SHEDS, Part II

Breck Hitz, Senior Technical Editor

This month, we complete our report on the Defense Advanced Research Projects Agency’s Super-High Efficiency Diode Sources (SHEDS) program. In the introduction to last month’s articles, we related that, although this program was undertaken for the benefit of the military, it would have an enormous effect on the commercial laser market.

Its goal is to increase the electrical efficiency of laser diodes from the current maximum of 50 percent to 80 percent — or to decrease the wasted energy from 50 percent of the input energy to 20 percent.

Because diode lasers and diode-pumped lasers account for somewhere between half and three-quarters of the world’s laser sales, it is hard to overestimate the impact that the program will have on the commercial marketplace.

Last month, we brought you reports from the seven original SHEDS contractors. Since the program started, the Defense Advanced Research Projects Agency has expanded it to include an investigation of vertical-cavity surface-emitting lasers. This month, scientists at Novalux Inc. in Sunnyvale, Calif., and at Princeton Optronics Inc. in Mercerville, N.J., describe their respective attempts to meet the program’s goals using such lasers.