Non-Dispersive Infrared Spectroscopy
(NDIR Spectroscopy)

NDIR spectroscopy as a physical sensor principle is an established procedure in the sensor field to highly selectively and stably determine concentrations and compositions of materials. InfraTec produces various single channel sensors for analytical instruments and spectrometers.

Infrared Detectors for Narrowband Sources

High-quality lithium (LiTaO3) is an extremely powerful pyroelectric that is also less expensive than other thermal sensors. Through a special metal black layer, the infrared sensor absorbs radiation extremely uniformly over a very wide wavelength range from 2 µm to over 20 µm. The sensor does not require cooling and ensures short reaction times for modulation frequencies up to a few kilohertz.

Detectors for Infrared Spectroscopy with an Integrated Fabry-Pérot Filter

Gases such as hydrocarbons have very closely spaced absorption bands. Therefore, a measurement requires precisely defined narrow bandpass filters. However, unknown gases can not be measured with these filters. This is instead achieved by a tunable filter. With its help, more gases can be measured by a detector. For this purpose, a Fabry-Pérot interferometer (FPI) is integrated into a pyroelectric detector (FPI-Detector). This combination of the FPI detector is particularly advantageous since it can be used for almost all wavelength ranges and does not need to be cooled. The entire assembly is so small that it fits along with a signal preamplifier in a TO8 housing.

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United States

InfraTec infrared LLC
Sales Office

5048 Tennyson Parkway

Suite 250

Plano, TX 75024


Los Angeles, CA - Sales Office


Further Applications of FPI Detectors

  • Environmental and climate research: measurement of emissions, identification of plastics in waste sorting, leak detection on supply lines, composition of the atmosphere
  • Measurement on surfaces: detect contaminants, ensure complete coating with lubricants, determine the type and thickness of coatings
  • Identification of solids
  • Identification of impurities or counterfeits

Find Out More About Our Pyroelectric Detectors

Detector Search

InfraTec offers five different product groups including approximately 50 standard pyroelectric detectors. Choose your suitable infrared detectors with the help of our detailed detector search.

Overview of all standard infrared detectors
Sensor division InfraTec detectors overview