利用变分法得到了任意光脉冲传输的一般特性及高斯光脉冲压缩（或扩展）的必要条件。这说明在一定初始条件下时空非对称的光脉冲也可形成“光子弹”，在某些区域内，通过时空耦合作用，光束的空间会聚可以导至脉宽的压缩 The variational method is used to get the general characteristics of any optical pulse transmission and the necessary conditions for the compression (or expansion) of the Gaussian optical pulse. This shows that under some initial conditions, the light pulse with asymmetric spatiotemporal formation can also form a “photon bomb”. In some areas, the spatial convergence of the beam can lead to the compression of the pulse width through space-time coupling