Signal-to-Noise Ratio in Confocal Microscopes

  • Colin J. R. Sheppard
  • Xiaosong Gan
  • Min Gu
  • Maitreyee Roy


Strictly, to obtain true confocal imaging the detector pinhole must be infinitesimally small, which would of course result in a vanishingly weak image signal. On the other hand, a very large pinhole degrades the confocal imaging effect. So in practice it is necessary to adopt some optimum diameter for the pinhole, which will depend on the design of the microscope, how it is operated, and the type of specimen. The resultant imaging performance then also depends on these various factors. In this way we can compare the performance of different designs of confocal microscope, and also compare them with widefield (WF) microscopes that have electronic image capture coupled with digital three-dimensional (3D) image restoration. In addition, we can understand how best to use the microscope in order to achieve optimum imaging performance.


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Copyright information

© Springer Science+Business Media, LLC 2006

Authors and Affiliations

  • Colin J. R. Sheppard
    • 1
  • Xiaosong Gan
    • 2
  • Min Gu
    • 2
  • Maitreyee Roy
    • 3
  1. 1.National University of SingaporeSingaporeSingapore
  2. 2.Swinburne UniversityMelbourneAustralia
  3. 3.University of SydneySydneyAustralia

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