Modern electron optics and the search for more light: The legacy of the muslim golden age

Abstract

Electron optics is the discipline of focussing a fine electron beam that could then scan the surface of solids in a wide range of applications. Electron microscopy, a major branch of electron optics, is a technique that has underpinned several significant scientific and technical advancements made over roughly the last 60 years. Its principal ability to resolve sub-atomic features continues to inspire scientists and engineers and enable new discoveries to be made. Whether in biology, medicine, physics, engineering, semiconductors, or material science, electron microscopy technology is a key ‘enabling tool’ that supports researchers to discover new phenomena and enhance our understanding. It is most likely to continue to play such a pivotal role for many decades to come. One area of applications that has enormously benefited from the use of this technique is the lighting industry. Light is vital to human life and developing light sources that come as close to natural light as possible is of prime importance. Electron microscopy continues to pave the way towards achieving this goal. The fundamentals of electron optics, particularly electron microscopy and parallels to optical microscopy, are briefly covered; but whilst electron opticians struggle to achieve the ultimate resolution in microscopy, their success is dependent on ‘image correction’- an imaging problem linked to a deficiency in the use of optical lenses first identified by the eleventh century Arab scientist Ibn al-Haytham. Examples showing the power of correcting for such deficiencies are presented in this chapter; alongside recent trends in electron microscopy which are also briefly reviewed.