laser diode A type of light source that resembles a light-emitting diode (LED) in structure, although much more difficult and expensive to manufacture, much less durable, and much more capable. Laser diodes are associated with more expensive and complex supporting electronics, but generally have much faster cycle times and, therefore, offer much more bandwidth. Diode lasers offer significant mechanical and 74570c12.qxd 9/11/07 12:25 PM Page 281 |