In the displacement measurement system of scattering surface laser Doppler effect, the measuring accuracy is affected by the weakly Doppler signal that may be lost or discontinuous.
It is a simple principle and higher measurement precision without complicated phase unwrapping and calibration procession, and can be used to measure the discontinuous and spatial isolation shape.
且原理简单，测量精度高，不需要复杂的相位展开和校准过程，特别适用于测量突变面形和空间离散面形。
3
The surfaces of diffraction optical element (DOE) are often deep and discontinuous, which lead to some difficulties for measurement of the 3-d surface topography of DOE.