In digital speckle interferometry, inhomogeneous illumination on or reflection from a tested object will lead to inhomogeneous fringe pattern, and even make the fringe missing.

• 在数字散斑干涉测量中,照明光的不均匀或被测试物反射光的不均匀,会导致条纹图像不均匀,严重时甚至会引起条纹的丢失。