A novel RGBW pixel for LED displays

In display technology, pixels are composed of three primary colors: red, green, and blue (RGB). Using the primary colors provides the ability to generate variety of hues including white. This concept is applied in light emitting diode (LED) displays where each pixel consists of RGB LEDs. Although using compact RGB light in LED displays provides a wide color gamut, many issues arise due to dissimilarities in optical and physical characteristics of LEDs such as: uniform spatial light mixing, distribution of achromatic point (AP), and thermal management. Power consumption is also a major concern in LED displays. In this paper, the issues with current RGB pixel architecture such as non-uniform mixing and distribution of AP, energy efficiency and a solution to these issues by introducing a new pixel configuration consisting of red, green, blue and white (RGBW) are discussed. Power measurements for an 8 × 8 pixel LED display has demonstrated up to 49% power savings for gray scale, over 30% power savings for low saturated colors, and up to 12% for high saturated colors using RGBW as an alternative. Experimental results as well as theoretical analysis of the new configuration are presented and discussed.