NTT Develops Stamp-Size Hologram Memory

Found on NE Asia Online on Monday, 16 February 2004
Browse Technology

Nippon Telegraph and Telephone Corp (NTT) announced on Feb 12 that it has developed a prototype of a new high-capacity memory storage device, designed with a multi-layered waveguide structure and based on thin-film holography.

The company has produced a 100-layer postage stamp-sized media prototype with a 1GB memory capacity constructed from plastic material, and a small prototype drive for reading data.

Information is pre-recorded as follows: first, digital data is encoded into a 2D image, then the 2D image is translated into a hologram by CGH (Computer Generated Hologram) technology. Finally, the hologram is recorded as a sub-micron concave-convex pattern in each waveguide layer of the media. For data retrieval, a laser beam is focused at the end of a waveguide layer, then the light propagates in the waveguide and is scattered by the concave-convex pattern. The scattered light generates the 2D image on the plane parallel to the waveguide. This 2D image is captured by an image sensor and decoded into the original digital data.

An easy to produce medium with a high capacity, low power consumption, recyclable and without mechanics? Sounds not bad. Unfortunately, NTT said it is difficult to copy the media; but I guess they will find a solution for that too.