Analysis of Improved Contrast from a Chirped Pulse Amplification Laser System by Increasing the Beam Size in the Stretcher
宽光束进入展宽器提高输出脉冲对比度分析

The impact of the stretcher on the contrast ratio of the out pulse is analyzed making use of the ray-tracing method, which is based on the contrast ratio model of chirped pulse.When the beam size in the stretcher is increased from 2 mm to 40 mm,the contrast of the output pulse approximately increase two magnitude.When the input pulse is Sech2,the contrast of the output pulse is better than what the input pulse is Gassian or Rectangular.