Inline-Measurement Technology

Our range of services

In the Fourth Industrial Revolution, networked technologies are on the rise, thus increasing the amount of data that needs to be processed quickly and inline. In production metrology, the importance of real-time signal processing, in particular, is increasing.

In this context, Fraunhofer ILT is developing absolute measurement interferometric sensors for inline use which make it possible to record geometric features of an object without contacting it. Sensors developed to date have measurement ranges of up to 20 mm, achieve measurement accuracies of less than 1 μm and operate at measurement frequencies of up to 80 kHz; the continuously generated data volume is processed in the measurement cycle to determine distances or thicknesses. FPGA (field-programmable gate arrays) modules are used for uninterrupted processing of large amounts of data. They can be used to parallelize and accelerate computationally intensive operations, and their processing clock is accurate down to nanoseconds.

Initial applications include the autofocusing of laser machining processes and the control of cold rolling processes in metal processing. Fraunhofer ILT has developed robust sensors with up to four independent measuring arms for laser welding or laser material deposition, among others, and which can be individually adapted to applications. Available measuring wavelengths are, for example, in the ranges around 835 nm, 1 μm and 1.5 μm.

The range of services we offer includes feasibility studies for customers’ specific tasks, the development of new processes, components and equipment, and individual consulting.

Robust thickness measurement system »bd-2« (two interferometric sensors and a C-frame).
© Fraunhofer ILT, Aachen, Germany.
Robust thickness measurement system »bd-2« (two interferometric sensors and a C-frame).
»bd-4« sensor and FIRE data processing electronics with fiber optic measuring arm (yellow).
© Fraunhofer ILT, Aachen, Germany.
»bd-4« sensor and FIRE data processing electronics with fiber optic measuring arm (yellow).
3D detection of parts on a belt.
© Fraunhofer ILT, Aachen, Germany.
3D detection of parts on a belt.

Measurement of Geometric Dimensions

  • Laser-measurement processes (interferometry, triangulation) for measuring distances and thicknesses
  • Absolute-measuring interferometric sensor technology (»bd-x«)
  • Optical coherence tomography (OCT)
  • Applications in manufacturing and process control and integration into control loops
  • Inline monitoring and control of laser manufacturing processes (cladding, welding depth, surface structures, drilling, additive manufacturing)

Chemical Analysis

  • Spectroscopic measurement technology, laser-induced breakdown spectrometry (LIBS)
  • Process analysis of metals, ceramics, glass, slag, raw materials, dust
  • Analytics for mechanical recycling, automated sorting processes
  • Positive material identification (PMI): 100% inspection of semi-finished and finished products in the production line
  • Spatially resolved elemental analysis; purity analysis of production samples, micro-inclusions and segregations in metals


  • Opening up new fields of application for laser measurement technology
  • Evaluation models and prototypes for industrial applications
  • Customer-specific systems for measuring tasks in production


Laser technology can solve demanding tasks in many different industries. Whether as a tool in automotive production, as measuring equipment in the environmental sector, as a diagnostic or therapeutic instrument in medical technology or as a communication medium in space technology, the laser provides multiple uses with high productivity and high efficiency.

Read up about the innovations of the Fraunhofer ILT in a few selected industries and convince yourself!


Research with us!

Please do not hesitate to contact us if you have any questions about general topics! Our contact persons are happy to get in touch with you.


Donges, A., Noll, R.:
Laser Measurement Technology
Heidelberg [u.a.]: Springer 2015,
Springer Series in Optical Sciences,
Vol. 188. ISBN 978-3662436332

Noll, R., Hölters, S., Kämmerling, J., Lenenbach, A.:
Laserabstandssensoren messen die Dicke von Walzbändern
QZ 58 (10), 44-47 (2013) 

Sturm, V., Eilers, D., Werheit, P., Chiarotti, U., Volponi, V., De Miranda, U. Zani, M., Makowe, J.:
Elemental monitoring of steel scrap loading an electrical arc furnace
Metallurgical Analysis,  Vol. 32 (6): 18-23

Hölters, S., Overbeck, J., Ederleh, L., Michaeli, W., Lenenbach, A., Noll, R.
Präzise Messtechnik für komplexe Mehrschichtfolien
Coating Int. 43, Nr 9, 6-12

R. Noll, M. Krauhausen
Online laser measurement technology for rolled products
Ironmaking & Steelmaking
35, 221-227, 2008

R. Noll, M. Krauhausen
Online Lasermesssysteme für die Stahl- und Automobilindustrie
Düsseldorf: VDI 2008
VDI-Berichte. Bd 2011
pp. 3-12

R. Noll, M. Krauhausen
Online-Prüfung von Bändern und Rohren
Bänder Bleche Rohre
49, 72-75, 2008

A. Lenenbach, S. Hölters, R. Noll
Optisches Online-Messverfahren zur Überwachung von Wandstärken an Stückgütern in der kunststoffverarbeitenden Industrie
2011, 33-41, 2008

R. Noll, M. Krauhausen
Autoteile unter Laseraugen
Laser + Photonik
2, 30-33, 2007

R. Noll, M. Krauhausen
Den Bewegungszustand des Blechs einfrieren
QZ Qualität und Zuverlässigkeit
52, 36-40, 2007

R. Noll
In: Handbuch zur Industriellen Bildverarbeitung. Hrsg.: N. Bauer. Fraunhofer IRB Verl.
56-60, 2007

R. Noll, M. Krauhausen
Lasertriangulation für die Online-Messung geometrischer Größen in der Produktion
In: Handbuch zur Industriellen Bildverarbeitung. Hrsg.: N. Bauer. Fraunhofer IRB Verl.
260-275, 2007

R. Noll, M. Krauhausen
Online-Lasermesstechnik für Walzprodukte
stahl und eisen
127, 99-105, 2007

Our services cover a wide range of topics. Related topics and further research and development projects can be found under the following links.