Information technology is an area of such broad importance
that almost all new methodologies fi nd uses. [1]
Most information derived from chemistry, and especially from some form of
analysis, proceeds by a path in which a sensor (e.g., an analytical
instrument) using electrical power generates information, which
is then encoded and transmitted in a separate step, again using
electrical power, to a separate unit, which may be local or distant, for processing and interpretation. We [2,3]
and others [4–7]
are
exploring schemes in which information is transmitted directly,
without using electrical energy. Such schemes have the potential to
be useful where electrical power is not reliably available or where
other constraints (e.g., size) argue for other types of solutions.