Light Microscope and Electron Microscope
Light Microscope
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Electron Microscope (EM)
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1
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Techniques are simple
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High level of technical skill needed
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2
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Specimen preparation normally takes a few minutes to
few hours
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Specimen preparation often takes several days
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3
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Live or dead specimens may be seen
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Only dead and dried specimens can be seen
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4
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Surface view of
the specimen is poor
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Good surface details (SEM) or internal details (TEM)
can be seen.
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5
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Light rays are used to illuminate the specimen.
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Electron beam produced by the cathode is used
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6
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Condenser, objective and eye piece lenses are made of
glass.
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All lenses are electromagnets.
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7
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Resolving power
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Light microscope has low resolving power i.e., below 0.25
μm to 0.30 μm.
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Electron microscope ha high resolving power i.e., about
250 times more than light microscope. Thus it can resolve down to 0.0001 μm.
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8
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Magnification
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It has a useful magnification of 500x to 1500x.
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EM has direct magnification as high as 160,000x and
photographic magnification is 1000,000x or more
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9
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Mechanism of image formation
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In light microscope the image formation depends upon of
light absorption in different zones of the objects.
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In electron microscope, it is due to electron scattering.
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10
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Image is seen by eyes through ocular lens. No screen is
needed.
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The image is received on zinc sulphate fluorescent
screen or photographic plate
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11
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No vacuum is needed
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EM operates at high vacuum
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12
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Cheap and negligible running cost
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Very costly and heavy running costs
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