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nanotimes Research Electron Microscopy //

Scientists Revolutionise Electron Microscope © Based on Material by University of Sheffield

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esearchers at the University of Sheffield have revolutionised the electron microscope by deve-

loping a new method which could create the high- est resolution images ever seen. The new method, called electron ptychography, dispenses with the lens and instead forms the image by reconstructing the scattered electron-waves after they have passed through the sample using computers.

Scientists involved in the scheme consider their fin- dings to be a “first step” in a “completely new epoch of electron imaging”. The process has no fundamen- tal experimental boundaries and it is thought it will transform sub-atomic scale transmission imaging.

Project leader Professor John Rodenburg, of the University of Sheffield‘s Department of Electronic and Electrical Engineering, said: “We‘ve shown we can improve upon the resolution limit of an electron lens by a factor of five. An extension of the same me- thod should reach the highest resolution transmission image ever obtained; about one tenth of an atomic diameter. No longer does TEM have to be bound by the paradigm of the lens, its Achilles‘ heel since its invention in 1933.”

The new method also disposes of the need to put a lens very close to a living sample, meaning that cells can be seen through thick containers like petri dishes or flasks. This means that as they develop and

Top: Specimens can be viewed in containers instead of slides. Bottom: Plant cells seen without dying. © Faculty of Engineering at the University of Sheffield

12-02 :: February/March 2012