Optoscope WLI

Measurement of thickness / layer thicknes

White light interference

White light from the upper and lower boundary surfaces of thin films is reflected differently. Interference measurement allows for the precise measuring of transparent coatings on films and mono-films. Both, the layer thickness and film thickness can be determined with a special measuring process.

Principle of operation

When white light is reflected from thin layers, this reflection appears colorful like a rainbow. This effect can be observed for example in a thin film of oil on a puddle of water. The light is reflected at both the upper and lower boundary of the part. The superimposed reflections interfere. The interference is related to the layer thickness and can be detected by a spectrometer.

Using this method, mono layers and transparent coatings on film can be measured precisely. By a special measuring procedure, both the layer thickness and the film thickness can be determined accurately on-line.

Product highlights

  • Simple and rapid measurement method
  • Measures coating thickness and film thickness
  • High accuracy and durability

Customer benefits

  • Quick process optimization
  • Material savings
  • Quality assurance

Area of application

  • Mono layers
  • Transparent coatings on film
We hire!


Techtextil Logo

Exhibition for Technical Textiles & Nonwoven
14 - 17 May 2019
Frankfurt, Germany
Visit us at booth no. 3.0 B42!

Opens external link in new window


Chinaplas Logo

Exhibition for Plastic & Film
21 - 24 May 2019
Shanghai, China
Visit us at booth 5.1 S01!



Key-Exhibition for Garment & Textile Machinery
20 - 26 Jun 2019
Barcelona, Spain
Visit us at booth no. H2-C203!


Mahlo GmbH + Co. KG • Donaustraße 12 • 93342 Saal /Donau
Tel.: +49-9441-601-0 • info@mahlo.com