Birefringence in the Cholesteric Unwinding Region

Birefringence in the Cholesteric Unwinding Region

Birefringent areas exhibit a wide spectrum of higher order colors in the unwinding region separating the true cholesteric from the high density phase. The image presented above illustrates the colors and textures observed in this region. The DNA concentration in this experiment is approximately 250 milligrams per milliliter, and the photomicrograph magnification is approximately 400x. Originally recorded on Fujichrome 64T transparency film using a Nikon Optiphot-Pol microscope with crossed polarized illumination, the image was digitized using a Nikon CoolScan transparency film scanner. Exposures were recorded about 3 f-steps under the recommended value given by an in-camera photomultiplier and were push-processed approximately 1.75 f-steps in the first E-6 developer.

© 1995-2013 by Michael W. Davidson and The Florida State University. All Rights Reserved. No images, graphics, software, scripts, or applets may be reproduced or used in any manner without permission from the copyright holders. Use of this website means you agree to all of the Legal Terms and Conditions set forth by the owners.
This website is maintained by our
Graphics & Web Programming Team
in collaboration with Optical Microscopy at the
National High Magnetic Field Laboratory.
Last modification: Thursday, Feb 26, 2004 at 10:29 AM
Access Count Since May 1, 2000: 19974