光束相干引起的电致伸缩能驱动声子波，从而能加强受激布里渊散射（ＳＢＳ），提高相位共轭保真度稳定性。对折反池结构，采用２ｎｓ陡前沿的脉冲光泵浦，将双级钕玻璃放大器和ＳＢＳ池作为整体，测量了其相位共轭保真度。观测到输出激光的能量远场空间分布和相位共轭保真度稳定性在光束夹角θ５ｍｒａｄ时明显优于θ＞３０ｍｒａｄ。 Electrostriction caused by beam coherence can drive phonon waves, which can enhance SBS and improve stability of phase conjugate fidelity. The structure of the anti-fold-back pool is pumped by a pulsed light with a 2 ns steep front. The two-stage neodymium glass amplifier and the SBS pool are taken as a whole to measure the phase conjugation fidelity. It is observed that the far-field spatial energy distribution and phase conjugate fidelity stability of the output laser are better than θ> 30 mrad at the beam angle θ5 mrad.