The photoelastic properties of α‐HIO3 have been measured and the applicability of the material for acousto‐optic device applications determined. In the blue and green portions of the visible the material has the highest figure of merit, n6p2∕ρv3, of any known crystal, approximately twelve times that of LiNbO3 and fifty times that of fused silica. Other desirable properties for these applications include (a) the availability of large solution‐grown single crystals of high optical quality, (b) low acoustic and optic losses, and (c) the absence of ``optical damage.''
A simple acoustically driver beam deflector was also constructed to demonstrate the potential of this material. It was found that 70% of a 0.63‐μ laser beam could be deflected, over a bandwidth of 55 MHz, with an electrical drive power of 265 mW, while 70% of a 0.488‐μ laser beam could be deflected over the same bandwidth with 94 mW of electrical power.