condenser aperture stop

An adjustable aperture stop located at the condenser aperture that controls its diameter, varying the numerical aperture and depth of field of illumination.

Synonyms: condenser aperture diaphragm

See also: condenser, condenser aperture, aperture stop, illuminating aperture

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The Microscope Optical Train

The optical train consists of an illuminator, condenser, specimen, objective, and detector.