When analyzing combustion events of energetic materials it is important to be able to determine reaction paths and local temperatures occurring during the reaction. Thus far, energetic diagnostics have primarily focused on collecting data in the visible region of the spectrum using optical spectroscopy techniques. The infrared region of the spectrum provides significant advantages because many important combustion intermediates have strong ground state vibrational transitions in the infrared that cannot be seen in the visible. Currently, the primary method of infrared spectroscopic measurements is through the use of Fourier transform infrared spectroscopy (FTIR). This method is restricted in temporal resolution which limits the method's utility in highly transient energetic applications. In this paper, an infrared echelle spectrometer is presented that is well suited for spectroscopic measurements of energetic materials. The spectrograph is used in conjunction with a Sofradir HgCdTe infrared image sensor and can be used for emission and absorption spectroscopic measurements in the 1-5 micron wavelength range. The echelle design permits a large spectral range (～2 μm) that cannot be achieved using rapid-scan Fourier transform infrared spectroscopy while maintaining a relatively high resolution of approximately 1 nm over the entire spectral range. The spectrometer was validated using the infrared absorption spectra of a known species in a gas cell.
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