Dictionary » N » Numerical aperture

Numerical aperture

numerical aperture

For a lens the resolving power depends upon the wavelength of light being used and inversely upon the numerical aperture. The N.A. Is the product of the refractive index of the medium (1 for air, 1.5 for immersion oil) and the sine of the angle, i, the semi angle of the cone formed by joining objects to the perimeter of the lens. The larger the value of N.A., the better the resolving power of the lens, most objectives have their N.A. Value engraved on the barrel and this should be quoted when describing an optical system.

Please contribute to this project, if you have more information about this term feel free to edit this page

Results from our forum

Please help us I.D. this micro-organism

... like.. What equipment are you using? What is the magnification and numerical aperture on the objective you're using? Third, you say you found an organism living in a human. ...

See entire post
by jyaron
Sun Aug 09, 2009 5:10 pm
Forum: Microbiology
Topic: Please help us I.D. this micro-organism
Replies: 4
Views: 4514

The Fiber Disease

... response was examined in detail after dark-field condensers of high numerical aperture were developed, beginning in 1909 with work done by Karl Reichert and culminating ...

See entire post
by Skytroll
Fri Feb 10, 2006 5:57 am
Forum: Human Biology
Topic: The Fiber Disease
Replies: 7403
Views: 6245181

This page was last modified 21:16, 3 October 2005. This page has been accessed 3,941 times. 
What links here | Related changes | Permanent link