Colour television

Color television is a television transmission technology that includes information on the color of the picture, so the video image can be displayed in color on the television set. It is an improvement on the earliest television technology, monochrome or black and white television, in which the image is displayed in shades of grey (greyscale). Television broadcasting stations and networks in most parts of the world upgraded from black and white to color transmission in the 1960s and 1970s. The invention of color television standards is an important part of the history of television, and it is described in the technology of television article.

In its most basic form, a color broadcast can be created by broadcasting three monochrome images, one each in the three colors of red, green, and blue (RGB). When displayed together or in rapid succession, these images will blend together to produce a full color image as seen by the viewer. One of the great technical challenges of introducing color broadcast television was the desire to conserve bandwidth, potentially three times that of the existing black-and-white standards, and not use an excessive amount of radio spectrum. In the United States, after considerable research, the National Television Systems Committee approved an all-electronic system developed by RCA which encoded the color information separately from the brightness information and greatly reduced the resolution of the color information in order to conserve bandwidth. The brightness image remained compatible with existing black-and-white television sets at slightly reduced resolution, while color televisions could decode the extra information in the signal and produce a limited-resolution color display. The higher resolution black-and-white and lower resolution color images combine in the eye to produce a seemingly high-resolution color image. The NTSC standard represented a major technical achievement.

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