2. USES OF TRANSMISSION ELECTRON MICROSCOPE IN MICROSCOPY AND ITS ADVANTAGES AND DISADVANTAGES by O.P. CHOUDHARY, P.C. KALITA, P.J. DOLEY AND A. KALITA

Abstract

Transmission electron microscopy (TEM) is a microscopy technique in which a beam of electrons is transmitted through an ultra-thin specimen, interacting with the specimen as it passes through. An image is formed by the interaction of the electrons transmitted through the specimen; the image is magnified and focused onto an imaging device, such as a fluorescent screen or on a layer of photographic film, or to be detected by a sensor such as a CCD camera. TEMs are capable of imaging at a significantly higher resolution than light microscopes, owing to the small de Broglie wavelength of electrons. This enables the instrument's user to examine fine detail—even as small as a single column of atoms, which is thousands of times smaller than the smallest resolvable object in a light microscope. TEM forms a major analytical tool in physical as well as biological sciences. it finds application in cancer research, virology, materials science as well as pollution, nanotechnology, and semiconductor research etc.
KEY WORD: TEM, electrons, de Broglie wavelength, nanotechnology, CCD camera.