From Holography To Micro-Optics

Holography can store wavefields in light-sensitive material. Due to its flexibility and the potential of multiplexing several functions into one element, holography has also been proposed as a recording technique for micro-optical elements. This paper discusses the recording of holograms that perform the basic functionalities (deflection, focusing, and fan-out) needed in micro-optical systems. Emphasis is given to the optimum recording of fan-out elements and high-density multifacet holograms. Successful recording schemes are presented, which are easy to align and therefore are interesting for the fabrication of systems. The potential of holography is demonstrated by recording 10,000 lenslets on 1 cm₂ in a compact optical system. In addition, several highly efficient fan-out elements have been recorded as volume and surface-relief holograms.