apostilb


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ap·o·stilb

(ap'ō-stilb),
A unit of brightness equal to 0.1 millilambert.
[G. apo, from + stilbē, lamp]

apostilb

An obsolete, non-SI (International System) unit of light, defined as the amount of light emitted from a diffusing surface corresponding to 1.0 lumen/m2.

apostilb 

The luminance of a perfectly diffusing surface that reflects 1 lumen per square metre. This measure is often used in visual field analysis, where the luminance of the background and targets is measured in apostilb.