Confocal microscopy

Confocal microscopy offers several advantages over conventional widefield optical microscopy, including the ability to control depth of field, elimination or reduction of background information away from the focal plane (that leads to image degradation), and the capability to collect serial optical sections from thick specimens. The basic key to the confocal approach is the use of spatial filter (pinhole) to eliminate out-of-focus light whose thickness exceeds the immediate plane of focus.
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