Frequency multiplying optical waveguide mfr. - by selective polarisation, exposure and development of photosensitive layer

摘要

Prodn. of an optical waveguide, with domains (11,12) electrically polarised in various directions for optical frequency multiplication, involves (i) applying a waveguide layer (2) of electrically polarisable, photosensitive material, which cross-links on exposure and subsequent developments, onto a substrate surface; (ii) subjecting the layer (2) to an electric field (E) aligned in one direction (r1 or r2); (iii) selectively exposing and developing the layer using an exposure mask to fix the polarisation direction in the exposed sections while leavingg the unexposed sections unchanged; (iv) subjecting the layer (2) to an electric field (E) aligned in another direction (r2 or r1); and (v) exposing and developing the previously unexposed layer sections to fix a different polarisation direction in these sections. USE/ADVANTAGE - The waveguide is useful for quasi-phase matching second harmonic generation (QPM-SHG) in semiconductor laser applications. It has improved structure quailty.(esp. quality (esp. the requisite mfd. fineness and precision), the structure widths for short wave (blue) light prodn. being maintainable over the entire SHG structure at 1-4 microns with 0.5 micron precision.