reciprocal of the least perceptible luminance contrast, usually expressed as
Note 1 to entry: The value of
Note 2 to entry: The contrast sensitivity has unit one.
Note 3 to entry: This entry was numbered 845-02-48 in IEC 60050-845:1987.
Note 4 to entry: This entry was numbered 17-255 in CIE S 017:2011.