Application of differential weighting function to spatial filtering velocimetry

作者：He, Xin; Nie, Xiaoming; Zhou, Jian; Long, Xingwu^*

来源：Optik, 2015, 126(24): 5678-5681.

DOI：10.1016/j.ijleo.2015.08.159

• Low velocity measurement
• Differential weighting function
• Power spectral density
• Pedestal

The idea of applying differential weighting function of a spatial filter to spatial filtering velocimeter is put forward. The principle of this velocimeter is described on the basis of differential spatial filter constructed by a linear image sensor. The filtering characteristics of differential rectangular-type spatial filter with rectangular transmittance are theoretically analyzed by using a power spectral density function. This differential method is used to measure very low velocities of a conveyor belt driven by a high-precision rotary table. And it is also used in experiments of elimination of directional ambiguity by using frequency shifting. The theoretical and experimental results show that this differential-type velocimeter is suitable and practical for measuring very low speeds of solid surfaces. It is proved experimentally that the shifting frequency components result from the pedestal component, and both of them can be removed effectively by the method used.

• 出版日期2015
• 单位中国人民解放军国防科学技术大学