Fundamental Limits in Confocal Microscopy

The previous chapter described how the confocal approach developed from conventional light microscopy and outlined the basic advantages gained by the use of confocal sampling techniques, primarily that the exclusion of light by the confocal pinhole makes it possible to record data from optical sections. This chapter will discuss the fundamental considerations that limit the performance of all confocal microscopes. Though at present no commercially available equipment approaches these limits, some simple tests will be described to help the user assess how well a given instrument performs. Additional information to help the user to operate the confocal microscope in an optimal manner can be found in Chapter 35, “ATutorial on Confocal Microscopy,” and Chapter 36, “Practical Confocal Microscopy.” These also include methods for measuring resolution and other useful parameters.