Infrared sensors

Infrared transmission / reflection – Measurement of moisture, basis weight, thickness

By means of optical evaluation of the reflected light energy in the near-infrared range (NIR), important product-specific parameters such as moisture (water), coating weight, thickness, and organic components in the web can be measured during the manufacturing process.

Its non-nuclear measurement technique is very selective and offers an accurate and cost-effective measurement solution that can be supplied in either single-sided reflection, or dual-sided transmission modes.

Infrascope NIR

Measurement of basis weight (mass per unit area) / moisture

Absorption of infrared light

The Infrascope NIR monitors the absorption of infrared energy of all components on or in the web in the near infrared range. Measuring over the entire spectrum range and applying multivariate data analysis tools produces highly accurate calibration results from information in redundant spectra.

The Infrascope NIR is available in transmission and reflexion mode.

Product Highlights

  • Non-nuclear
  • Contactless, non-destructive
  • Intelligent sensor with fast onboard micro processing

Customer benefits

  • Non-destructive, continuous discrimination between multiple components
  • High measuring accuracy
  • Improved process understanding through online NIR spectral measurements

Contactless and continuous monitoring of all quality parameters with highest accuracy is extremely important for all web producing industries. The Infrascope NIR – Sensor can be widely used in pulp & paper manufacturing, the plastic film & extrusion industry as well as in the coating & converting sector.


  • By simultaneously analyzing the entire NIR Spectrum, the sensor is able to discriminate between multiple components in the web.
  • Due to very high spectral resolution, the sensor can distinguish between components with nearly similar, but not identical, IR absorption.
  • Improved process understanding by on-line NIR spectral measurements and use of multivariate calibration modeling.
  • Reduction of waste and reworking through increased quality attribute measurements and optimized process control

NIR-T (Transmission): To measure the entire thickness of the product web
NIR-R (Reflection): To measure coatings

ParameterBasis weight & MoistureBasis weight 
Spectral range900 - 2200900 - 1700nm

Measuring range
Transmission 1

Basis weight1 - 3001- 300g/m²
Moisture0 - 15-% H2O
Measuring range
Reflexion 1
Basis weight1 - 601 - 60g/m²
Moisture0 - 15-% H2O

1) Measuring range and measuring accuracy depending on the material (analysis of material sample necessary)