Massively-parallel writing and reading of information within the three-dimensional volume of an optical disk, particularly by use of a doubly-telecentric afocal imaging system

Abstract

A volume radiation memory, nominally a 2.5 cm (1″) diameter 6 mm thick optical disk, is preferably written in parallel by two-photon absorption within, and read with massive parallelism by a single-beam-induced fluorescence of, spherical voxels of nominal diameter 2 microns spaced 2 microns center-to-center and arrayed 32×128 in planar segments that are tilted typically 40° to the planar surfaces of the disk, and that are typically located within a 5 mm thick central volume of the disk. Imaging of the voxels within the tilted planar segment for reading is through a two-lens doubly-telecentric afocal lens imaging system to a detector, normally an array of active pixel sensors or charge-coupled devices, located in the conjugate plane. Voxel illumination for reading may be orthogonal from the side of the disk, confocal-theta from a side of the disk, or co-linear through the doubly-telecentric afocal lens. Volumetric storage capacity is typically 5.89 gigabits (5.9×10E9 bits), and readout speed is typically 1.6 gigabits/second (1.6×10E9 bits/second) with a 30 millisecond maximum latency at a 1300 rpm disk rotation rate.