Near infrared (NIR) fiber optic spectroscopic analyzers are being used widely in the process industry. One of the long- standing issues with such analyzers is the ability to transfer calibrations from one analyzer to another and from an analyzer to itself after repair. The most frequently services parts of a spectrometer are the lamp and the probe. This paper will examine calibration issues related to probe design, probe to probe uniformity, and the interaction of the probe, spectrometer and fiber combination. Specifically, what impact does transmission, spectral features, vibration sensitivity, pathlength, window wedging, and other probe characteristics have on the spectroscopic system performance and transferability.
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