Film, oscilloscopes, stroboscopes, computerized, kinetic and live images. Thus stroboscopes are also used to measure frequency. They are stroboscopes that flicker a light at the same frequency as the note. Stroboscopes are sometimes used to induce this effect intentionally. Stroboscopes have been used to create static images of an action. Stroboscopes produce flashes of light that are timed to the patient's vocal frequency. Edgerton used stroboscopes to study synchronous motors for his Sc.