Why NIR and XRF Measure Different Information
Near-infrared spectroscopy works by measuring how a material absorbs, reflects, or transmits near-infrared light. The spectral response comes from molecular vibrations, especially bonds involving hydrogen. This makes NIR useful for many organic materials, moisture-related measurements, polymers, food products, agricultural materials, pharmaceuticals, and some minerals.
XRF works differently. It excites atoms in the sample and measures the characteristic X-rays emitted by each element. This allows XRF to identify and quantify many elements directly, including metals and other inorganic elements.
Because NIR does not measure atomic emissions, it cannot report elemental concentrations in the same way as XRF. NIR may detect properties that correlate with composition when a validated calibration model exists, but it should not be treated as a direct elemental analysis technique.
Choosing the Right Method for Composition Testing
For more detail on the method, review PAS’s overview of Near Infrared Spectroscopy technology. To compare suitable systems, explore PAS’s NIR analysers through Portable Analytical Solutions, or contact our team to discuss whether NIR is suitable for your material and measurement objective.