Title :
Guided-wave acoustooptic tunable filters using simple coupling weighting technique
Author :
Yamamoto, Y. ; Tsai, C.S. ; Esteghamat, K.
Author_Institution :
California Univ., Irvine, CA, USA
Abstract :
A simple acoustooptic (AO) coupling weighting technique for sidelobe suppression that involves only variation of the width of the surface acoustic wave (SAW) slot waveguide is presented. Calculations on single-stage and multistage acoustooptic tunable filters (AOTFs) consisting of an optical channel waveguide and a SAW slot waveguide in LiNbO3 have shown that waveguide width coupling using the Hanning weighting function provides significant improvement in sidelobe suppression. Specifically, using the Hanning function a sidelobe level of -26 dB is predicted as compared to that of -9 dB with the conventional uniform coupling. Calculated results together with the design, fabrication, and preliminary measured performance characteristics of a single-stage guide-wave AOTF in YX-LiNbO3 substrates at the optical wavelengths of 0.6328 and 1.55 μm are reported
Keywords :
acoustic waveguides; acousto-optical devices; integrated optics; lithium compounds; optical filters; optical waveguides; surface acoustic wave filters; 0.6328 micron; 1.55 micron; Hanning weighting function; LiNbO3 waveguide; SAW slot waveguide; coupling weighting technique; design; fabrication; guided wave filters; multistage acoustooptic tunable filters; optical channel waveguide; performance characteristics; sidelobe suppression; single-stage; Acoustic waveguides; Acoustic waves; Optical coupling; Optical design; Optical device fabrication; Optical filters; Optical surface waves; Optical waveguides; Surface acoustic waves; Wavelength measurement;
Conference_Titel :
Ultrasonics Symposium, 1990. Proceedings., IEEE 1990
Conference_Location :
Honolulu, HI
DOI :
10.1109/ULTSYM.1990.171434
