High Speed Time-Frequency Domain Holographic Storage

Image storage in coherent time-domain optical memory (CTDOM) has been demonstrated successfully by using high-power pulsed lasers.1-2 Like photochemical hole burning3 and photorefractives,4 this time-domain approach to image storage has the potential of offering ultrahigh storage density and fast data access time. Unlike other optical memories, CTDOM is capable of providing ultrahigh image transfer rates and offers features such as in-memory image processing.5 However, difficulties arise in using the conventional time-domain approach to image storage, namely multiple images per frequency channel. For example, existing image composers such as an electronically-addressed spatial light modulators (SLM) do not have switching times fast enough to accommodate the required recording speeds (≳ MHz). High-power pulsed lasers are needed to make retrieved images detectable by electronic cameras. In addition, features such as random frame (or page) access and variable playback speed are not available with the conventional approach.