Multiple solution in maximum entropy deconvolution of high resolution electron microscope images

Exit wave reconstructions using through focus series of HREM images

“…This exit wave is much more suitable for quantitative structure analysis than a single HREM image (as for instance suggested by Hovmoller et al, 1992 andHuang et al, 1996 or even several HREM images taken at several focus values, because the exit wave combines all obtainable phase and amplitude information in a directly interpretable manner, whereas this phase and amplitude information is only partly present and furthermore scrambled in a single HREM image. Fig.…”

“…The tests showed that the overall maximum can be reached within five iterations. Huang et al (1996) used the maximum entropy method to determine the exact focus of a single HREM image, which was deconvoluted with the transfer function of the electron microscope used. They also obtained multiple solutions.…”

Restoring defect structures in 3C-SiC/Si (001) from spherical aberration-corrected high-resolution transmission electron microscope images by means of deconvolution processing

“…8). In fact, only one of the peaks corresponds to the true structure, while others are caused by the Fourier image effect (Cowley andMoodie, 1957b, 1960), or due to some fictitious structures that are reversed in contrast or isomorphic to the true structure (Huang et al, 1996). It is not difficult to find out the correct solution among the multiple solutions because the structure of 3C-SiC is known.…”

Maximum entropy image deconvolution applied to structure determination for crystal Nd1.85Ce0.15CuO4−δ

“…Such phenomenon is common in image deconvolution, especially for simple crystal structures with small unit cells. This was discussed in detail (Huang et al, 1996) by referring to the conception of Fourier image effect Moodie, 1957, 1960). The image deconvolution for Fig.…”

“…(4)), in most of previous works dealing with the image deconvolution (Han et al, 1986;Hu and Li, 1991;Hu et al, 1992;Huang et al, 1996), a threshold value of CTF, W thr (H) (empirically between 0.1 and 0.2), was setup to exclude those reflections which fall in the zero cross of CTF or its vicinity. Later a modification was made to include the reflections forming the deconvoluted image as more as possible (Yang and Li, 2000).…”