BLOCKS of glass may soon replace the electrical switchgear that handles
fibre-optic signals in telephone exchanges. Researchers at Harvard University
say they can burn “waveguides” into blocks of glass, forming the equivalent of
wires to carry light around optical circuits.
Optical fibres can carry many telephone conversations and other streams of
data at once by encoding each stream on different wavelengths of light. To
redirect the data at an exchange, these data streams have to be split up and
processed. Because there aren’t any circuits that can do this optically, the
signals must be converted into electrical pulses, processed electronically,…
