In colorimetry, the OSA-UCS is a color space published in 1974 and developed by the Optical Society of America's Committee on Uniform Color Scales. Like the Munsell and Coloroid systems, it attempts to model perceptual color uniformity. OSA-UCS specifies colors by three coordinate values (L, j, g), which through equations can be derived from the CIE XYZ 1964 tristimulus values (X10, Y10, Z10).
References
MACADAM, David L.: Uniform color scales, Journal of the Optical Society of America (1974) 64(12):1691–1702.
MACADAM, David L.: Colorimetric data for samples of OSA uniform color scales, Journal of the Optical Society of America (1978) 68(1):121–130.
KOBAYASHI, Mitsuo; YOSHIKI, Kayoko: Effective conversion algorithm from OSA-UCS to CIEXYZ. Journal of the Color Science Association of Japan (2001) 25(2):193–203 [1]