Under the umbrella of the SPIE, top-class symposiums are being held annually.
The scientific elite met at the Laser Damage Symposium in Boulder to discuss trends and developments with young and creative students and industrial representatives. We were there, too!
The conference was hosted under the scientific direction of employees from such renowned institutions as, for example, Lawrence Livermore National Labs in the U.S.A. and LZH in Germany. The organizational committee welcomed 128 participants from Europe, Asia, and America. Laser Components supported the symposium and was the only German company to actively participate by holding a presentation.
Over ninety presentations were held during the course of the three-day conference, divided into three blocks of content:
Coating Impurities
The first session entitled “Surfaces, Mirrors, and Contamination” focused on coating and substrate impurities, which is an issue for many manufacturers. Exceeding existing critical defect sizes (~ 1 µm) leads to a significant reduction in the laser-induced damage threshold. Of course, this has consequences in industrial production. It is particularly important to review the necessity of cleanroom conditions in substrate production.
Increasing Damage Thresholds
The second session entitled “Thin Films” dealt with the extensive field of thin film systems and their resistivity to laser radiation. A striking number of contributions were dedicated to the distribution of the electrical field within a coating system. In many of the contributions, an adjustment of the coating thickness led to the generation of an optimized field distribution and ultimately increased the damage threshold. The following successes were achieved: Adjusting the four top-most highly-refractive layers, the damage threshold was increased from 20 J/cm² to 30 J/cm². However, this is still a theoretical model. Just as many cases were reported in which a supposed optimization actually led to a reduction in the laser damage threshold.
Alternative Measurement Methods
In the third session entitled “Fundamental Mechanics,” alternative measurement methods and measuring setups were introduced that incorporate the approach specified in ISO21254. This norm contains fundamental guidelines regarding assembly, implementation, and analysis of a measurement. The goal is to use as uniform a method as possible to determine the laser damage threshold in order to be able to better compare the results. During the symposium, it became apparent that industrial manufacturers are currently implementing their own measuring stations. Laser Components is also working on developing its own measurement technology.
