The defocusing fuzzy parameters of the point diffusion function obtained from high resolution wafer defocusing images are difficult to calculate and have low recovery efficiency.Therefore,a method of defocusing image restoration based on spot image is proposed.Firstly,the gray-scale projection of the spot image is carried out to obtain the line diffusion function curve.Then the line diffusion function curve is fit-ted and corrected to obtain the defocusing fuzzy parameters,so as to determine the point diffusion function.Finally,the second Wiener filter algorithm is used to restore the wafer defocusing image.The experimental results show that The second Wiener filter method proposed in this paper to estimate defocusing fuzzy pa-rameters for wafer defocusing images can significantly improve the peak signal-to-noise ratio(PSNR)of wafer defocusing images by at least 0.74 dB,reduce the blurring degree of wafer defocusing images,high-light the details of images,and reduce the calculation amount,thus improving the recovery efficiency.
关键词
晶圆离焦图像/离焦模糊参数/点扩散函数/二次维纳滤波
Key words
wafer defocusing image/defocusing fuzzy parameter/point spread function/secondary wiener filtering
维普
万方数据