<title>Holographic data storage in phenanthrenequinone-doped PMMA</title>

Abstract

Phenanthrenequinone (PQ)-doped poly(methyl methacrylate) (PMMA) is a photopolymer holographic recording material that can be made in large thicknesses and does not exhibit any shrinkage. Hologram are made permanent by a post-recording diffusion amplification process. PQ-doped PMMA thus exhibits may properties which make it an ideal candidate as a high- density read-only holographic data storage medium. Recently we reported the holographic recording characteristics of phenanthrenequinone (PQ) doped PMMA. We now demonstrate the holographic storage of binary data in this material. Shift multiplexing is used to store multiple holographic data pages in millimeter thick material samples. Each data page consists of a random array of binary 40 micron pixels. Recording is performed near the Fourier transform plane of the data mask, allowing high bit-densities to be achieve.d The signal to noise ratio of stored data pages is used as an indication of hologram quality and data integrity. Bit density limitations are discussed with respect to the current performance of the recording material.