Multiple chips are often bonded in a small single package of LED to obtain higher light flux output. However, the nonuniformity of light pattern always exists due to the high order collimating lamp, which uses the MCLED (Multi-chips LED) as the source. In this paper, the light pattern uniformity of lamp composed of four-in-one MCLED, whose thickness of phosphor layer and the length of lamp are respectively 0.1 mm and 10 mm, is simulated and analyzed. The ray tracing simulated by computer with varying the spacing of chips, concentration of phosphor, shape of lamp, and the corresponding uniformity of light pattern will be analyzed and discussed in detail.
In this study, a collimated LED light source has been developed as a colorful liquid crystal display backlight, which is driven by a two-field driving scheme to display color. In each field, the angular rays of two colors from LEDs are collimated by a collimation lens, redirected by a light guide and converged by a cylindrical-lens array to map into corresponding sub-pixel positions for efficiently displaying color image. The simulation results of the backlight module and the corresponding experimental results will be discussed in detail.