High-order wavefront aberrations due to a laser-induced breakdown spark in still air

Appl Opt. 2020 Sep 1;59(25):7510-7520. doi: 10.1364/AO.396217.

Abstract

Experimental measurements of the wavefronts of the light from a laser-induced breakdown (LIB) spark in stationary air are presented for the full range of angles between the LIB laser and wavefront sensor up to 90°. The wavefront data are compared to measurements of the spark shape and position acquired from simultaneous photographic images of the spark. The results show that the aberrations from the LIB spark appear primarily as two modes determined from proper orthogonal decomposition, with the amplitude and importance of the modes depending on system parameters and viewing angle. Data are also presented demonstrating the link between the spark wavefront and the spark shape, and conclusions are drawn regarding how to minimize the spark aberrations for optical systems in which the spark is used as a light source to measure optical wavefronts.