In 1931, the first electron microscope was developed by the physicist Ernst Ruska and the electrical engineer Max Knoll. The electron microscope uses electron beam as a source of illumination and electromagnets as lenses. It is operated under vacuum condition and it has a higher magnification and resolving ability than the normal visible light microscopes. It is widely used to investigate ultrastructure of biological and inorganic specimens.

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Chapter 1.8, Problem 1MQ

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In 1931, the first electron microscope was developed by the physicist Ernst Ruska and the electrical engineer Max Knoll. The electron microscope uses electron beam as a source of illumination and electromagnets as lenses. It is operated under vacuum condition and it has a higher magnification and resolving ability than the normal visible light microscopes. It is widely used to investigate ultrastructure of biological and inorganic specimens.

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