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利用同步辐射光源，在Ｇａ和Ａｓ的Ｋ吸收限之间调节入射Ｘ射线的能量时，在对称劳厄情况下，ＧａＡｓ的（２００）衍射峰附近可观测到从ＧａＡｓ的入射面出射的Ｇａ的Ｋ系荧光Ｘ射线．当入射Ｘ射线的能量改变时，荧光曲线的非对称性会发生变化，变化趋势与相应的对称布喇格情况相类似．但是，劳厄情况下的变化不能解释为晶体内部Ｘ射线驻波的波节面相对于ＧａＡｓ（２００）格子面的移动．在劳厄情况下，Ｘ射线驻波的振幅随入射角的变化与结构因子的相位密切相关，因此结构因子的相位变化也会导致荧光曲线的非对称性变化．在假设原子的荧光溢出与该原子所在位置的电场强度成正比的基础上，给出了计算完整晶体在劳厄情况下荧光溢出的公式．该公式与实验结果符合得相当好
When using synchrotron radiation to adjust the incident X-ray energy between the K absorption limits of Ga and As, in the case of symmetric Laue, the Ga emitted from the GaAs incident surface can be observed in the vicinity of the (200) diffraction peak of GaAs K is a fluorescent X-ray. As the energy of the incident X-ray changes, the asymmetry of the fluorescence curve changes, and the change trend is similar to that of the corresponding symmetric Bragg case. However, the change in the Laue case can not be interpreted as the movement of the nodal plane of the X-ray standing wave relative to the lattice plane of GaAs (200). In the case of Laue, the amplitude of the X-ray standing wave is closely related to the phase of the structure factor with the change of incidence angle. Therefore, the phase change of the structure factor also causes the asymmetry of the fluorescence curve. Based on the assumption that the fluorescence spillover of atoms is proportional to the intensity of the electric field at the position of the atom, a formula for calculating the fluorescence spillover of a complete crystal under Laue conditions is given. The formula is in good agreement with the experimental results