Read/Write 3-D Disk System

We propose to implement a terabyte optical disk using holographic storage in lithium niobate crystals. Lithium niobate crystals have been extensively characterized as a storage media and it is readily available commercially. The key innovation of the proposed system is the incorporation of the dynamic copying method with the 3-D holographic disk which compensates for the erasure of the stored holograms while they are read out. The specifications of the proposed 3-D disk are: terabyte capacity per disk, read/write capability, recording rate in excess of 50 Mb/second, readout rate of 250 Mb/sec, and access time estimated to be approximately 20 milliseconds. The proposed system yields very high storage density at approximately 113 bits per micron squared. The first phase of the proposed effort intends to demonstrate the feasibility of the proposed system. The phase I work plan includes the optimization of the copying schedule, the incorporation of error correcting capability into the system, the studying of alignment sensitivity issues, and the design of the 3-D disk prototype. (This work plan does not overlap that of another proposal submitted to Rome Laboratory. See Work Plan and Pending Research proposals for details.)