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The resolution or magnification of a microscope is limited by the wavelength of the viewing method. So light waves have a minimum wavelength of around 380nm ( x10-9m) but electrons have a de Broglie wavelength of around 12.2 x 10−12 m (12.2 pm) which allows for much higher resolution/magnification.

Its limitation in showing detail, due to a lower resolution capacity, which comes about as a result of differing sources of illumination. 

  • Size: Light microscopes are smaller and lighter, so are easier to move and set-up.
  • Cost / Availability: Light microscopes are less expensive than electron microscopes.
  • Radiation Type: Light microscopes use light (approx wavelength 400-700 nm), electron microscopes use beams of electrons (approx equivalent wavelength 1 nm).
  • Control of image formation : Light via glass lenses, beams of electrons can be focused using electromagnets due to negative charge on electrons.
  • Resolution*: Electron microscopes have much higher resolution than light microscopes
  • Magnification*: Electron microscopes have much higher magnification than light microscopes
  • 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). Electron microscopes produce greyscale (sometimes called "black and white") images. However, "false-colour" electron micrographs are common - and can be very beautiful!
  • Preparation of specimens : Generally involves harsher processes, e.g. using corrosive chemicals, for viewing via electron microscope than preparation of slides for viewing using a light microscope. 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)
  • Image Formation : Light microscope images can be viewed directly. Electron microscopes require use of a fluorescent screen, photographic plate or electronic display because electrons cannot be observed directly by the human eye.
  • 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.


Hi Mary, 

First of all, it may be helpful to consider light as particle-like "parcels" of energy called photons. When looking thorough a light microscope, in order to tell if two things are separate from each other (i.e. there is a gap between two things), then the photons must be able to fit through the gap. The better a microscope can tell two things apart, the better the "resolution". Now think about the difference between the size of photons (for a light a microscope) and the size of electrons (for an electron microscope). Which do think would be smaller (and therefore allow the microscope to have a better resolving power)?

Hope this helps

S  

Hi!

The main limitation of light microscopes are, that they have a lower resolution and cannot see beyond 200nm. And it cannot see smaller organelles like ribosomes. 

Limitations of electron microscopes:

It cannot observe living organisms as it is suppose to be placed in a vacuum, expensive, takes a huge amount of space and requires a great deal of skill to be able to operate an electron microscope.

:) Hope i helped 

This is a very popular question for AS level Biology! Suggest that you draw a table with three columns and three rows (3x3). Then use your course text book to complete the grid; a row for advantages for each,  and disadvantages.  Think about resolution, magnification, live versus dead specimen, degree of skill required to use the microscope, cost of equipment.  Hope this helps!

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