空间散斑的运动规律

相干光照明的漫射表面在空间中产生随机散斑。反射表面相对于光源运动,引起散斑的相应运动。当跟踪一个运动的斑,认为斑的强度不变,而位相是可以变化的。从Fresnel-Kirch-hoff积分,得到关于散斑运动的三个基本规则,即文中的(3),(4)和(5)式。第一和第二式类似于光栅方程。第三式类似于透镜定律。从这三个规则推导了当表面运动时散斑的运动公式(18)。这公式以矩阵形式表示,包括三个转动和三个平动。实验结果与公式非常符合。同时,三个基本规则适用于一般的空间衍射图。 关键词：

MOVEMENT OF SPACE SPECKLE

The diffusing reflective surface illuminated by coherent light generates random speckle in space. The movement of the surface relative to the source causes corresponding movement of the speckle. When a moving speckle is tracked, it implies that the intensity of speckle is constant yet the phase of the speckle is allowed to vary. From the Fresnel-Kirchhoff Integration, three fundamental rules of speckle movement are derived, i.e. Equations (3), (4) and (5) in this paper. The first and second equations are similar to those of grating. The third equation is similar to the lens law. From these rules, a speckle movement formula, relating to the surface movement, is derived as equation (18), in which the coordinate system adopted is fixed in space. It is an equation in matrix form, which denotes six types of surface movements, i. e. three rotations and three translations. The experimental results are in good agreement with this formula. These fundamental rules can be used to analyse general space diffractive patterns.