Feature Articles

Group to set guidelines for transfer of optical data

Recognizing that existing computer data transfer formalisms such as IGES were not suitable for optical data transfer, the International Standards Organization (ISO) set up a task group late last year to develop standards related to the digital transfer of optical data.

by Robert E. Parks
High power, coherent laser diodes

Many of the growing number of applications for laser diodes have appeared due to the increased power available from today's sources. Prior to 1981, the highest reported cw output power was a few hundred milliwatts, while today cw powers of over 50 Watts are being reported. The applications that have resulted from this technological leap include efficient diode pumped solid state lasers, pyrotechnic initiation, night illumination, satellite communication, read/write optical discs, and direct doubling of diode radiation into the blue. To continue this rapid growth in the application base, researchers have pursued several directions including development of higher power lasers and the development of high power coherent lasers emitting in a single Gaussian beam.

by David Welch, William Streifer, and Donald Scifres