Polychromatic solid-state lamps versus tungsten radiator: hue changes of Munsell samples

Colour-perception differences under illumination by two quadrichromatic solid-state sources of light have been studied with respect to a tungsten radiator with the same correlated colour temperature (2600 K). A virtual RYgCB source (illuminant), which contains red, yellow-green, cyan and blue components with the line width typical of AlGaInP and AlInGaN light-emitting diodes (LEDs), was fully optimized for the highest value of the general colour-rendering index (CRI) (R a = 98.3). An implemented RAGB source (lamp) contained commercially available red, amber, green and blue LEDs (R a = 79.4). Colorimetric calculations in the Commission Internationale de l'Eclairage 1976 (u', υ') colour plane for 40 Munsell colour samples (value 6, chroma/6, hue increment 2.5) revealed the differences in hue discrimination and distortion for both sources in the yellow-green and blue-cyan ranges. These differences were not revealed by the standard analysis of the special CRIs and were lower for the RYgCB illuminant, which contained primary LEDs in the sensitive ranges. A psychophysical experiment on seven subjects was performed using the RAGB lamp stabilized against thermal and ageing drifts. Despite different colour-perception abilities of the subjects under investigation, the experiment confirmed the calculation results. Methods of obtaining composite white light with high subjective ratings are discussed, based on the obtained data.

[1]  Roy S. Berns,et al.  Development of the 1929 munsell book of color: A historical review , 1985 .

[2]  W. A. Thornton,et al.  Luminosity and color-rendering capability of white light. , 1971, Journal of the Optical Society of America.

[3]  Michael S. Shur,et al.  OPTIMIZATION OF WHITE ALL-SEMICONDUCTOR LAMP FOR SOLID-STATE LIGHTING APPLICATIONS , 2002 .

[4]  M. Shur,et al.  Introduction to Solid-State Lighting , 2002 .

[5]  Nadarajah Narendran,et al.  Refrigerated display case lighting with LEDs , 2002, SPIE Optics + Photonics.

[6]  Gunther Wyszecki,et al.  Color Science: Concepts and Methods, Quantitative Data and Formulae, 2nd Edition , 2000 .

[7]  Michael R. Krames,et al.  Green phosphor-converted LED , 2002, SPIE Optics + Photonics.

[8]  Patricia Rizzo,et al.  Color and brightness discrimination of white LEDs , 2002, SPIE Optics + Photonics.

[9]  Michael S. Shur,et al.  White Complementary Solid-State Lamp , 2004 .

[10]  M. Shur,et al.  Optimization of white polychromatic semiconductor lamps , 2002 .

[11]  Dorothy Nickerson,et al.  Munsell renotations for samples of OSA uniform color scales , 1978 .

[12]  Regina Mueller-Mach,et al.  White-light-emitting diodes for illumination , 2000, Photonics West - Optoelectronic Materials and Devices.

[13]  János Schanda.  The Concept of Colour Rendering Revisited , 2002, CGIV.

[14]  Nadarajah Narendran,et al.  Evaluating white LEDs for outdoor landscape lighting application , 2002, SPIE Optics + Photonics.

[15]  D. Nickerson.  Technical Note: 1963 CIE Interim Method of Measuring and Specifying Color Rendering of Light Sources , 1964 .

[16]  Michael S. Shur,et al.  Optimization of multichip white solid state lighting source with four or more LEDs , 2001, SPIE Optics + Photonics.

[17]  Lei Deng,et al.  Color rendering properties of LED light sources , 2002, SPIE Optics + Photonics.

[18]  D. B. Judd,et al.  Color in Business, Science, and Industry , 1953 .

[19]  Michael S. Shur,et al.  Quadrichromatic white solid state lamp with digital feedback , 2004, SPIE Optics + Photonics.