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The technique of using microscopes to view objects that are otherwise too small to be easily seen by the naked eye.

What questions should have this tag?

  1. Questions related to principles of microscopy (not extending too much in the field of optics)
  2. Sample preparation for microscopy
  3. Technical queries regarding instrument settings
  4. Analysis of microscopic image data

Some basic definitions

  1. Magnification: Ratio of the size of the image and the actual size of the object
  2. Focus: Actual or imaginary point of convergence of the rays refracted through the lens
  3. Numerical Aperture: The ability of an optical system to gather light and resolve two closely spaced objects. Defined by: NA = n*sinθ [where n is the refractive index of light and θ is the half-angle of the light cone formed between the object and the lens]
  4. Excitation and Emission (with respect to fluorescence microscopy): The wavelength of light absorbed or emitted by the major fluorophore, respectively.
  5. Quantum yield: Ratio of number of photons absorbed and number of photons emitted by a fluorophore