Ultrasonic instruments used in surgical applications (e.g., ophthalmology, neurosurgery, dentistry) have vibrating tips driven at frequencies from 20 to 60 kHz, and maximum peak-to-peak tip excursions ranging up to several hundred micrometers. To study the tip motion, a stroboscopic system has been developed consisting of a digitally generated delay that automatically steps through the excursion cycle, a commercial xenon flashlamp strobe, and optics that permit video display and recording. The digital delay uses two 8-bit, synchronous binary counters with asychronously loaded data inputs. These counters are configured so as to produce a pulse train for strobe triggering that has successive pulse periods that differ by one clock cycle. Of the two possible sources for image blur, the finite light pulse duration and strobe jitter, the former is more significant because light pulse durations of less than 1 (mu)s are difficult to obtain with xenon flashlamps. Image magnifications of up 550x are possible with the technique, with a tip displacement resolution of approximately 5 (mu)m. The technique has been used to visualize the tip motion of an ophthalmic phacoemulsifier operating at 28 kHz and having a maximum tip excursion of 100 (mu)m.