This far-fetched scenario comes one step closer with the announcement of what could be the first material suitable for making holographic optical storage disks 1 .
Holographic storage is like three-dimensional photography.
Information is encoded by passing a laser beam through a mask of holes to irradiate a block of light-sensitive material. Within the block, the laser crosses a second 'reference beam', setting up an interference pattern of light and dark spots. These spots leave an imprint on the block, just as light leaves an imprint of tiny black and white patches on photographic film. But unlike photographic film, holographic storage material can be used to record many superimposed 'images' of light and dark spots, each one imprinted with a reference beam shone from a different angle. Each image can be 'read out' separately using two crossed laser beams to reconstruct the light pattern used in the writing step.