Aeskulap-Stab
Introduction
Principles of 
 Phase Contrast
Principles of 
 Relief Phase Contrast
Material and  
 Methods
Results
Further technical 
 Developements
Discussion
Summary
Links
Contact
References
Summary

The quality of the images produced by conventional phase contrast microscopy can be significantly improved when the usual annular masks in the phase-contrast condenser are excentrically aligned with the phase rings in the objectives or replaced by other elements with a small aperture for the transmitted light.. By this, the specimen is only illuminated from one defined direction by oblique light beams.

 Compared with conventional phase contrast, the following parameters are improved when relief phase contrast is used:

  - three-dimensionality / relief effects of 3D imaging

  - contrast

  - depth of focus

  - planarity of the images

  - contour sharpness (sometimes)

  - colour resolution and colour purity (sometimes)

   - lower halo artifacts (sometimes)

Several ways for the technical implementation of relief phase contrast exist; these are dependent or independent of the position of the condenser aperture diaphragm. Thus, the various parameters which are influenced by the  illuminating aperture can be adapted to the individual features of the specimen. In contrast to conventional phase contrast, objectives from different manufacturers can be used simultaneously, so that their compatibility is improved.
 

Copyright: Joerg Piper, Bad Bertrich, Germany, 2007


 

[Introduction]
[Principles of Phase Contrast]
[Principles of Relief Phase Contrast]
[Material and Methods]
[Results]
[Further technical developements]
[Discussion]
[Summary]
[Links]
[Contact]
[References]