A Fast, Digital-Indexed Light Deflector

The device described in this paper is capable of positioning a light beam to any one out of, say, 1000 linearly arranged positions. The light beam is controlled by electric signals applied to electro-optic switches. The deflection is performed in either one or two dimensions. The positions are digitally indexed, thus allowing a high-speed-random access to each position. The locations of the positions are determined by the geometric design; therefore they are independent of the amplitude of the control signal and do not follow its fluctuations. The deflected light beam can originate from any source, and the light absorption in the deflector is reasonably small. Thus, when using a laser source, the outcoming beam can be very bright. The contrast ratio of the brightness in switched and unswitched positions is about 100 to 1. The maximum deflection rate depends on the allowable power dissipation in the electro-optic switches. A deflection rate of 2 × 106deflections per second seems feasible.