How it began
Guillermo Gonzalez Camarena of Mexico City patented a chromoscopic adapter for television equipment in 1940, when he was 23 years old. The Mexican patent, number 40235, is dated August 19, 1940, and the original is kept by Mexico's Archivo General de la Nacion. He applied for a United States patent on August 14, 1941, and it was granted on September 15, 1942, as US patent 2,296,019.
Before it existed
Television cameras and receivers of the day worked in black and white. In his patent, Gonzalez Camarena described the invention as a simple and novel adapter for transmitting and receiving color images, one that could be fitted to existing equipment so that the black-and-white cameras of the time could capture color.
How it works
The adapter used a disk pierced with three holes holding glass filters for red, green and blue, labeled A, B and C in the patent drawings. One disk was placed in front of the camera and a larger one in front of the receiver screen. The disks turned on their axes so that the filters passed in front of the lens one after another. Each change of frame coincided with a change of color, and a synchronous motor kept the two disks in step.
What lasted
On January 21, 1963, the first color television transmission in the history of Mexican television was made on Channel 5, with the program Paraiso Infantil (Children's Paradise). The patent documents are now presented by the Archivo General de la Nacion as part of the country's documentary heritage.
