DISPLAY AND RECORDING OF SPATIALLY AND SPECTRALLY RESOLVED NEAR-FIELD PATTERNS OF LASER DIODES.
The described experimental setup provides the experimenter with spatially and spectrally resolved near-field emission patterns of laser diodes. For the detailed investigation of laser modes, high spectral and spatial resolution are required. Some applications are described. A significant difference was observed for instance in the lateral modal patterns of mesa and stripe-geometry diodes; a relation was noted between changes in modal patterns and the appearance of kinks in the P//L-I characteristic. Aging usually caused a significant spectral broadening and changes in the modal pattern.