A projection display comprising: a transmissive spatial light modulator (10); an illuminator (1, 20, 21, 30) for illuminating the modulator from the front thereof; and a hologram (32) disposed at the rear of the modulator for imaging and reflecting back through the modulator light from the illuminator...http://www.google.com.tw/patents/US6595648?utm_source=gb-gplus-share專利 US6595648 - Projection display
