Hostname: page-component-78c5997874-8bhkd Total loading time: 0 Render date: 2024-11-09T15:58:15.875Z Has data issue: false hasContentIssue false

Universal Variable Brightfield–Darkfield Contrast: A Variant Technique for Improved Imaging of Problematic Specimens in Light Microscopy

Published online by Cambridge University Press:  23 May 2013

Timm Piper
Affiliation:
Laboratory for Applied Microscopy Research–Light Microscopy, Marienburgstr. 23, D-56859 Bullay, Germany
Jörg Piper*
Affiliation:
Clinic “Meduna”, Department for Internal Medicine, Clara Viebig Road No 4, D-56864 Bad Bertrich, Germany
*
*Corresponding author. E-mail: [email protected]
Get access

Abstract

Several problematic specimens, especially when composed of a complex three-dimensional architecture or very high or ultralow ranges in regional thickness and density, can be observed in improved clarity and precision when universal variable brightfield–darkfield contrast (UVBDC) is used. In this method, two different partial images are optically superimposed and interfere with each other, contributing to complementary visual information: a brightfield and a darkfield image. These images can be generated with concentric-peripheral, paraxial, or axial illuminating light. In all variants, variable transitions between bright- and darkfield are achievable. By use of a pancratic condenser (zoom system), the illuminating light can be universally adjusted and optimally adapted to each type of specimen and each type of objective (glass and mirror lenses). The concentric-peripheral variant is preferably carried out with normal glass lenses, the axial variant with mirror lenses. Glass lenses can also be used for UVBDC based on axial or paraxial light when combined with a special contrast tube, which is described in detail. Which technical variant of UVBDC might lead to the best result may be determined by the particular properties of the specimen, but all techniques described promise significant improvements in image quality and visual information.

Type
Materials Applications
Copyright
Copyright © Microscopy Society of America 2013 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Carl Zeiss Jena Company (1965). Interphaco for transmitted light. Factory print No. 30-305-1, Jena, Germany. Google Scholar
Carl Zeiss Jena Company (1976). Amplival. Factory print No. 30-048d-1, Jena, Germany. Google Scholar
Determann, H. & Lepusch, F. (1981a). Calculation of resolution. In The Microscope and Its Applications, pp. 1315. Wetzlar, Germany: E. Leitz Wetzlar Company.Google Scholar
Determann, H. & Lepusch, F. (1981b). Darkfield microscopy, phase contrast microscopy, interference contrast microscopy. In The Microscope and Its Applications, pp. 1824. Wetzlar, Germany: E. Leitz Wetzlar Company.Google Scholar
Gehne, H. (1952). Mirror Objectives for Light Microscopes, pp. 453460. Mosbach/Baden, Germany: Physik Verlag (in German).Google Scholar
Horn, E. & Zantl, R. (2006). Phase-contrast-light microscopy of living cells cultured in small volumes. Microsc Anal 101, 1517 (European edition).Google Scholar
James, P. (2003). The Heine condenser (part 1)—Some thoughts concerning a very useful substage accessory. Available at: http://www.microscopy-uk.org.uk/mag/indexmag.html?http://www.microscopy-uk.org.uk/mag/artsep03/pjheine.html.Google Scholar
Jenoptik Jena Company (1967). Mirror objectives and mirror condensers for microscopic examinations in ultraviolet, visible and ultrared light spectra, technical description, Jena, Germany (in German). Google Scholar
E. Leitz Wetzlar Company (1970). Devices for phase contrast—Assembly with the Heine condenser. Factory print No. 513-5c, Wetzlar, Germany. Google Scholar
Piper, J. (2010). Mirror lenses in light microscopy—Theoretical considerations and practical implications. Microsc Res Tech 73(7), 681693.Google Scholar
Piper, T. & Piper, J. (2012). Variable bright-darkfield-contrast (VBDC)—A new illumination technique for improved visualizations of complex structured transparent specimens. Microsc Res Tech 75, 537554.Google Scholar