Optics and Photonics Society of Iran

Abstract- In this paper, the design of a slab geometry based on a master oscillator power amplifier (MOPA) structure has been described. The slab geometry has been used for decreased of the thermal lensing effects that the output beam quality is increased. By using the Frantz-Nodvik equation of the amplifier energy in the slab geometry, the optimum output energy from amplified stages has been calculated. The fill factor in one of the important parameters of the energy amplification process, that in the parallel and perpendicular of the input surface are obtained for beam diameters of 5.18 and 5.73 mm respectively. Also the extracted energy from last stage 928 mJ was calculated. This calculations data have been good agreement with the experimental results.