Highly efficient laser bars developed for materials processing
Infrared laser bars for materials processing with exceptional efficiency and power have been developed as part of the research project ‘EKOLAS’.
The project, which concluded in February and was funded by the German Federal Ministry of Education and Research (BMBF), featured partners Osram Opto Semiconductors, Laserline, Heraeus, Fraunhofer ILT, Fiberware and Welser Profile.
The partners are part of the EffiLAS (efficient high-power laser beam sources) association, which is focussed on optimising the performance and energy efficiency of laser light sources for applications in production, measurement technology or environmental and life sciences.
The newly developed laser bars have a maximum output of 400W in continuous-wave operation. When operated at 300W, the bars achieve an efficiency of about 70 per cent in the wavelengths of 1,000 and 1,020nm.
This compares to the 200W bars operating at 63 per cent efficiency that were achievable 10 years ago, and the 250W bars operating at around 60 per cent efficiency achievable five years ago, according to the project partners, who explained that the output power of these laser technologies were limited by conversion efficiency and cooling at the time.
The partners were able to draw on experience gained in other ventures under the EffiLAS umbrella organisation, including an understanding of materials science and simulation in the field of epitaxy, as well as fundamental expertise in chip and facet technologies.
‘We are very excited to achieve, and in some cases even exceed, all of our targets in this project,’ remarked Sebastian Hein, EKOLAS project manager at Osram Opto Semiconductors. ‘The key to success was the development of innovative software tools for simulating the electro-optical properties of the lasers, which take into account the thermal distribution, temperature-dependent material properties and mode-dependent wave propagation in the resonator. These tools considerably accelerated and simplified the necessary test runs, making a fundamental contribution to the results of the project.’
The newly gained knowledge from the simulation of certain processes can now be transferred to other product groups and wavelengths in the range between 800 and 1,060nm, according to the partners. In addition to the advantages in product development, they say the results also strengthen and consolidate the establishment of supply chains in Germany and the rest of Europe.