An optical apparatus comprises a light source, an optical member and a
spatial light modulator. The optical member comprises optically
transmissive material and has a textured major surface receiving light
from the light source. The textured surface comprises first and second
pluralities of non-intersecting elongate features. The pluralities are
angled with respect to each other by less than about 90.degree. and
intersect each other so as to form total internal reflection structures.
The spatial light modulator has rows or columns of pixels for receiving
light from the optical member at a major surface. The light source may be
(i) a light guide, or (ii) a source of light providing, to the optical
member, light having a peak luminance that is shifted from a normal
direction to the textured major surface by more than about 30.degree..