*EM structure: EM consist largely of (1)Acylindrical column (a) Cathode, tungsten wire filament, a source of electron (b) Electromagnet lens, 1000-250,000X magnification (c) Screen, photographic plate, or film 2)Vacuum system (3) Electronically control console prowerful suppler 104-105V The formation of an image in the TEM depends on the differential scattering of electron by parts of the specimen The later is proportional to the amount of matter present in that part, that is its mass thickness, which is a measure of the number of atoms per unit area and their atomic density*EM structure:EM consist largely of (1) A cylindrical column (a) Cathode, tungsten wire filament, a source of electron (b) Electromagnet lens, 1000-250,000 X magnification (c) Screen, photographic plate, or film (2) Vacuum system (3) Electronically control console prowerful suppler 104 -105V The formation of an image in the TEM depends on the differential scattering of electron by parts of the specimen. The later is proportional to the amount of matter present in that part, that is its mass thickness, which is a measure of the number of atoms per unit area and their atomic density