Television invented

The 1920s saw a number of important advances in television technology, as an electronic system of scanning and transmitting images proved far superior to the various mechanical systems of the previous decades. Scientists such as Philo Farnsworth and Vladimir Zworykin worked to develop practical devices using the electronic system, resulting in the successful transmission of clear images late in the decade.

Late in the nineteenth century, scientists theorized that light and images could be transmitted by electric wire over long distances, just as sound was transmitted over telephone wires. Based on the principle of “scanning,” the process of converting visual images into electrical pulses that could then be transmitted, German inventor Paul Nipkow patented a mechanical system in the 1880s that used a spinning disk with holes that would permit light to pass through and onto a photoelectric cell, which converted the light to electricity. Another German, Karl Braun, later invented the cathode-ray tube, which would eventually become a key component in television sets. Scientists worked to refine Nipkow’s mechanical system throughout the early twentieth century, and in 1907, the Russian scientist Boris Rosing patented a system that used a rotating scanner with mirrors to capture images and a cathode-ray tube to display them.

Mechanical Television

During the 1920s, a number of scientists labored to perfect Nipkow’s mechanical television transmission system. In 1925, the American inventor Charles Jenkins demonstrated a mechanical system that transmitted moving silhouettes and displayed them using a modified radio. That same year, Scottish inventor John Baird televised a human face for the first time, using a system based on a scanning disk and lenses. Herbert Ives, a scientist working for Bell Laboratories, the research and development laboratory of the American Telephone and Telegraph Company and Western Electric, transmitted moving images from Washington, D.C., to New York in 1927 using a mechanical system. These and other attempts to scan, transmit, and reassemble moving images using mechanical methods were engineering successes, but they failed to produce the clear images needed to make television a commercially viable technology rather than a novelty.

Electronic Television

One of the early pioneers of electronic television was Philo Farnsworth, a self-taught inventor from Utah. Having developed an affinity for repairing electrical equipment at an early age, Farnsworth soon became interested in radio and mechanical television technology. Early in the 1920s, the teenage Farnsworth surmised that a picture could be scanned electronically, one line at a time, just as the fields of his family’s farm were plowed in rows. This scanned image could then be transmitted to a receiver. Farnsworth explained his model of television, based on the manipulation of electrons rather than a rotating mechanical device, to a teacher who took notes and copied Farnsworth’s diagram illustrating the process. These records would prove vital to Farnsworth’s later efforts to protect his patents.

In 1926, Farnsworth began to build and test his invention after receiving financial backing from several investors. This electronic system, which did not include the moving disks or lenses of the mechanical systems, used a glass tube that Farnsworth called an “image dissector.” This tube, which contained photosensitive material, converted the light from an image into electrons. The electrical current flowed into a glass receiver, which displayed the image. Farnsworth successfully transmitted a clear image in September of 1927. Between 1927 and 1929, he successfully demonstrated this completely electronic television system to the press and public and filed a number of patents.

A Russian immigrant to the United States, Vladimir Zworykin, who had studied under Rosing, also sought to create an electronic television system during the 1920s. In 1923, while employed by Westinghouse, Zworykin applied for a patent for the iconoscope, a television camera tube that used electrons to transmit images. However, his attempts to create a working model were largely unsuccessful, and the patent would not be granted until late in the next decade. Zworykin was hired by the Radio Corporation of America (RCA) in 1929, where he became a vital contributor to the company’s development of television technology.

Impact

Television technology came under intense scrutiny in the 1930s, when RCA, under the leadership of David Sarnoff, challenged Farnsworth’s patents, claiming that Zworykin’s 1923 patent application granted him priority of invention and established him as the true inventor of the electronic television system. A prolonged period of legal action ensued. For a number of reasons, including the fact that a working model of the device described in 1923 was not constructed until significantly after the successful testing of Farnsworth’s model, the patent court ruled in favor of Farnsworth. Despite losing in court, RCA became a major force in the further development of television, displaying the latest television technology at the 1939 World’s Fair in New York. The Federal Communications Commission began licensing commercial television stations in 1941, and over the next decade, early television networks began stretching across the country.

Bibliography

Godfrey, Donald G. Philo T. Farnsworth: The Father of Television. Salt Lake City: University of Utah Press, 2001. A biography of Farnsworth focusing on his patents and work in television.

Magoun, Alexander B. Television: The Life Story of a Technology. Westport, Conn.: Greenwood Press, 2007. A history of the development of television technology from the late nineteenth to the early twenty-first century.

Schatzkin, Paul. The Boy Who Invented Television: A Story of Inspiration, Persistence and Quiet Passion. Silver Spring, Md.: TeamCom Books, 2002. An account of Farnsworth’s life from childhood, his work developing electronic television, and his struggles with financial backers.

Stashower, Daniel. The Boy Genius and the Mogul: The Untold Story of Television. New York: Broadway Books, 2002. A chronicle of the early lives of Farnsworth and Sarnoff and of the later legal battles between them regarding Farnsworth’s and RCA’s patents for electronic television.

Todorovic, Aleksandar Louis. Television Technology Demystified: A Non-Technical Guide. Burlington, Mass.: Focal Press, 2006. A technical history of the development of television.