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The RGB color model is an additive color model in which red, green, and blue light are combined in various ways to create other colors. The very idea for the model itself and the abbreviation "RGB" come from the three primary colors in additive light models.
Primary colors are related to biological rather than physical concepts, based on the physiological response of the human eye to light. The human eye contains photoreceptor cells called cones which normally respond most to yellowish-green, green, and blue light ( wavelengths of 564 nm, 534nm, and 420nm respectively). The color yellow, for example, is perceived when the yellow-green receptor is stimulated slightly more than the green receptor, and the color red is perceived when the yellow-green receptor is stimulated significantly more than the green receptor.
Although the peak responsitivities of the cones do not occur at the red, green and blue wavelengths, those three colors are described as primary because they can be used relatively independently to stimulate the three kinds of cones.
To generate optimal color ranges for species other than humans, other primary colors would have to be used. For species with four different color receptors, such as many birds, one would use four primary colors; for species with just two kinds of receptors, such as most mammals, one would use two primaries.
One common application of the RGB color model is the display of colors on a cathode ray tube or liquid crystal display such as a television picture tube or a computer's monitor. Each pixel on the screen can be represented in the computer's memory as independent values for red, green and blue. These values are converted into intensities and sent to the cathode ray tube or LCD display. By using the appropriate combination of red, green and blue light intensities, the screen can reproduce many of the colors between its black level and whiteAlternate meanings: White (disambiguation White is a color (more accurately it contains all the colors of the spectrum and is sometimes described as an achromatic color— black is the absence of color) that has high brightness but zero hue. The impression point. Typical display hardware used for computer monitors in 20032003 is a common year starting on Wednesday (link will take you to calendar), and also: The International Year of Freshwater The European Disability Year Summary Perhaps the defining global event of the year 2003 was the Invasion of Iraq launched by the U uses a total of 24 bitThis article is about the unit of information, see Bit (disambiguation) for other meanings. A bit (abbreviated b is the most basic information unit used in computing and information theory. A single bit (short for b inary dig it is a zero or a one, or a ts of information for each pixel (commonly known as bits per pixel or bpp). This corresponds to 8 bits each for red, green, and blue, giving a range of 256 possible values, or intensities, for each color. With this system, approximately 16.7 million discrete colors can be reproduced.