A light modulator includes elongated elements arranged parallel to each other. In a first diffraction mode, the light modulator operates to diffract an incident light into at least two diffraction orders. In a second diffraction mode, the light modulator operates to diffract the incident light into a...http://www.google.de/patents/US6829092?utm_source=gb-gplus-sharePatent US6829092 - Blazed grating light valve
