LIQUID-CRYSTAL DISPLAY LIGHTING SYSTEM (ALTERNATIVES) Russian patent published in 2007 - IPC H04N5/262 G09G3/18 G02F1/1335 

FIELD: liquid-crystal displays.

SUBSTANCE: proposed liquid-crystal display lighting system has sequentially disposed light source, optical system, optical film, polarization film, and microprism film; optical film is made of transparent material and has at least one optical element incorporating first refracting surface and opposing interconnected second refracting surface and reflecting surface, as well as side surfaces; light source is designed to generate diverging light beams; microprism film is designed to pass some portion of light beams through desired aperture and to reflect some portion of light beams in direction of reflecting surface whose external aperture is practically equal to that of first refracting surface; internal aperture equals that of second refracting surface; reflecting surface is designed to partially depolarize some portion of light reflected by polarization plate and for reflecting this portion of light and some portion of light beams reflected by microprism plate to polarization plate.

EFFECT: reduced angular aperture, enhanced light efficiency.

14 cl, 6 dwg