Proceedings Article | 18 May 2012
R. Linares-Herrero, G. Vergara, R. Gutiérrez-Álvarez, C. Fernández-Montojo, L. Gómez, V. Villamayor, A. Baldasano-Ramírez, M. Montojo
KEYWORDS: Near infrared spectroscopy, Spectroscopy, Infrared spectroscopy, Absorption, Staring arrays, Mid-IR, Spectroscopes, Sensors, Gases, Optical filters
MWIR spectroscopy shows a large potential in the current IR devices market, due to its multiple applications (gas
detection, chemical analysis, industrial monitoring, combustion and flame characterization, food packaging etc) and its
outstanding performance (good sensitivity, NDT method, velocity of response, among others), opening this technique to
very diverse fields of application, such as industrial monitoring and control, agriculture, medicine and environmental
monitoring.
However, even though a big interest on MWIR spectroscopy technique has been present in the last years, two major
barriers have held it back from its widespread use outside the laboratory: the complexity and delicateness of some
popular techniques such as Fourier-transform IR (FT-IR) spectrometers, and the lack of affordable specific key elements
such a MWIR light sources and low cost (real uncooled) detectors. Recent developments in electrooptical components
are helping to overcome these drawbacks. The need for simpler solutions for analytical measurements has prompted the
development of better and more affordable uncooled MWIR detectors, electronics and optics.
In this paper a new MWIR spectrometry device is presented. Based on linear arrays of different geometries (64, 128 and
256 elements), NIT has developed a MWIR Variable Filter Array Spectrometer (VFAS). This compact device, with no
moving parts, based on a rugged and affordable detector, is suitable to be used in applications which demand high
sensitivity, good spectral discrimination, reliability and compactness, and where an alternative to the traditional scanning
instrument is desired. Some measurements carried out for several industries will be also presented.