Time-resolved microscopy of the absorption of ultrashort laser pulses inside glass permits customized interaction - precise separation even of hardened glasses

The use of ultrashort laser pulses with a duration from a few picoseconds to femtoseconds opens up new fields of application in glass processing. Even substrates can be processed now, which are

new ways in glass processing - klaus bergner
Presentation of the research results at the conference CLEO 2016

problematic to treat conventionally, e.g. by sawing or CO2 laser processing. For example, chemically hardened glass, which is used for mobile electronic devices (i.e. smartphone, tablet), or ultra-thin samples (<100 microns) can be precisely separated. However, this requires a fundamental understanding to control the highly nonlinear interaction process.
The analysis and control of these processes is one of the sub-goals of the joint research project "ScULP³T - Scaling Ultrafast Laser Productive Precision Processing Technology", which is supported by the BMBF within the framework of the research initiative "EffiLAS - Efficient high-performance laser beam sources". In this project, the companies TRUMPF Laser GmbH, Robert Bosch GmbH and SCHOTT AG, but also the Institut für Strahlwerkzeuge at the University of Stuttgart and the Ultrafast Optics group at our Institute are involved. The main objective is to realize ultrafast lasers with an average power of up to 2 kW and to employ these pulses for different applications.
At the IAP a novel time-resolved microscopy method was to set up, which provides insight into the complex interaction physics in order to analyze and tailor these processes. First results have been presented und discussed in an invited lecture by Klaus Bergner during one of the world's largest photonics conferences, the CLEO in the United States. In particular, the laser-induced plasma formation and relaxation as well as the resulting material changes have been in the focus of the investigations. Fundamental processes have been identified, which lead to the formation of color centers as well as stress inside the sample. This enables customized separation of the glass.
However, the full potential of this approach has not yet been exploited by far. Further investigations will include beamshaping strategies to improve the control on stress formation. The aim is to develop a flexible approach leading to increased productivity, which will foster a transfer of this technology into production.

Measured electron density inside the glass after irradiation with ultrashort pulses
Measured electron density inside the glass after irradiation with ultrashort pulses


M.Eng. Klaus Bergner

Phone: +49(0)3641 | 9-47815

Prof. Dr. Stefan Nolte

Phone +49(0)3641 | 9-47820

News from: 04.10.2016 14:06
back | next