A device for dynamic light spot size and shape control which is particularly suitable for vector addressing laser projectors to produce texture, more complex diagrams, and better animation. The curvature of a small reflective surface is changed by a transducer according to a signal. The reflective surface...http://www.google.com.au/patents/US5274492?utm_source=gb-gplus-sharePatent US5274492 - Light spot size and shape control for laser projector
