Like all complex devices, the television had many contributing inventors.
During the 1870s there were several people who worked on photo-electric devices that converted light into an electrical signal.
1876 was the year that Nipkow patented a rotating disc that could be used to capture and display an image using electricity. Although he had the patent, he never developed a useful working system with the disc and the patent expired some twenty years later.
John Logie Baird, a Scot living in England is recognized as the first to demonstrate an operational television in March of 1925. It was a public demonstration held in Selfridges, a London department store. His "Televisor" system showed moving images being delivered via an electrical signal. The system used the Nipkow disc to produce the images so Baird's work was based on research carried out many years before. Despite the use of the disc, Baird was the first to successfully produce an operational television.
The BBC began public television broadcasts in January 1929 using Baird's system from their London television studio. These continued for seven years until they moved to a new fully electronic system in 1936.
Meanwhile, Philo Farnsworth was working on similar ideas in America and in 1927, he also demonstrated an electro-mechanical television system. Just two years later in 1929, he demonstrated a fully electronic system with no moving parts. This was an important development as there were significant limitations with the electro-mechanical systems. Farnsworth's electronic system provided a means to increase resolution far beyond that of the Nipkow method.
Vladimir Zworykin, a Russian American filed a patent application in 1923 for the "iconscope", the first electronic camera tube. The patent was eventually granted in 1933. Zworykin worked with RCA during the 1930s and it was RCA who began the first commercial broadcasts of television in the US in 1939. His Iconscope tube was used for the first few years of broadcasting until it was replaced by more sensitive and higher resolution tubes during the 1940s.
The advent of color
As soon as black and white television was shown to the world, color television became the goal. Baird, supported by his successful demonstration of television in 1925 began work on the color version and gave a demonstration in 1928 of full color television. It was based on the electro-mechanical system used by his Televisor and never went into commercial production. Nonetheless, ot proved the concept of using red, green and blue signals to capture, deliver and display color television signals. Those principles are still in use today.
More than a decade later, Baird demonstrated a fully electronic color system that offered a 600 line resolution. The system once again proved concepts of signal handling and processing that were used for the later successful launch of commercial color services.
Later yearsBy the 1940s, television had become big business and the days of the independent inventor had passed. Future developments of color television were carried out by corporations and standards committees with the great inventors of the 1920s pushed to one side. It should be mentioned that despite the great improvements in quality and resolution of television, even now, television uses many of the principles developed by the great inventors, Baird, Farnsworth and Zworykin along with contributions from many others of the early 20th century.
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