Numerical aperture Sentence Examples
The function n sin u = A, for the microscope, has been called by Abbe the numerical aperture.
On the other hand, in immersion-systems the numerical aperture can almost amount to the refractive index, for A=n sin u
From the Fraunhofer formula I =X/n sin a one can immediately deduce the limit to the diffraction constant I, so that the banding by an objective of fixed numerical aperture can be perceived.
The value n sin u equals the numerical aperture A, where n is the refractive index of the immersion-liquid, and u is the semi-aperture on the object-side.
If microscopic preparations are observed by diffused daylight or by the more or less white light of the usual artificial sources, then an objective of fixed numerical aperture will only represent details of a definite fineness.Advertisement
With the best immersion-system, having a numerical aperture of 1.6, details of the size o.
In this way a monochromat for glycerin of a numerical aperture 1.25 gives a relative numerical aperture of 2.50.
The resolving power of an objective depends on its numerical aperture.
The numerical aperture can be determined in two ways.
The sine of this angle is the numerical aperture for dry lenses.Advertisement
The angular or numerical aperture can then be read off.
If the numerical aperture be known the resolving power is easily found.
A very commonly used dry condenser has a numerical aperture (NA) of 0.9.