Recently developed mid-IR LEDs and diode lasers can be used to fabricate spectroscopic analyzers of a new generation. The LED-based design is advantageous, especially in process and portable instruments and fiber optic applications. The benefits are smaller instrument size, rugged operation without any moving parts, and high output pulse power. The availability of new ambient temperature operating LEDs based on A³B⁵ alloys in the spectral range of 2.8-4.7 micrometers and cooled diode lasers has made it possible to monitor several gases having strong absorption bands in this region. This paper briefly describes the properties and fabrication of infrared light emitting diodes and diode lasers by liquid phase epitaxy for emission wavelengths from 3.8 micrometers to 4.85 micrometers and 3-3.6 micrometers respectively. Some of the first applications of these LEDs and diode lasers in spectroscopic instrumentation (nondispersive CO₂ and fiber optic C_nH_m analyzers) are described.

Date Published: 20 September 1995
PDF: 7 pages
Proc. SPIE 2506, Air Pollution and Visibility Measurements, (20 September 1995); doi: 10.1117/12.221003

Published in SPIE Proceedings Vol. 2506:
Air Pollution and Visibility Measurements
Peter Fabian; Volker Klein; Maurus Tacke; Konradin Weber; Christian Werner, Editor(s)