  Basing on the measurements of photoelastic coefficients, acoustic waves
velocities and the refractive indices, the possible geometries for acoustooptic
interaction in b-BaB2O4 crystals have been analysed. It has been shown that the
acoustooptic figure of merit achieves its maximum value when the transverse
acoustic wave v13 with the velocity 817m/s is propagated in YZ-plane. In this
case M2=95.35*10-15s3/kg.
