Patent ID: 7692861
Filing Date: 2010-04-06
Classification: G02B,Y10S

Abstract:
1. An illumination system for receiving first and second input light sources, the first and second input light sources comprising first and second colors, respectively, the illumination system comprising: a polarizing beam splitter operable to receive the first input light source at a first input and the second input light source at a second input, and to split the two input light sources into first and second mixed lights, and to output the first mixed light at a first output and the second mixed light at a second output; and first and second optical filters adjacent to the first and second outputs, respectively, the first and second optical filters operable to selectively convert polarization states of the two mixed lights; wherein the first and second optical filters are retarder stack filters; and wherein the first and second optical filters are operable to convert the polarization state of light having a respective first wavelength while leaving unchanged the polarization state of light having a respective second wavelength, wherein the polarization state of light having the first respective wavelength is converted from a first polarization state to a second polarization state.