LED BACKLIGHT MODULE HAVING REDUCED LIGHT LEAKAGE, INCREASED LIGHT EXTRACTION EFFICIENCY AND REDUCED COST

摘要

A backlight module includes a light guiding board and a plurality of LED light sources located at a flat lateral side of the light guiding board. The light guiding board comprises a first portion and a second portion, and the first portion is located between the LED light sources and the second portion. The first portion is intimately matched and engaged with the second portion. The refractive index of the first portion is unequal to that of the second portion. A plurality of micro-structures are formed on the surface of the first portion facing towards the second portion. The micro-structure is used for diffusing the light of the LED light sources when the light travels from the first portion to the second portion. The second portion is quite larger than the first portion.