Holographic laser scanning system employing a holographic scanning disc with holographic facets having dual-fringe contrast regions optimized for scanning and light collection operations. In the preferred embodiments, the first region of each holographic facet is optimized for laser light having a first...http://www.google.de/patents/US6003772?utm_source=gb-gplus-sharePatent US6003772 - Holographic laser scanning system employing holographic scanning disc having dual-fringe contrast regions for optimized laser beam scanning and light collection operations
