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A Spectrally Tunable LED Sphere Source Enables Accurate Calibration of Tristimulus Colorimeters



Irena Fryc, Steven W. Brown, Yoshihiro Ohno


The Four-Color Method (FCM) was developed to improve the accuracy of chromaticity measurements of various colors of a display. The method is valid for each type of display having similar spectra. To develop the Four-Color correction matrix, colorimeters measure the spectra of primary red, green, blue and white colors of a display. Consequently, a calibration facility should be equipped with number of different displays. This is very inconvenient and expensive.A Spectrally Tunable light Source (STS) that can mimic different display spectral distributions would eliminate the need for maintaining a wide variety of different displays and would enable a colorimeter to be calibrated for a number of different displays using the same setup. Simulations show that an STS that can create red, green, blue and white distributions that are close to the real SPD of a display works well with the FCM for the calibration of colorimeters.
Proceedings Title
Conference Lightmetry '04
Conference Dates
October 20-22, 2004
Conference Location
Warsaw, PL
Conference Title


color, colorimeter, dislay, Four Color Method, light emitting diode (LED), spectral power distribution


Fryc, I. , Brown, S. and Ohno, Y. (2004), A Spectrally Tunable LED Sphere Source Enables Accurate Calibration of Tristimulus Colorimeters, Conference Lightmetry '04, Warsaw, PL (Accessed April 12, 2024)
Created October 22, 2004, Updated June 13, 2017