Researchers at the Fraunhofer Institute for Applied Solid State Physics IAF have developed a spectrometer system based on a fast, tuneable quantum cascade laser (QCL) operating in the mid-infrared range. The whole wavelength range (4–12 μm) of the QCL emitter can be scanned within 1 ms. The QCL can be tuned to work at high scan frequencies or in a quasi-static mode over a wide wavelength range. This is achieved through the combination of QCLs in an external resonator with different MOEMS-based lattice scanners that work as wave-selective elements.
QCL-based measuring systems are well suited for quality control in a variety of industrial sectors, thanks to their ability to identify various chemical substances remotely and in real time. The compact design allows for the development of mobile, and even hand-held, measuring systems.