The XYL-VI Luminance Photoelectric Colorimeter changes the traditional structure thoroughly, employs the digital X(λ), Y(λ), Z(λ) sensors to replace the traditional analogue sensors, employs the digital signal measurement system to replace the traditional analogue measurement system. The instrument has no analogue unit, thus it is very simple to overcome the zero drift that is impossible to be avoided in traditional colorimeter. The digital sensor has a large dynamic range. Moreover, it possesses strong anti-interference ability and it has high accuracy. The XYL-VI Luminance Colorimeter contains internal RS232 computer interface. The calibration is done by software. It is suitable for monitoring and remote applications. The XYL-VI Luminance Colorimeter can be calibrated by XYL-VI Luminance Colorimeter software to sample the data and print out the results. It can also be corrected by other standard light sources to obtain very high measuring accuracy of x, y color coordinates and color temperature. It is a real-time measuring system and run under Windows2000/XP.