Large astigmatic laser cavity modes and astigmatic compensation

In this paper, it was experimentally verified that anisotropic (astigmatic) Hermite–Gaussian modes can be generated from a hemi-cylindrical cavity and can be transformed into Laguerre–Gaussian modes by using an extra-cavity plano-convex cylindrical lens which can modify different beam divergence angle in the x–z and y–z planes. By controlling the off-axis pumping and the angle of the extra-cavity cylindrical lens, a variation in laser patterns was observed. Moreover, several additional relationships under different conditions have been analyzed. All experimental results corresponding to the theoretical analysis, and the role of the hemi-cylindrical cavity can be completely understood by comparing the theoretical and experimental results.