Measurement and compensation of wavefront deformations and focal shifts in high-power laser optics

K. Mann; B. Schäfer; M. Stubenvoll; K. Hentschel; M. Zenz

doi:10.1117/12.2196160

Translator Disclaimer

23 November 2015 Measurement and compensation of wavefront deformations and focal shifts in high-power laser optics

K. Mann, B. Schäfer, M. Stubenvoll, K. Hentschel, M. Zenz

Author Affiliations +

Proceedings Volume 9632, Laser-Induced Damage in Optical Materials: 2015; 96321D (2015) https://doi.org/10.1117/12.2196160
Event: SPIE Laser Damage, 2015, Boulder, Colorado, United States

Abstract

We demonstrate the feasibility of passive compensation of the thermal lens effect in fused silica optics, placing suitable optical materials with negative dn/dT in the beam path of a high power near IR fiber laser. Following a brief overview of the involved mechanisms, photo-thermal absorption measurements with a Hartmann-Shack sensor are described, from which coefficients for surface/coating and bulk absorption in various materials are determined. Based on comprehensive knowledge of the 2D wavefront deformations resulting from absorption, passive compensation of thermally induced aberrations in complex optical systems is possible, as illustrated for an F-Theta objective. By means of caustic measurements during high-power operation we are able to demonstrate a 60% reduction of the focal shift in F-Theta lenses through passive compensation.

Citation Download Citation

K. Mann, B. Schäfer, M. Stubenvoll, K. Hentschel, and M. Zenz "Measurement and compensation of wavefront deformations and focal shifts in high-power laser optics", Proc. SPIE 9632, Laser-Induced Damage in Optical Materials: 2015, 96321D (23 November 2015); https://doi.org/10.1117/12.2196160

ACCESS THE FULL ARTICLE