CRT COLORIMETRY .1. THEORY AND PRACTICE

The relationship was derived for computer-controlled color CRT display s between spectral radiant exitance emitted and digital counts. The de rivation was historical and could be traced to pioneering work in phot ographic sensitometry, vacuum tube physics, and broadcast television. By performing radiometric measurements relative to a display's maximum exitance, the model simplified to a two-stage model. The first stage was a nonlinear transformation relating normalized digital-to-analog c onverter values to device-dependent monitor tristimulus values using m odel parameters of gain, offset, and gamma. The second stage was a lin ear transformation where the device-dependent monitor tristimulus valu es were transformed to device-independent CIE tristimulus values. By u sing the model, colorimetric characterization accuracy of better than 0.5 CIELAB color-difference units for 125 colors sampling the display color gamut was achieved by measuring the CIE tristimulus values of on ly eight colors. The model had equivalent performance to methods using extensive measurements and table lookup. (C) 1993 John Wiley & Sons, Inc.