Calibration method for Correlated Color Temperature (CCT) measurement using RGB color sensors

The color is a feature derived from perceptual light that is reflected on objects, as such, represents a physical property. However, progress has been made in building mathematical models to define it more clearly. Light sources play an important role in the perception of colors and one of the measures to characterize their effect is the Correlated Color Temperature (CCT). The CCT is a measure used to characterize light sources representing the temperature of a black body in Kelvin to have the same chromaticity of the light source analyzed. In this work, we used a low-cost RGB sensor in order to find a model that can be transformed into XYZ space and then estimate the value CCT. Five groups of light sources were characterized using the values of the standard CIE color matching function. Later we found a transformation matrix to convert RGB into XYZ space, with this information the CCT was measured with an error value of less than 6%. This work is framed in the development of tools to control and lighting measurements in order to carry out control environments and characterization of artificial sources.