficiencies which could be observed in this geometry.

© 1993 Optical Society of America