Ronchigram (after Italian physicist Vasco Ronchi �roŋkiref>) is the convergent beam

diffraction pattern Diffraction is the deviation of waves from straight-line propagation without any change in their energy due to an obstacle or through an aperture. The diffracting object or aperture effectively becomes a secondary source of the propagating wav ...

of a known object with features comparable to the diffracting wavelength. In the case of electron Ronchigrams

amorphous In condensed matter physics and materials science, an amorphous solid (or non-crystalline solid) is a solid that lacks the long-range order that is a characteristic of a crystal. The terms "glass" and "glassy solid" are sometimes used synonymousl ...

materials are used. The structure of the Ronchigram encodes information about the aberration phase field across the objective aperture. As such, Ronchigrams have become increasingly important with the invention of aberration corrected

scanning transmission electron microscopy A scanning transmission electron microscope (STEM) is a type of transmission electron microscope (TEM). Pronunciation is tɛmor �sti:i:ɛm As with a conventional transmission electron microscope (CTEM), images are formed by electrons p ...

References

External links

ronchigram.com
Web simulator for generating Ronchigrams. Electron microscopy Microscopy {{CMP-stub