摘要 |
A single-imager micro projection engine includes a reflective polarization modulation imager, a projection lens system and a polarization conversion assembly integrating a light source with a planar polarization beam splitter and a reflective quarter wave composite plate in parallel. The polarization conversion assembly lets through first polarization portion of illumination light in first polarization state from the light source for illuminating a first half facing area on the reflective polarization modulation imager, while reflecting second portion in second polarization state perpendicular to first polarization state towards the reflective quarter wave composite plate. The reflective quarter wave composite plate reflects, while 90-degree polarization rotating from second polarization state to first, the received second portion back to the planar polarization beam splitter. The reflected and polarization-rotated second portion also in first polarization state transmits through the planar polarization beam splitter and illuminates a second half facing area on the reflective polarization modulation imager. Modulated and 90-degree polarization-rotated images produced by both the first and second half facing areas of the reflective polarization imager are reflected by the planar polarization beam splitter towards the projection lens towards an external projection screen.
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