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APEX Method and Real-Time Blind Deconvolution of Scanning Electron Microscope Imagery



Alfred S. Carasso, David S. Bright, Andras Vladar


Loss of resolution due to image blurring is a major concern in electron microscopy. The point spread function describing that blur is generally unknown. Wer discuss the use of a recently developed fast Fourier transform (FFT)-based direct (noniterative) blind deconvolution procedure, the APEX method, that can process 512 x 512 images in seconds of CPU time on current desktop platforms. The method is predicated on a restricted but significant class of shift-invariant blurs, consisting of finite convolution products of heavy-tailed Levy probability density functions. Such blurs considerably generalize Gaussian and Lorentzian point spread functions. The method is applied to a variety of original scanning electron microscopy (SEM) micrographs and is shown to be useful in enhancing and detecting fine detail not otherwise discernible. Quantitative sharpness analysis of ideal sample micrographs, shows that APEX processing can actually produce sharper imagery than is achievable with optimal microscope settings.
Optical Engineering
No. 10


APEX method, blind deconvolution, direct methods, image deblurring, Levy density functions, SECB methods, SEM images


Carasso, A. , Bright, D. and Vladar, A. (2002), APEX Method and Real-Time Blind Deconvolution of Scanning Electron Microscope Imagery, Optical Engineering (Accessed May 19, 2024)


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Created September 30, 2002, Updated October 12, 2021