Optical Design of External Illuminance for Display Backlight Module

This work proposes a newly developed optical design of a backlight module which, for the purpose of guiding sunlight from various directions into the backlight module, consists of a reflective concentrator panel, a micro lens array, a thin film acting as a light guide film (LGF). Normally, common mirrors only reflect a specific angle of light. Since the position of the sun varies over time, we designed a reflector-based optical module which included a reflector and a micro-lens array with a thin film in order to concentrate the intensity of sunlight as it is distributed at different times. Regarding the stack characteristic, the module of the static concentrator increased the area of concentration. After simulation, it is concluded that using this special optical design will improve the efficiency of the static concentrator module by 40.64% when sunlight comes from the direction of 11 o´clock, and the efficiency by 39.18% from 12:00 noon. This efficiency increases by 52.38% when sunlight comes from the 2 o´clock direction.