Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Measuring paper thickness fast and reliably

14.03.2016

The Fraunhofer Institute for Laser Technology ILT is unveiling its “bd-2” sensor for thickness measurements of paper and board webs. Within a measurement range of 8 millimeters, the system can accurately measure the thickness and embossed depth with a precision better than 200 nm. The small sensor head coupled with high-speed data processing facilitates inline measurements in the production line. At CONTROL 2016 in Stuttgart, Germany, visitors can experience the “bd-2” sensor live.

Materials and quality control must meet increasingly stringent requirements in the paper processing industry. To provide thickness measurement, for instance, sensors must now be accurate down to the sub-micron range yet nonetheless operate in the production line as fast as possible and with minimal maintenance.


Picture 1: The “bd-2” thickness measurement system based on bidirectional sensors.

© Fraunhofer ILT, Aachen, Germany.


Picture 2: Paper webs in production process.

© fotolia. Please note that this picture might only be used in connection with this press release.

To meet these requirements the optical thickness measurement system “bd-2” (for bidirectional measurements) was developed at Fraunhofer ILT. The sensor sends a measuring beam onto the material surface and the reflected signal allows the distance to be measured with a precision of 200 nm. The sensor has been previously used, e.g. for surveying cold-rolled metal sheets.

A special feature of the system is the 70 kHz sampling rate. This allows for an absolute and continuous measurement of the distance to the surface during running production. The thickness measurement system “bd-2” comprises two sensing heads mounted in a C-frame to measure the thickness of the product passing by.

“bd-2” is suited to measure the thickness of paper and board webs in the range of 10 µm to several millimeters. Untreated surfaces are measured as safe as painted, embossed, smoothed or supercalendered.

A new sensing head simplifies the entire measurement process

Compared with established methods – such as radiometric, capacitive or inductive methods – the new sensor offers several advantages:

Since irradiated and reflected beams are propagating along the same line, alignment efforts are eliminated as transmitter and receiver no longer have to be adjusted to each other.

To send and to receive the backscattered radiation only a small measuring head with a weight of 100 g is needed. It uses a small window with a 2 mm diameter, the cast protected by an air stream in harshest environments reliably against contamination. Compared with conventional sensors its spot diameter is about 100 microns, so that even the smallest structures can be detected.

Control processes safely

The new sensor »bd-2" provides the accuracy of interferometric measurement methods and is significantly faster than the established measurement technologies. The complete system processes up to 70,000 thickness readings per second. So, inline measurements are possible even at high product speeds that enable fast feedback loops to control and optimize production processes.

Sensor sets new standards for industrial manufacturing

In terms of speed and integrability, “bd-2” sets new standards for process control and quality assurance in various industry segments. The process paves the way for the transition from laboratory-based individual measurement to continuous inline production control. This is why the Fraunhofer ILT experts are targeting industry customers looking to meet higher accuracy requirements in series production, offering them not just complete systems but also extensive consulting in relation to process integration. The sensors were tested extensively in pilot plant operation, first industry partners have already carried out test runs with the system in their production lines.

Fraunhofer ILT at CONTROL 2016

The interferometric thickness sensor »bd-2« will be showcased at this year’s CONTROL in Stuttgart, Germany on the stand 1502of the Fraunhofer Alliance Vision in Hall 1.

Contact

Dr. Stefan Hölters MBA
Interferometrical Sensors
Telephone +49 241 8906-436
stefan.hoelters@ilt.fraunhofer.de

PD Dr. Reinhard Noll
Head of the Measurement
Technology and EUV Sources
Competence Area
Telephone +49 241 8906-138
reinhard.noll@ilt.fraunhofer.de

Weitere Informationen:

http://www.ilt.fraunhofer.de/en.html

Petra Nolis | Fraunhofer-Institut für Lasertechnik ILT

More articles from Machine Engineering:

nachricht Scientists from Hannover develop a novel lightweight production process
27.09.2017 | IPH - Institut für Integrierte Produktion Hannover gGmbH

nachricht PRESTO – Highly Dynamic Powerhouses
15.05.2017 | JULABO GmbH

All articles from Machine Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Nanoparticles help with malaria diagnosis – new rapid test in development

The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.

Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

Corporate coworking as a driver of innovation

22.11.2017 | Business and Finance

PPPL scientists deliver new high-resolution diagnostic to national laser facility

22.11.2017 | Physics and Astronomy

Quantum optics allows us to abandon expensive lasers in spectroscopy

22.11.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>