March 29, 1950 (on GY February 12), the Radio Corporation of America made a three-color television picture tubes.

1950 March 29, 2010, the Radio Corporation of America successfully demonstrated a fully electronic color television picture tubes. David Sarnoff, Chairman of the company announced that "We have embarked on the TV the threshold of a new era - the era of color television". (History com)
Radio Corporation of America actually exhibited two color CRT. One using a single branch electron gun, while the other uses only the three electron guns to produce a color image. Same two picture tube specifications with existing black and white TV. (L $ dj��.����T)
Radio Corporation of America is working with color images using the mechanical scanning disk CBS competition. Kinescope of the Radio Corporation of America, the advantage is that it is consistent with the existing black-and-white television transmission equipment, so that the audience can use their home television sets. Columbia TV system is not.