Color tolerance is usually used to represent the difference between the X, Y value calculate by photo color electrical detection system software and the standard light source. The smaller the value, the higher the accuracy.
The spectrum of the standard light source will change with the change of color temperature. With the different color temperatures, the standard spectrum is different (usually, the ordinary detect device will recognize the color temperature range of the measured LED light source automatically, and determine the corresponding CCT value of the standard light source), and the color tolerance is different. At the same temperature, the reference standard spectrum is consistent, but color coordinates X, Y are different, and the color tolerance is different.
Unit of color tolerance: SDCM. In the performance requirements of single capped fluorescent lamps according to GB-T17262-2002, the color tolerance of the general energy-saving lamps is less than 5SDCM. In GB24823-2009, general lighting requirements for LED modules specified that the color tolerance of LED module is required less than 7SDCM.