A LCD backlighting device that uses a diffractive light extractor has been
developed for applications in which pointlike light sources are employed. T
he novel system eliminates the images of Light sources, which appear as bri
ght lines emanating from each source in the conventional diffractive approa
ch. In addition, the system illuminates the LCD uniformly: Modulation of th
e diffractive structure as a function of position is used to control the ou
tput field of this extended planar light source. (C) 2001 Optical Society o
f America.