The technology of Integrated acoustooptic modulation

摘要

In this paper, a integrated chip of acoustooptic modulation is described. Two optimized waveguide geodesic lens having the functions of collimation and focus and two serial acoustooptic Bragg modulator producing frequency shift are integrated on one Ti diffused LiNbO3 waveguide substrate. In our experiments, we use high temperature diffused technics with depositing 50nm thick Ti film to produce Ti diffused LiNbO3 optic waveguide with low loss. Experimental interdigital transducers have the characters of 107MHz center frequency, interdigital width is 8 μ m, acoustic period is 32 μ m, interdigital number is 10, acoustic aperture is 8mm. The geodesic lens' focus is 8mm, aperture is 8mm, transition region is 10mm. There is null curvature singularity while geodesic lens rotating generatrix is optimized. The substrate is made of Ti diffused LiNbO3, its length is 46mm, height is 2.5mm and width is 30mm.