with which the standardization of instruments for color measurement could be finished. The apparatus system was based on LCD and was realized with FPGA. By recording and reproducing the calibration information
the white field apparatus could provide white field with standard color temperature. The FPGA controller board
the SVGA signal driver for LCD and NOR Flash ROM driver were designed and realized for the hardware and software system. As tested
the white field apparatus could provide standard white fields with adjustable color temperature after calibration by metrology institutes and operated steadily and reliably with the luminance error of 0.50% within 24 h.