pinhole

In confocal microscopy, one or more pinhole apertures are used in a field plane in the emission light path, helping to reject out-of-focus light. This improves optical sectioning, resulting in a sharper image with less blur.

See also: confocal, confocal microscopy, optical section

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Introductory Confocal Concepts

A discussion of point scanning and pinhole detection using photomultipliers.