threshold increment (TI)
[5.9.11.4.3] A measure of disability glare expressed as the percentage increase in contrast required between an object and its background for the object to be seen equally well with a […]
veiling luminance
[5.9.11.4.4] See equivalent veiling luminance.
contrast sensitivity
[5.9.4.5] See luminance contrast sensitivity.
contrast threshold
[5.9.4.6] See brightness contrast threshold.
contrast
[5.9.4.4] (See luminance contrast.)
Weber’s fraction
[5.9.4.3] (See luminance contrast.)
foveal vision
[5.8.3.2] [See central (foveal) vision.]
vision
[5.12] [See central (foveal) vision; mesopic vision; peripheral vision; photopic vision; and/or scotopic vision.]
Troxler effect
[5.9.20] A fading of visual perception because of a stabilized retinal image. For example, the retinal blood vessels that lie in front of the retina are not normally seen, because […]
visual threshold in point vision
[5.11.2] The weakest illuminance at the eye that makes it possible to see a small source against a given background. The psychophysical definition is the point illuminance that gives 50 […]