Electron microscopy guide


TEM alignment

STEM alignment

Wave interference


Diffractive imaginging


Picture of John

I graduated in physics from the University of Exeter in 1982; then did my PhD (1986) and PDRA (1986-88) in the University of Cambridge. My early research work on instrumentation development for scanning transmission electron microscopy (STEM), and the application of new techniques including coherent nanodiffraction and energy loss spectroscopy to the study of material structure. I was a Royal Society Research Fellow from 1988, based in the Cavendish Laboratory Cambridge, working on the phase problem as applied to super-resolution methods in electron microscopy, ptychography and advanced methods of electron spectroscopy.

Here's a picture of me using the VG STEM in about 1989:

John on the HB501 STEM

I spent 1996-9 setting up an early .com enterprise.

I held the Chair of Materials Analysis in the (then) Materials Research Institute (now MERI)of Sheffield Hallam University between 1999-2003, where I worked on PVD coatings, advanced lubricious coatings, glow discharge optical emission spectroscopy, sol-gel coatings and contrast mechanisms in environmental scanning electron microscopy (ESEM).

In July 2003 I moved to the Department of Electrical Engineering in the University of Sheffield. I'm currently working on phase-retrieval methods, principally Ptychography at electron, visible light and X-ray wavelengths. I am currently seconded part-time to a spin-out company I helped found called Phase Focus Ltd.