Improving near field of high-power laser beams using two-photon absorption material

Experiments have been conducted on the pumping system of the SILEX-Ⅰ ultra-short pulse laser facility to study the optical power limiting property of a two-photon absorption material and the improvement of near field uniformity using the material. The output laser beam from a flashlamp-pumped Nd:YAG laser SAGA was used to measure the optical limiting property of the material. The results show that the optical power limiting property is obvious. The transmission rate of the material is very high and it is greater than 90% when the input intensity is less than 0.60 GW/cm2. Moreover online experiments done on the pumping system show that, modulation of near field spots is reduced greatly after the beam passes through the material and thus near field uniformity is improved.