Dawes' limit

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diffraction pattern matching Dawes' limit

Dawes' limit is a formula to express the maximum resolving power of a microscope or telescope. It is so named after its discoverer, W. R. Dawes [1], although it is also credited to Lord Rayleigh.

The formula takes different forms depending on the units.

R = 4.56/D D in inches, R in arcseconds
R = 11.6/D D in centimeters, R in arcseconds
where D is the diameter of the main lens (aperture)
R is the resolving power of the instrument

See also[edit]

  1. ^ Dawes, W.R., Catalogue of Micrometrical Measurements of Double Stars. In: Memoirs of the Royal Astronomical Society, Vol. 35, p.137 1867, Bibcode1867MmRAS..35..137D