Colorimetry is "the science and technology used to quantify and describe physically the human color perception." It is similar to spectrophotometry but is distinguished by its interest in reducing spectra to the physical correlates of color perception, most often the CIE 1931 XYZ color space tristimulus values and related quantities.
Colorimetric equipment is similar to that used in spectrophotometry. Some related equipment is also mentioned for completeness.
- A tristimulus colorimeter measures the tristimulus values of a color.
- A spectroradiometer measures the absolute spectral radiance (intensity) or irradiance of a light source.
- A spectrophotometer measures the spectral reflectance, transmittance, or relative irradiance of a color sample.
- A spectrocolorimeter is a spectrophotometer that can calculate tristimulus values.
- A densitometer measures the degree of light passing through or reflected by a subject.
- A color temperature meter measures the color temperature of an incident illuminant.