A color-filter liquid crystal-on-silicon (LCoS) pico optical engine has been designed with polarization recovery. By combing nonimaging collection optics and a collimation lens, the collimated light's aperture is reshaped so that both of its two polarized parts can be polarization recovered and then collected by the relay lens. No polarization conversion system of traditional polarization recovery method is used, and the aperture of illumination optics does not increase. A design example of color-filter LCoS pico optical engine with 640×360 resolution is listed. High light efficiency of about 9.3 lumens per light-emitting diode watt and high irradiance uniformity of about 94% have been achieved. The thickness of the optical engine is 11 mm.