red, green, blue, yellow (RGBY)
RGBY stands for Red, Green, Blue, Yellow and is an extended color model used in RGBY displays. Like RGBW, which adds a white subpixel, RGBY adds a yellow subpixel.
Each individual color pixel thus consists of four subpixels. In classic RGB displays, the coloryellow is produced by activating the green and red subpixels. However, the green-red combination does not produce pure yellow due to production constraints. Therefore, in RGBY, the yellow subpixel is activated separately and produces a strong yellow. As a result, the overall display has a larger color space and can represent more colors, especially since eye sensitivity is highest for green and yellow tones.