Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


More rapid and efficient manufacturing of three-dimensional, transparent micro components

At the 2012 glasstec international trade fair, which will take place in Düsseldorf from October 23 to 26, the Fraunhofer Institute for Laser Technology ILT is presenting a laser manufacturing technique for structuring transparent materials at the joint Fraunhofer booth 15/E25.
Thanks to this technique, it is now possible for the first time to manufacture even assembled components made of transparent materials such as glass from a single block – with micrometer accuracy. In contrast to ablative techniques, in-volume selective laser etching (ISLE) is exceptional for its efficient use of material.

Fused silica tubes with a diameter of one millimeter and a wall thickness of nine micrometers, hole arrays with bore diameters of 50 micrometers, microfluidic components for medical diagnostics with channels that are less than 10 micrometers in diameter: the components used in precision mechanics, medical engineering, and metrology are getting smaller and smaller as their complexity increases.

Illustration of the size of an ISLE-manufactured micro gear wheel.

Picture Source: Fraunhofer ILT, Aachen/Volker Lannert

Take the example of the clock- and watchmaking industry, where so-called jewel bearings have to be precisely manufactured and subsequently mounted. At present, experienced specialists manually produce and mount these micro components by means of grinding and polishing, which takes a lot of time. Moreover, ablative techniques always entail a loss of material –typically as high as 80% – which can seriously impact costs depending on the specific material.

Given the tiny scale of micro components, transparent, i.e. “colorless”, materials are not amenable to manual processing, as the craftsman cannot see them well enough. Consequently, manufacturers revert to using rubies, which in addition to their hardness also have the advantage of being a red color that is easily visible.

In-volume selective laser etching speeds up the manufacturing process and removes the need for assembly

In cooperation with the Chair for Laser Technology LLT at RWTH Aachen University, a new laser manufacturing technique was developed at Fraunhofer ILT. The technique shortens the manufacturing process for micro components made from transparent materials and reduces the amount of material and energy used. Now the experts have applied in-volume selective laser etching (ISLE) to the manufacture of composite and assembled parts. This means there is no longer any need to adjust and assemble the individual components in micromechanical systems. The exposure time for a gear wheel already mounted on a shaft and fitted inside a housing is only around 15 minutes using the ISLE technique.
The process works as follows: using ultrashort pulsed laser radiation, a transparent work piece is exposed in the volume with 3D resolution at precisely the areas where material is to be removed. The material is chemically and physically changed and therefore gets selectively etchable. In the subsequent wet-chemical etching process, the exposed material is removed, while the unexposed material is scarcely affected by the etching process. This process makes it possible to manufacture micro channels, shaped holes, structured parts, and complex, composite mechanical components and systems. The ISLE technique can also be used for sapphire and glass as well as ruby. It is reproducible and ensures that components are geometrically identical in series production, while also offering a high degree of geometric and design freedom. Particularly impressive are its ability to produce shapes with micrometer accuracy, as well as kerfs and bores with extremely large aspect ratios, thanks to the small focus volume. The ISLE technique enables a level of material and energy efficiency that is simply not possible to obtain mechanically using even the most advanced ablative processes.

Scaling the laser manufacturing technique for industrial application

The main challenge facing the researchers in Aachen now consists in developing the ISLE technique so that it can be used by the manufacturers of micro components. “We are constantly working on improving the scalability of our technique so that a transfer from the lab to industrial-scale production can take place sometime in the future,” explains Dr. Dagmar Schaefer, group manager at Fraunhofer ILT. “The ISLE technique is individually adapted to the customer’s requirements according to the specific application. The biggest challenge for us is to achieve both the required component specifications and a sufficiently rapid structuring process at the same time.”
The exposure speed is currently several hundred millimeters a second. The goal is to increase this to several meters a second. At present, exposing a mounted gear wheel with a diameter of three millimeters would take 15 minutes; the higher exposure speed would reduce this time by a factor of 10.
In the medium term, efforts will be aimed at exploiting the potential of the technique within individualized mass production. This entails improvements to the present state of development that include increasing laser power and repetition rates and the use of faster beam deflection systems . ISLE promises greater cost-effectiveness and flexibility in the production of micro components in small and large batches, as well as in the mass production of individualized components.

Further Contacts

Dr. Dagmar Schaefer
Head oft he Group In-Volume Structuring
Phone +49 241 8906-628
Fraunhofer Institute for Laser Technology ILT
Steinbachstraße 15
52074 Aachen, Germany

Akad. Oberrat Dr. Ingomar Kelbassa
Acad. Director of the Chair for Laser Technology LLT at the RWTH Aachen University
Phone +49 241 8906-143
Fraunhofer Institute for Laser Technology ILT
Steinbachstraße 15
52074 Aachen, Germany

Axel Bauer | Fraunhofer ILT
Further information:

More articles from Trade Fair News:

nachricht Siemens expands motor portfolio for machine tools
06.10.2015 | Siemens AG

nachricht New 10.4" and 15.6" displays for Sinumerik 828 controls
05.10.2015 | Siemens AG

All articles from Trade Fair News >>>

The most recent press releases about innovation >>>

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

Im Focus: Kick-off for a new era of precision astronomy

The MICADO camera, a first light instrument for the European Extremely Large Telescope (E-ELT), has entered a new phase in the project: by agreeing to a Memorandum of Understanding, the partners in Germany, France, the Netherlands, Austria, and Italy, have all confirmed their participation. Following this milestone, the project's transition into its preliminary design phase was approved at a kick-off meeting held in Vienna. Two weeks earlier, on September 18, the consortium and the European Southern Observatory (ESO), which is building the telescope, have signed the corresponding collaboration agreement.

As the first dedicated camera for the E-ELT, MICADO will equip the giant telescope with a capability for diffraction-limited imaging at near-infrared...

Im Focus: Locusts at the wheel: University of Graz investigates collision detector inspired by insect eyes

Self-driving cars will be on our streets in the foreseeable future. In Graz, research is currently dedicated to an innovative driver assistance system that takes over control if there is a danger of collision. It was nature that inspired Dr Manfred Hartbauer from the Institute of Zoology at the University of Graz: in dangerous traffic situations, migratory locusts react around ten times faster than humans. Working together with an interdisciplinary team, Hartbauer is investigating an affordable collision detector that is equipped with artificial locust eyes and can recognise potential crashes in time, during both day and night.

Inspired by insects

Im Focus: Physicists shrink particle accelerator

Prototype demonstrates feasibility of building terahertz accelerators

An interdisciplinary team of researchers has built the first prototype of a miniature particle accelerator that uses terahertz radiation instead of radio...

Im Focus: Simple detection of magnetic skyrmions

New physical effect: researchers discover a change of electrical resistance in magnetic whirls

At present, tiny magnetic whirls – so called skyrmions – are discussed as promising candidates for bits in future robust and compact data storage devices. At...

Im Focus: High-speed march through a layer of graphene

In cooperation with the Center for Nano-Optics of Georgia State University in Atlanta (USA), scientists of the Laboratory for Attosecond Physics of the Max Planck Institute of Quantum Optics and the Ludwig-Maximilians-Universität have made simulations of the processes that happen when a layer of carbon atoms is irradiated with strong laser light.

Electrons hit by strong laser pulses change their location on ultrashort timescales, i.e. within a couple of attoseconds (1 as = 10 to the minus 18 sec). In...

All Focus news of the innovation-report >>>



Event News

EHFG 2015: Securing healthcare and sustainably strengthening healthcare systems

01.10.2015 | Event News

Conference in Brussels: Tracking and Tracing the Smallest Marine Life Forms

30.09.2015 | Event News

World Alzheimer`s Day – Professor Willnow: Clearer Insights into the Development of the Disease

17.09.2015 | Event News

Latest News

NASA provides an infrared look at Hurricane Joaquin over time

08.10.2015 | Earth Sciences

Theoretical computer science provides answers to data privacy problem

08.10.2015 | Information Technology

Stellar desk in wave-like motion

08.10.2015 | Physics and Astronomy

More VideoLinks >>>