QCLs represent an important advance in MWIR and LWIR laser technology. With the demonstration of
CW/RT QCLs, large number applications for QCLs have opened up, some of which represent replacement of
currently used laser sources such as OPOs and OPSELs, and others being new uses which were not
possible using earlier MWIR/LWIR laser sources, namely OPOs, OPSELs and CO2 lasers.
Pranalytica has made significant advances in CW/RT power and WPE of QCLs and through its invention of a
new QCL structure design, the non-resonant extraction, has demonstrated single emitter power of >4.7 W
and WPE of >17% in the 4.4μm-5.0μm region. Pranalytica has also been commercially supplying the highest
power MWIR QCLs with high WPEs. The NRE design concept now has been extended to the shorter
wavelengths (3.8μm-4.2μm) with multiwatt power outputs and to longer wavelengths (7μm-10μm) with >1 W
output powers. The high WPE of the QCLs permits RT operation of QCLs without using TECs in quasi-CW
mode where multiwatt average powers are obtained even in ambient T>70°C. The QCW uncooled operation
is particularly attractive for handheld, battery-operated applications where electrical power is limited.
This paper describes the advances in QCL technology and applications of the high power MWIR and LWIR
QCLs for defense applications, including protection of aircraft from MANPADS, standoff detection of IEDs, insitu
detection of CWAs and explosives, infrared IFF beacons and target designators. We see that the SWaP
advantages of QCLs are game changers.