在冲击波过程中,利用成像型速度干涉仪探测样品自由面的速度时,散斑的叠加使得干涉曲线被严重干扰,影响了速度信息的精密提取。在理论上从光路的角度分析了系统中可能造成散斑的两种因素:靶面粗糙度和多模光纤。在实验上设计了三种照明方式分别对这两种因素进行验证。离线实验的结果表明,多模光纤的引入对散斑的产生起了主要的作用,这对抑制乃至遏制散斑的产生具有很好的指导性意义。 In the process of shock wave, using the imaging speed interferometer to detect the free surface velocity of the sample, the interference of the interference curve is severely disturbed by the superposition of the speckle, which affects the precise extraction of velocity information. In theory, two factors that may cause speckle in the system are analyzed from the perspective of optical path: the roughness of target surface and multimode optical fiber. In the experiment, three lighting methods were designed to verify these two factors respectively. The results of off-line experiments show that the introduction of multimode fiber plays a major role in speckle generation, which has a good guiding significance for the suppression and even the suppression of speckle generation.