Standard Observer

A hypothetical visual system defined as mathematical equations (Color Matching Functions) intended to represent the typical human.

The Standard Observer is used as a universal technical definition of the perceptual effects of light stimuli on humans, specifically as part of the CIE 1931 Color Model.

While they may look like the Absorption Spectra of the cones, they are not intended to match, as the L-Cone does not have 2 peaks in its Absorption Spectrum like the ‘x’ Color Matching Function. In fact, the ‘x’ function is actually a mix of all 3 cones Absorption Spectra.

Absorption Spectrum of the Standard Observer. These three curves are the Color Matching Functions.