 |
 |
|
 |
 |
|
|
|
|
|
|
Encyclopedia :
N :
NU :
NUM :
Numerical aperture (microscopy) |
|
|
Numerical aperture (microscopy)In microscopy, the numerical aperture, AN, of an objective is:
where I is the index of refraction of the medium in which the lens is working (1.0 for air, up to 1.56 for oils), and a is the angular aperture of the lens. It is basically a measure of the diameter of the aperture compared to the focal length. In photography, the f-number expresses the same relationship.
|
|
|
This article is from Wikipedia. All text is available under the terms of the GNU Free Documentation License. |
|
| © 2008 Chamas Enterprises Inc. |
