As more and more kinds of portable display devices are available in the market, there are also non-self-emissive display panel now. To meet the need of reflective display panels and strengthen their weakness, we proceed the research of compact portable front light unit to provide extra light and enable them can be read in dark circumstances. In this thesis, we guided light using reflective tapered light pipes firstly. Except for software simulation of illumination, we also manufacture a real tapered light pipe and compare the result with simulation. To raise transfer efficiency of light and eliminate the effect brought by the bright spot, we also lead the research of refractive component. By the usage of freeform surface lens or microlens array, we proceed to redistribute light to adjust uniformity and efficiency. At last, we compared the illumination effect of freeform lens with microlens array transformed from freeform lens.