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<title>Color characterization issues for TFTLCD displays</title>

2001; SPIE; Volume: 4663; Linguagem: Inglês

10.1117/12.452988

1996-756X

Gabriel G. Marcu, Wei Chen, Kok Chen, Peter Graffagnino, Olav Andrade,

Thin-Film Transistor Technologies

This paper describes few issues related to TFTLCD display color rendition and characterization. The paper points out specific aspects of color rendition on TFTLCD devices that differentiate the traditional CRT self luminous devices from the TFTLCD transmissive devices. Two TFTLCD technologies are discussed, TN (Twisted Nematic) and IPS (In Plane Switching) with and without dual domain improvement. The paper discusses specific aspects of color rendering for TN and IPS technologies, the display primaries, color gamut and brightness, the transfer function, the white point, some viewing angle issues and the color model. The paper explains why the TFTLCD displays offer perceptually a larger gamut than the CRT displays, even if chromatically their gamut triangle is smaller in the CIE chromaticity diagram than the one of a typical CRT. The paper also explains the hue shift effect of the primaries with the input voltage and the effect of luminance variation with the viewing angle, both encountered in some TN TFTLCD displays. The paper confirms that despite their advantages due to high brightness, high contrast, high sharpness, virtually no geometric image distortion, in terms of color capability, with few exceptions, TFTLCD devices have not yet surpassed the CRT devices with larger chromatic gamut and no color variation with the viewing angle.