Acoustic Birefringence in Liquids

Observations of acoustically induced birefringence in liquids have been reported by several authors since the initial observation by Lucas in 1938. In most of these observations, a polarization analysis was performed on a collimated light beam immediately upon traversing an acoustic beam and the time‐average induced birefringence calculated. Since acoustic frequencies in the low‐megacycle range and acoustic pressures of the order of 0.5 atm are common, ultrasonic light‐diffraction effects are significant under these experimental conditions and must be carefully considered in analyzing the experimental data. In this paper, the light distribution that results from passing a plane, linearly polarized light beam through a liquid, made optically uniaxial by an acoustic beam, is discussed for both the near‐ and the farfield. Experimental measurements on several liquids that exhibit large birefringence effects are reported for both the near‐ and farfield and the interpretation of these data discussed in terms of...