Reflecting High Numerical Aperture Darkfield Condensers

This tutorial explores how the shape and size of the hollow cone of light emitted by a hypothetical reflecting darkfield condenser changes with numerical aperture.

To operate the tutorial, use the slider to adjust the size and numerical aperture of the light cone. The darkfield condenser is drawn to resemble a paraboloid-style condenser that would normally have a fixed numerical aperture determined by the geometry and proximity of the reflecting surfaces. For the purposes of this tutorial, we have modified the light path through the condenser to mimic changes in numerical aperture that do not correlate with the actual shape of the condenser. Therefore, the tutorial should not be perceived as a true relationship between light cone numerical aperture and condenser geometry.

Contributing Authors

Mortimer Abramowitz - Olympus America, Inc., Two Corporate Center Drive., Melville, New York, 11747.

Matthew J. Parry-Hill and Michael W. Davidson - National High Magnetic Field Laboratory, 1800 East Paul Dirac Dr., The Florida State University, Tallahassee, Florida, 32310.