APPARATUS FOR LCD BACKLIGHTING

摘要

Systems and methods for providing an LCD with a collimated backlight and a non-Lambertian diffuser are described. An LCD system includes: an illumination source (60) for producing light; a collimating waveguide (80) optically connected to the illumination source, the collimating waveguide including a top surface (146), an incident end (130) and a plurality of substantially parallel optical elements (140) for redirecting light from the incident end to,and through, the top surface, each of the plurality of substantially parallel optical elements including a first facet (142) that is nonparallel to the top surface and a second facet (144) that is nonparallel to the top surface; a reflector (70) optically connected to the light source and optically connected to the collimating waveguide, the reflector (1) at least partially surrounding the illumination source, and (2) reflecting light from said illumination source to said incident end by direct reflection; a liquid crystal display (40) optically connected to the collimating waveguide; and a non-Lambertian diffuser (30) optically connected to the liquid crystal display for directing light from said liquid crystal display. The light from the reflector is directly incident upon the incident end. The systems and methods provide advantages in that the light from the LCD is bright and homogeneous.