Abstract: | Abstract— The commercial backlight unit for a portable liquid‐crystal display (LCD) device typically consists of several light‐emitting diodes (LEDs) as the light source, a couple of prismatic sheets and diffusers, and a guide plate for backlight optics. A simplified backlight unit for portable LCDs, merely consisting of a hologram‐imprinted light‐guide plate (H‐LGP) and one diffuser, is proposed in this paper. By employing H‐LGP, it is expected that several optical films essential to the conventional backlight unit can be eliminated. This paper aims to improve the optical efficiency of LGPs by deriving the design parameters of the H‐LGP and performing the related computations. The angular luminance distribution of the emanating light from H‐LGP has been measured and compared with the results obtained by simulation. A proper collimation is necessary in order to increase the luminance. The backlight developed through this work has high optical performance combined with low cost. |