![]() See the table at the bottom of this page for the advantages and disadvantages of light vs electron microscopes. * Differences due to the shorter equivalent wavelength of electron beams compared with visible light. Usage Limitations : Living specimens cannot be viewed using electron microscopes because electron microscopes require there to be a vacuum in the tube - otherwise the electrons would be absorbed by air molecules.Electron microscopes require use of a fluorescent screen, photographic plate or electronic display because electrons cannot be observed directly by the human eye. Image Formation : Light microscope images can be viewed directly.Therefore more skill required - both to prepare specimens and to interpret EM images (due to "artefacts" in images, artefacts = features in images that are not present in the specimen but rather are due to the processes used to prepare the specimen and produce the image) using corrosive chemicals, for viewing via electron microscope than preparation of slides for viewing using a light microscope. Preparation of specimens : Generally involves harsher processes, e.g.However, "false-colour" electron micrographs are common - and can be very beautiful! Electron microscopes produce greyscale (sometimes called "black and white") images. Colour Images: Light microscopes form images including the range of wavelengths (colours) provided by the light source - but remember that the colours seen are often due to stains rather than the actual colours present in nature).Magnification*: Electron microscopes have much higher magnification than light microscopes.Resolution*: Electron microscopes have much higher resolution than light microscopes.Control of image formation : Light via glass lenses, beams of electrons can be focused using electromagnets due to negative charge on electrons.Radiation Type: Light microscopes use light (approx wavelength 400-700 nm), electron microscopes use beams of electrons (approx equivalent wavelength 1 nm).Cost / Availability: Light microscopes are less expensive than electron microscopes.Size: Light microscopes are smaller and lighter, so are easier to move and set-up.Specimens must be carefully prepared using techniques appropriate for both the equipment and the sample e.g. ![]() Used in study and research in biology and medical sciences (more about histology), material sciences e.g. ![]()
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