光参量啁啾脉冲放大(OPCPA)非线性过程是个可逆过程，信号光增大到最大值时抽运光能量已几乎被耗尽，随即进入过饱和放大阶段，能量会由信号光和闲频光重新回到抽运光中。提出了利用这一过程实现啁啾脉冲频谱整形的一种新方法。通过数值模拟说明了这种啁啾脉冲频谱整形方法的原理。计算结果也表明了通过改变抽运光强、调节相位匹配角、改变抽运脉冲波形能实现对脉冲频谱整形结果的有效控制，甚至可以通过选择适当的抽运光和信号光的同步关系，使放大后输出信号光有一定的频移，这一点可以用来抑制钛宝石饱和放大引起的光谱红移。

The optical parametric chirped pulse amplification (OPCPA) is a reversible nonlinear course. When the signal reaches its peak density, the pump power has been almost depleted. After this point,the over-saturating OPCPA course begins and the energy from the signal and idler reverses to the pump. A new method of the chirped-pulse spectrum shaping is put forward in this paper based on the above course. The theory of the new spectrum shaping method is explained by simulation. Also by simulation it is shown that by varying the pump intensity or adjusting the phase matching angle or changing the pump waveform, the output of spectrum shaping can be effectively controlled; even when signal and pump pulses are under the proper synchronous conditions, a frequency shift occurs at amplified signal, and the spectrum red-shift induced by Ti:sapphire saturation amplification may be suppressed.