High-radiance light-emitting diodes

The properties of Al
x
Ga
1-x
As heterojunction incoherent edge emitters are described. Single (SH) and double-heterojunction (DH) diodes emitting at about 8200 Å were studied. The highest CW radiance measured perpendicular to the emitting facet was 95 W/cm
²
.sr at 4200 A/cm
²
for a stripe-geometry SH device. This high radiance level was found to be consistent with an operating life of many thousands of hours. The near- and far-field patterns of the diodes are presented as well as the spectral characteristics and the radiance as a function of drive current, both pulsed and dc.