Jan 31, 2011 – Infrared (IR) microscopy has shown itself to be an important diagnostic tool for tissue analysis. To date, the main tool for performing IR microscopy has been the Fourier transform infrared (FTIR) microscope. FTIR microscopes utilize incandescent bulbs for light sources, and require cryogenically cooled detectors for the weak, optically poor probe signals. Image acquisition times can be tens of minutes even for sophisticated instruments, and the size and cost of FTIR microscopes precludes their broader clinical use. The development of broadly tunable, external cavity quantum cascade lasers (ECqcLâ„¢) has created an ideal light source for IR microscopy. Spectrally brilliant probe beams that are diffraction limited, with intensities many orders of magnitude higher than incandescent sources, can be generated from compact, room temperature ECqcLâ„¢ devices. Moreover, the increase in intensity allows the use of room temperature microbolometer focal plane arrays (FPAs) for detection. The combination of ECqcLsâ„¢ and microbolometer FPAs opens the possibility of producing low cost, compact, room temperature IR microscopes with acquisition speeds thirty times that of state-of-the-art FTIR microscopes. The present study explores the challenges of creating this new generation of IR microscopes, and demonstrates the capabilities of the technology.
Quantum cascade laser based replacement for FTIR microscopy