57.4: Thin Side-Lit, Hollow-Cavity Flat LED Lighting Panel for Ultra-Uniform LCD Backlight Applications

A new and thin, FL(2)p(Flat LED Lighting Panel) with ultrahigh-uniformity for LCD backlight is presented. It has a hollow-cavity structure consisting of a pair of LED/collimator units, a slightly curved bottom reflector and a top diffuser, without any planar light guide inside. It has a great advantage of making itself thinner, less weight and lower cost. The LED/collimator unit has a collimating cylindrical lens and a side-placed RGB LED array. The collimating lens is developed particularly for higher-coupling efficiency and narrower beam to achieve thinner structure and more excellent uniformity.