Microholograms recorded in a thermoplastic medium for three-dimensional data storage

This paper presents a three-dimensional optical data storage system that combines a new recording material with a microholographic data format. The micro-holographic approach stores data as single-bit micro-holograms arranged in multiple layers throughout the volume of the disk, similar in format to standard physical layer formats. This approach offers much less sensitivity to environmental conditions than the page-based holographic approach in addition to an increased compatibility with current technologies. The new recording medium is based on an injection-moldable, dye-doped thermoplastic material that makes mass distribution of the new format economically viable. The recording of the micro-holograms in the new material indicates that the dimensions of the micro-holograms are larger than those calculated using simple laser beam waist approximations and that multiple layers of micro-holograms significantly impact signal levels. Ultimately, the results show that calculations of data densities achievable by the micro-holographic approach must take these effects into account.