shows an observed SEM secondary electron image obtained from a specimen for astigmatism correction. The image restored by the accelerated RL is shown in Fig. 7(b) and that restored by the accelerated SRP in Fig. 7(c). The line profiles are taken at the same position as indicated by the line AB in Fig. 7(a). The beam intensity distribution in this experiment estimated with the electro-optical simulator under corresponding imaging condition was used as PSF. The image was reconstructed with five iterations for both algorithms. The image restored with the RL (Fig. 7(b)) has more improved edge sharpness than the observed image. In contrast, the image restored with the SRP (Fig. 7(c)) has additional improvements in sharpness and has excellent resolution , which can be especially seen in the dotted circles depicted in the line profile of Fig. 7(c). Note that the raised areas of the specimen, i.e., areas near the sharp edges, are generally much brighter than the flat areas in the SEM secondary electron images, which is called the edge effect. The edge effect can clearly be seen in the image restored with the SRP, while it is difficult to identify this in the observed image.