Inherent apodization of lenses encoded on liquid-crystal spatial light modulators

Focusing diffractive optical elements encoded in liquid-crystal spatial light modulators yields an inherent equivalent apodization of the focused spot as a result of the pixelated nature of these devices and the finite extent of each pixel. We present a theoretical explanation for and experimental evidence of this effect. We demonstrate an experimental procedure for measuring the apodization and a method to compensate for this effect. [C] 2000 Optical Society of America OCIS codes: 230.3720, 120.4820, 110.4100, 110.2990, 260.1960.