||In the era of the information-boom, the demand for display systems to provide higher information content is increasing. Among the existing display technologies, projection display offers the marvelous capability for displaying higher resolution, larger images, as well as vivid color and lightweight, thus being one of the most promising candidates for the high-information-content displays. Especially for liquid crystal on silicon (LCOS) projectors, the separation of the imaging devices and the light source also makes the luminous output >104 lumens realizable. Moreover, along with the advance of the silicon-based light valve, the resolution can be quite high. Therefore, LCOS projection displays with these attractive features and the potential of low cost are expected for wide applications. The objective of this thesis work is to design and/or characterize the key optical components related to LCOS projectors in order to obtain the optimal LCOS projection systems on size, performance, and price. The focus of this work is mainly on the optics of projection systems, including the illumination optics, the polarization optics and the imaging optics. The first part of the thesis concentrates on the illumination system for LCOS projectors. One novel LED illumination system has been developed. The major problems on the existing LED light sources, such as light collimation and heat dissipation have been solved. One LED illumination system containing 40 1W-LEDs at the area of 160 mm2 is demonstrated. The second part of the thesis is dedicated to various polarization optical components, including polarization interference filters, polarizing beam splitters (PBSs) and LCOS light valves. For polarization interference filters, one new design method is proposed. Several filters have been made based on this new method. For PBSs, three different PBSs are designed and/or analyzed according to the system requirements. In LCOS light valves, the LCOS optical modes, color filter LCOS and LCOS-panel measurements are discussed in detail, respectively. The third part of the thesis is devoted to one telecentric projection lens design (the imaging system). Finally, the integrations of the whole system based on the optical components we studied in this thesis are discussed in detail. The prototypes of LED based and arc lamp based LCOS one-panel projectors have been made.