Real-Time Surface Topography Measurement with Graphic Processing Unit

White-light spectral scanning interferometry has been widely used in high precision surface topography measurement. However, existing data processing algorithms can hardly satisfy the requirement of real-time measurement due to the time-consuming calculations of a very large number of pixels in interferograms. We propose a parallel algorithm which implements graphic processing unit (GPU) to handle a series of pixels simultaneously in the real-time surface topography measurement. The surface topography measurement system based on white-light spectral scanning interferometry and the peak-counting algorithm is firstly introduced. Then, the programming agriculture based on Compute Unified Device Agriculture (CUDA) is briefly presented and the parallel algorithm to process the data using CUDA is discussed. Finally, an example is adopted to illustrate the precision and processing efficiency of the proposed method.