Comparison of reference‐white standards for video display units

Abstract

There are two common chromaticity standards for video‐display‐unit reference white, one standard at 6500 K correlated color temperature (CCT), called D65 for short, and the other, an industrial standard, at 9300 K CCT. The choice of D65 evolved from the NTSC specification for television receivers based on Illuminant C—an average daylight at 6800 K CCT. Although originally the studio illumination was much redder than D65, modern television cameras operate in daylight, so a daylight white standard is most likely to allow exact color reproduction at the receiver. Hence average daylight is the most natural white point. However, many manufacturers chose 9300 K because the chromatic efficiency of the prevailing blue phosphors was greater than that of red or green phosphors, because viewers did not object to a blue color bias, and because 9300 K was bluer than any of the prevailing ambient illuminations. In the years since the adoption of the 9300‐K standard, these facts underwent some change, and also VDUs came to be used for graphics as well as for television. This paper outlines the reference‐white problem, and suggests a reevaluation of the 9300‐K standard.

Adaptation and colour matching of display and surface colours

“…A similar problem is noted by Brill (Personal Communication). 28 Fairchild describes a demonstration in which a piece of white paper illuminated by an incandescent lamp is compared with a colorimetrically identical white on the computer display 29 ; he notes that ''The CRT display will appear relatively high-chroma yellow''. In colour management it is commonly advised to calibrate the displays to a higher temperature white point than the illuminant in the viewing cabinet to achieve a better visual match.…”

Dynamic adaptation model and equal‐whiteness CCT curves for the choice of display reference white

“…The choice of D65 evolved from the NTSC specification for television receivers based on Illuminant C -an average daylight at 6774K CCT. 18 In this paper, we also propose the EWCCs for the choice of display reference-white by using the proposed DAM. The process of obtaining the EWCCs is shown in Fig.…”

“…In the U.S., color receivers are normally adjusted for a reference white point closer to 9300K + 27 MPCD (minimum perceptible color difference) because there has been a consumer preference for a very bluish white for TV. 18,21,22 The referencewhite of color video display units is selected at high CCT values by the TV manufacture, and this selected CCT value is quite different from the NTSC TV specification.…”