Reversible optical switch.

Researchers at the Georgia Institute of Technology, in a program sponsored by the National Science Foundation, are developing. a light-activated optical switch that eventually could be the basis for a new type of rewritable three-dimensional data storage system. By using a small number of "trigger molecules" to induce a phase transition in liquid crystal materials, the system would write, read, and erase information using different forms of polarized and unpolarized light.

This type of optical storage system would offer major advantages over conventional computer floppy disks, magnetic tape, and compact discs, which use two-dimensional media to store data. The optical …