The possibility of employing a time‐varying refractive‐index gradient, generated by an ultrasonic standing wave in solids and liquids, to provide nonmechanical optical‐beam scanning has been investigated in detail. Heretofore‐unobtained deflections of sufficiently large angles to be of practical value in active optical systems have been achieved. These angles range between 3° and 6° at frequencies below and above 200 kc/sec. respectively. Standard slit and photomultiplier techniques were employed to study the effects of stress‐induced birefringence in crystal quartz on the attainable angular movement of two collinearly deflected light beams that were orthogonally plane polarized. High‐speed streak photography was used to measure the fidelity of the light beam as it emerged from a tetrachloroethylene ultrasonic cell. The photographic technique was utilized to evaluate effects of (1) light‐beam diameter/sonic‐wavelength ratio, (2) light‐beam transit position relative to the sonic‐pressure nodal point, and (3) light‐beam angular‐deflection amplitude.