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This paper presents a three-dimensional optical data storage system that combines a new recording material with a micro-holographic 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.

In the context of designing a three-dimensional optical-memory device, we investigate the cross section of two-photon absorption of a photochromic material as a function of the relative orientation of polarization vectors of light waves involved in two-photon data writing. It is demonstrated that, with an appropriate choice of polarization vectors of writing laser waves, one can considerably increase the efficiency of two-photon data writing.