Short range spectral lidar using mid-infrared semiconductor laser with code-division multiplexing technique

Summary form only given. A short-range spectral lidar based on the code-division multiplexing (CDM) architecture using mid-infrared Sb semiconductor lasers for remote sensing has been demonstrated with near detector-limited performance. The system principle is similar to optical-CDMA for communications and applicable to any number of wavelengths, but was demonstrated with two wavelengths similarly to conventional DIAL (Powers et al, Appl. Opt. vol. 39, pp. 1440-1448, 2000; McRae and Kulp, Appl. Opt. vol. 32, pp. 4037-4050, 1993). An experiment using <20-mW transmitter average power could detect an open-air acetylene gas leak from 10 m away with dynamic, random, noncooperative backscatters. We believe this is among the first demonstrations of this semiconductor spectral lidar with orthogonal CDM architecture, as well as the first demonstration of mid-IR Sb lasers used in open path, noncooperative target remote sensing.