Understanding Spectral Properties in Pyrometry: Why Wavelength Matters for Accurate Temperature Measurement
In infrared temperature measurement, the spectral properties of a pyrometer play a crucial role in determining accuracy and reliability. Spectral properties refer to the specific wavelengths of infrared radiation that a pyrometer detects and measures. Different materials emit thermal radiation differently across wavelengths, and the sensor’s spectral response must match the material’s emissivity characteristics to ensure precise readings.
Understanding these spectral interactions is essential for selecting the right pyrometer for your application. This article provides an overview of spectral properties and explains how they affect temperature measurement accuracy. Following this, we’ll compare the spectral characteristics of two popular models — the A5 and A250 pyrometers — to help you choose the optimal sensor for your industrial needs.
Infrared Pyrometer Spectral Comparison: Choosing the Right Sensor for Accurate Temperature Measurement
In-Depth Breakdown: Explaining the Infrared Pyrometer Spectral Comparison Video
Spectral properties in the near-infrared range A5-IN and A250
A250
-The spectral sensitivity of the A250 pyrometer is the spectral properties superposition for two components:
-Spectral sensitivity of InGaAs -1.7mkm photodetector and cutting filter 1400nm.
-The short wavelength limit created by the multiplication of two curves, and its 5% cut-off is near 1.38-1.4mkm.
-The photodetector long wavelength limit determines extended wavelength limit is 1.7mkm, But the effective wavelength of the superposition is about 1.6mkm ±30nm. This value is mentioned in the pyrometer specification.
Sample of spectral response
The spectral sensitivity after the above superposition of the A250 pyrometer
Optical scheme of dual wavelength pyrometer A5-IN
Pyrometer A5-IN filters specification
BBP-1080-1430nm
- CWL=1300nm±30nm
- Cut on 5%: 1080±50nm
- Cut off 5%: 1430±50nm
- Blocking 300-1000 and 1600-2000nm with OD≥3
- HWL ≥ 300nm (filter width on 50% of maximal transmission)
- List Item #1
BP 1600-90 nm
- CWL =1600nm ± 20nm
- Cut on 5%: 1910±75nm
- Cut off 5%: 1430±50nm
- HWL ≥90-100nm (filter width on 50% of maximal transmission)
- Average transmittance: >70%
- Blocking 300-1830 with OD ≥3
