Optics and Photonics Society of Iran

In thin-disk MOPA laser a seed laser beam is propagated through a pumped thin-disk for power scaling. Since the disk active material is very thin, it is necessary to reimage the laser beam for several times onto the thin-disk to enhance the amplification coefficient. This requires an optical multi-pass system. The main feature of multi-pass is forming unique spot size on the disk at each pass. In this paper the scientific report of designing and analyzing an eight passes optical system is presented. At first, the optical and mechanical consideration are extracted and then a numerical code is developed to obtain the eight-passes parameters. Due to examining and analyzing the designed optical system, it is simulated by Zemax and Oslo optical software. Spot size of beam onto the different optical elements and astigmatism aberration as well as beam specification variation caused by changes in the thin-disk radius of curvature, are examined and the results prove that the designed eight passes optical system is optically and mechanically acceptable.