How Chemometrics Turns NIR Spectra into Results
NIR spectra contain broad, overlapping absorption features rather than simple isolated peaks. Chemometric calibration is used to interpret this complex spectral information and link it to the property being measured.
A calibration model is built using representative samples that have been analysed by a reliable reference method. The NIR spectra and reference results are then used to create a model that can predict results for similar unknown samples.
The quality of the calibration controls the reliability of the NIR result. A good model should include the expected range of sample variation, including composition, moisture, particle size, temperature, and presentation conditions. Models also need validation to confirm they perform reliably on real samples, not only on the calibration set.
Building Confidence in NIR Calibration
For more detail on the measurement principle, review PAS’s overview of Near Infrared Spectroscopy technology. To compare suitable systems, explore PAS’s NIR analysers through Portable Analytical Solutions, or get in touch to discuss calibration models, reference data, and application requirements.