Y. Bitou et T. Minemoto, Dependence of the contrast ratio on crystal thickness in an electroabsorptive spatial light modulator that uses GaAs, APPL OPTICS, 37(35), 1998, pp. 8227-8232
The contrast ratio of an optically addressed spatial light modulator that u
ses electroabsorption in a GaAs single crystal is discussed experimentally
and theoretically. The modulator has the same structure as a Pockels readou
t optical modulator. The contrast ratio depends strongly on the change in t
he absorption coefficient and on the thickness of the GaAs crystal. From th
e experimental results and from theoretical investigations of the Franz-Kel
dysh effect, the change in the absorption coefficient is estimated by use o
f the quadratic equation of an applied electric field that is not excessive
ly strong. Under this condition, an optimum thickness of the GaAs crystal p
late that will yield the maximum contrast ratio can be determined. (C) 1998
Optical Society of America.