HOLOGRAPHIC STORAGE SYSTEM FOR READING A HOLOGRAM STORED ON A HOLOGRAPHIC STORAGE MEDIUM AND A METHOD CARRIED OUT THEREWITH

摘要

The invention relates to a holographic storage system (1) for reading a h ologram (7) stored on a holographic storage medium (6). The system (1) compr ises: storage medium holding means arranged along an optical path of a refer ence beam (3); a spatial light modulator (SLM) (4) arranged along said optic al path for encoding a reference beam (3) with a code pattern (15); a detect or (5) for detecting an image of the reconstructed hologram (7); and a servo control unit (14) for determining a misalignment of said reference beam (3) and said storage medium (6) from the detected image and for acting upon sai d SLM (4) to shift said code pattern (15). The invention further relates to a method of reading a hologram (7) stored on a holographic storage medium (6 ) comprising the steps of: a) encoding a reference beam (3) with a code patt ern (15) created by a spatial light modulator (SLM (4)); b) detecting an ima ge of the reconstructed hologram; c) determining a misalignment of said refe rence beam (3) and said storage medium (6) from the detected image; and d) s hifting said code pattern (15) on the SLM (4) based at least in part on said misalignment.