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History of television
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The history of television is both complex and far-reaching, involving the work of many inventors and engineers in several countries over many decades. Initially, work proceeded along two different but overlapping lines of development: those designs employing both mechanical and electronic principles, and those employing only electronic principles. Electromechanical television would eventually be abandoned in favor of fully electronic designs.
Electromechanical television
The origins of what would become today's television system can be traced back to the discovery of the photoconductivity of the element selenium by Willoughby Smith in 1873, the invention of a scanning disk by Paul Gottlieb Nipkow in 1884, John Logie Baird's demonstration of televised moving images in 1926 and Philo Farnsworth's Image dissector in 1927.
The 20 year old German university student Nipkow proposed and patented the first electromechanical television system in 1884, although he never built a working model of the system.
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Encyclopedia
The history of television is both complex and far-reaching, involving the work of many inventors and engineers in several countries over many decades. Initially, work proceeded along two different but overlapping lines of development: those designs employing both mechanical and electronic principles, and those employing only electronic principles. Electromechanical television would eventually be abandoned in favor of fully electronic designs.
Electromechanical television
The origins of what would become today's television system can be traced back to the discovery of the photoconductivity of the element selenium by Willoughby Smith in 1873, the invention of a scanning disk by Paul Gottlieb Nipkow in 1884, John Logie Baird's demonstration of televised moving images in 1926 and Philo Farnsworth's Image dissector in 1927.
The 20 year old German university student Nipkow proposed and patented the first electromechanical television system in 1884, although he never built a working model of the system. Nipkow's spinning disk design is credited with being the first television image rasterizer. Constantin Perskyi had coined the word television in a paper read to the International Electricity Congress at the International World Fair in Paris on August 25, 1900. Perskyi's paper reviewed the existing electromechanical technologies, mentioning the work of Nipkow and others. The photoconductivity of selenium and Nipkow's scanning disk were first joined for practical use in the electronic transmission of still pictures and photographs, and by the first decade of the 20th century halftone photographs, composed of equally spaced dots of varying size, were being transmitted by facsimile over telegraph and telephone lines as a newspaper service.
However, it wasn't until 1907 that developments in amplification tube technology, by Lee DeForest and Arthur Korn among others, made the design practical. The first demonstration of the instantaneous transmission of still silhouette images was by Georges Rignoux and A. Fournier in Paris in 1909, using a as the scanner, and a matrix of 64 selenium cells as the receiver.
In 1911, Boris Rosing and his student Vladimir Kosma Zworykin created a television system that used a mechanical mirror-drum scanner to transmit, in Zworykin's words, "very crude images" over wires to the electronic Braun tube (cathode ray tube or "CRT") in the receiver. Moving images were not possible because, in the scanner, "the sensitivity was not enough and the selenium cell was very laggy".
On March 25, 1925, Scottish inventor John Logie Baird gave a demonstration of televised silhouette images in motion at Selfridge's Department Store in London. AT&T's Bell Telephone Laboratories transmitted halftone still images of transparencies in May 1925. Charles Francis Jenkins was able to demonstrate on June 13, 1925, the transmission of the silhouette image of a toy windmill in motion from a naval radio station to his laboratory in Washington, using a lensed disk scanner with 48 lines per picture, 16 pictures per second.
However, if television is defined as the live transmission of moving images with continuous tonal variation, Baird first achieved this privately on October 2, 1925. But strictly speaking, Baird had not yet achieved moving images on October 2. His scanner worked at only five images per second, below the threshold required to give the illusion of motion, usually defined as at least 12 images per second. By January, he had improved the scan rate to 12.5 images per second. Then he gave the world's first public demonstration of a working television system to members of the Royal Institution and a newspaper reporter on January 26, 1926 at his laboratory in London. Unlike later electronic systems with several hundred lines of resolution, Baird's vertically scanned image, using a scanning disk embedded with a double spiral of lenses, had only 30 lines, just enough to reproduce a recognizable human face.
In 1927, Baird transmitted a signal over of telephone line between London and Glasgow. In 1928, Baird's company (Baird Television Development Company/Cinema Television) broadcast the first transatlantic television signal, between London and New York, and the first shore-to-ship transmission. He also demonstrated an electromechanical color, infrared (dubbed "Noctovision"), and stereoscopic television, using additional lenses, disks and filters. In parallel, Baird developed a video disk recording system dubbed "Phonovision"; a number of the Phonovision recordings, dating back to 1927, still exist. In 1929, he became involved in the first experimental electromechanical television service in Germany. In November 1929, Baird and Bernard Natan of Pathe established France's first television company, Télévision-Baird-Natan. In 1931, he made the first live transmission, of the Epsom Derby. In 1932, he demonstrated ultra-short wave television. Baird's electromechanical system reached a peak of 240 lines of resolution on BBC television broadcasts in 1936, before being discontinued in favor of a 405-line all-electronic system developed by Marconi-EMI.
In parallel, Herbert E. Ives of Bell Labs gave another dramatic demonstration of low-frame-rate television on April 7, 1927, when he field tested reflected-light television systems using small-scale (2 by 2.5 inches) and large-scale (24 by 30 inches) viewing screens over a wire link from Washington to New York City, and over-the-air broadcast from Whippany, New Jersey. The subjects, who included Secretary of Commerce Herbert Hoover, were illuminated by a flying-spot scanner beam that was scanned by a 50-aperture disk at a rate of 16 pictures per minute (about one picture every 4 seconds).
Meanwhile in Soviet Russia, Léon Theremin had been developing a mirror drum-based television, starting with 16 lines resolution in 1925, then 32 lines and eventually 64 using interlacing in 1926, and as part of his thesis on May 7, 1926 he electrically transmitted and then projected near-simultaneous moving images on a five foot square screen. By 1927 he achieved an image of 100 lines, a resolution that was not surpassed until 1931 by RCA, with 120 lines.
Electronic television
In 1911, engineer Alan Archibald Campbell-Swinton gave a speech in London, reported in The Times (UK), describing in great detail how distant electric vision could be achieved by using cathode ray tubes at both the transmitting and receiving ends. The speech, which expanded on a letter he wrote to the journal Nature in 1908, was the first iteration of the electronic television method that is still used today. Others had already experimented with using a cathode ray tube as a receiver, but the concept of using one as a transmitter was novel. By the late 1920s, when electromechanical television was still being introduced, inventors Philo Farnsworth, Vladimir Zworykin and Hungarian Kálmán Tihanyi were already working separately on versions of all-electronic transmitting tubes.
The decisive solution, the accumulation and storage of electrical charges ("photoelectrons") within the transmitting tube throughout each scanning cycle, was first described in 1926 by Kálmán Tihanyi, and appeared in a patent application for his "Radioskop" he filed in Hungary that same year. Tihanyi was awarded patents for his invention in both France and Great Britain in 1928, and applied for patents in the United States in June of the following year. Although this breakthrough would be incorporated into the design of RCA's "Iconoscope" in 1931, the U.S. patent for Tihanyi's transmitting tube would not be granted until May 1939. The patent for his receiving tube had been granted the previous October, and both would eventually be acquired by RCA.
On September 7, 1927, Philo Farnsworth's Image Dissector camera tube transmitted its first image, a simple straight line, at his laboratory at 202 Green Street in San Francisco. By 1928, Farnsworth had developed the system sufficiently to hold a demonstration for the press, televising a motion picture film. In 1929, the system was further improved by elimination of a motor generator, so that his television system now had no mechanical parts. That year, Farnsworth transmitted the first live human images with his system, including a three and a half-inch image of his wife Elma ("Pem") with her eyes closed (possibly due to the bright lighting required).
Farnsworth gave the world's first public demonstration of a complete all-electronic television system on August 25, 1934 at the Franklin Institute in Philadelphia. Other inventors had previously demonstrated components of such a system, or had shown an electronic system using still images or motion picture film. Manfred von Ardenne demonstrated an all-electronic television system using cathode ray tubes at the Berlin Radio Show in August 1931, but as he never built a camera tube, his system was limited to using the CRT as a flying spot scanner to transmit motion picture films and slides. Farnsworth became the first to use all-electronic cameras and receivers to transmit and receive live, moving images. Unfortunately, his cameras needed too much light, so his work came to a stop.
Vladimir Zworykin was also experimenting with the cathode ray tube to create and show images. While at Westinghouse in 1923, he developed an electronic camera tube. But in a 1925 demonstration, the image was dim, had low contrast and poor definition, and was stationary. The tube never got beyond the laboratory stage, but RCA (which had acquired the Westinghouse patent) believed the patent on Farnsworth's 1927 image dissector was written so broadly that it would exclude any other electronic formation of an image. And so RCA, armed with Zworykin's 1923 patent application, filed a patent interference suit against Farnsworth. The U.S. Patent Office examiner disagreed in a 1935 decision, finding priority of invention for Farnsworth against Zworykin. Farnsworth claimed that Zworykin's 1923 system would be unable to produce an electrical image of the type to challenge to Farnsworth's patent. Zworykin was unable or unwilling to introduce in evidence a working model of his tube that was based on his 1923 patent description. In October 1939, after losing an appeal in the courts and wishing to go forward with the commercial manufacturing of television equipment, RCA agreed to pay Farnsworth US$1 million (the equivalent of $13.8 million in 2006) over a ten-year period, in addition to license payments, to use Farnsworth's patents.
In 1931 RCA introduced an improved camera tube that relied on Tihanyi's principle of storage of electrical charges. Zworykin called the new tube the Iconoscope, and it would be the primary type of camera tube used in the U.S. until replaced by the image orthicon tube in 1946.
In Britain Isaac Shoenberg used Zworykin's design to develop Marconi-EMI's own Emitron tube, which formed the heart of the cameras they designed for the BBC. Using this, on November 2, 1936 a 405 line service was started from studios at Alexandra Palace, and transmitted from a specially-built mast atop one of the Victorian building's towers; it alternated for a short time with Baird's mechanical system in adjoining studios, but was more reliable and visibly superior. So began the world's first high-definition regular service. The mast is still in use today.
Also in 1936, according to Kálmán Tihanyi's daughter , Tihanyi described the principle of "plasma television" and designed the first flat panel receiver.
Color television
Broadcast television
Overview
Programming is broadcast by television stations, sometimes called "channels", as stations are licensed by their governments to broadcast only over assigned channels in the television band. At first, terrestrial broadcasting was the only way television could be widely distributed, and because bandwidth was limited, i.e., there were only a small number of channels available, government regulation was the norm.
In the U.S., the Federal Communications Commission (FCC) allowed stations to broadcast advertisements beginning 1941, but required public service programming commitments as a requirement for a license. By contrast, the United Kingdom chose a different route, imposing a television licence fee on owners of television reception equipment to fund the British Broadcasting Corporation (BBC), which had public service as part of its Royal Charter.
Practically every country in the world now has at least one broadcast television station. Television has grown up all over the world, enabling nearly every country to share aspects its culture and society with others.
United States and Canada
Below is a list showing when U.S. states and Canadian provinces established their first commercially licensed television stations.
United States
The first regularly scheduled television service in the United States began on July 2, 1928. The Federal Radio Commission authorized C.F. Jenkins to broadcast from experimental station W3XK in Wheaton, Maryland, a suburb of Washington, D.C. But for at least the first eighteen months, only silhouette images from motion picture film were broadcast.
Hugo Gernsback's New York City radio station began a regular, if limited, schedule of live television broadcasts on August 14, 1928, using 48-line images. Simultaneously, Gernsback published Television, the world's first magazine about the medium.
General Electric's experimental station in Schenectady, New York, on the air sporadically since January 13, 1928, was able to broadcast reflected-light, 48-line images via shortwave as far as Los Angeles, and by September was making four television broadcasts weekly. It is considered to be the direct predecessor of current television station WRGB.
General Broadcasting System's WGBS radio and W2XCR television aired their regular broadcasting debut in New York City on April 26, 1931, with a special demonstration set up in Aeolian Hall at Fifth Avenue and Fifty-fourth Street. Thousands waited to catch a glimpse of the Broadway stars who appeared on the six-inch (15 cm) square image, in an evening event to publicize a weekday programming schedule offering films and live entertainers during the four-hour daily broadcasts. Appearing were boxer Primo Carnera, actors Gertrude Lawrence, Louis Calhern and Lionel Atwill, WHN announcer Nils Granlund, the Forman Sisters, and a host of others.
CBS's New York City station W2XAB began broadcasting their first regular seven days a week television schedule on July 21, 1931, with a 60-line electromechanical system. The first broadcast included Mayor Jimmy Walker, the Boswell Sisters, Kate Smith, and George Gershwin. The service ended in February 1933. Don Lee Broadcasting's station W6XAO in Los Angeles went on the air in December 1931. Using the UHF spectrum, it broadcast a regular schedule of filmed images every day except Sundays and holidays for several years.
By 1935, low-definition electromechanical television broadcasting had ceased in the United States except for a handful of stations run by public universities that continued to 1939. The Federal Communications Commission saw television in the continual flux of development with no consistent technical standards, hence all such stations in the U.S. were granted only experimental and not commercial licenses, hampering television's economic development. Just as importantly, Philo Farnsworth's August 1934 demonstration of an all-electronic system at the Franklin Institute in Philadelphia pointed out the direction of television's future.
On June 15, 1936, Don Lee Broadcasting began a one month-long demonstration of high definition (240+ line) television in Los Angeles on W6XAO (later KTSL) with a 300-line image from motion picture film. By October, W6XAO was making daily television broadcasts of films. RCA and its subsidiary NBC demonstrated in New York City a 343-line electronic television broadcast, with live and film segments, to its licensees on July 7, 1936, and made its first public demonstration to the press on November 6. Irregularly scheduled broadcasts continued through 1937 and 1938. Regularly scheduled electronic broadcasts began in April 1938 in New York (to the second week of June, and resuming in August) and Los Angeles. NBC officially began regularly scheduled television broadcasts in New York on April 30, 1939 with a broadcast of the opening of the 1939 New York World's Fair. By June 1939, regularly scheduled 441-line electronic television broadcasts were available in New York City and Los Angeles, and by November on General Electric's station in Schenectady. From May through December 1939, the New York City NBC station (W2XBS) of General Electric broadcast twenty to fifty-eight hours of programming per month, Wednesday through Sunday of each week. The programming was 33% news, 29% drama, and 17% educational programming, with an estimated 2,000 receiving sets by the end of the year, and an estimated audience of five to eight thousand. A remote truck could cover outdoor events from up to away from the transmitter, which was located atop the Empire State Building. Coaxial cable was used to cover events at Madison Square Garden. The coverage area for reliable reception was a radius of 40 to from the Empire State Building, an area populated by more than 10,000,000 people (Lohr, 1940).
The FCC adopted NTSC television engineering standards on May 2, 1941, calling for 525 lines of vertical resolution, 30 frames per second with interlaced scanning, 60 fields per second, and sound carried by frequency modulation. Sets sold since 1939 which were built for slightly lower resolution could still be adjusted to receive the new standard. (Dunlap, p31). The FCC saw television ready for commercial licensing, and the first such licenses were issued to NBC and CBS owned stations in New York on July 1, 1941, followed by Philco's station WPTZ in Philadelphia. After the U.S. entry into World War II, the FCC reduced the required minimum air time for commercial television stations from 15 hours per week to 4 hours. Most TV stations suspended broadcasting. On the few that remained, programs included entertainment such as boxing and plays, events at Madison Square Garden, and illustrated war news as well as training for air raid wardens and first aid providers. In 1942, there were 5,000 sets in operation, but production of new TVs, radios, and other broadcasting equipment for civilian purposes was suspended from April 1942 to August 1945 (Dunlap).
Canada
The Canadian Broadcasting Corporation (CBC) adopted the American NTSC 525-line B/W 60 field per second system as its broadcast standard. It began television broadcasting in Canada in September 1952. The first broadcast was on September 6, 1952 from its Montreal, Quebec station CBFT. The premiere broadcast was bilingual, spoken in English and French. Two days later, on September 8, 1952, the Toronto, Ontario station CBLT went on the air. This became the English-speaking flagship station for the country, while CBFT became the French language flagship after a second English language station was licensed to CBC in Montreal later in the decade. The CBC’s first privately owned affiliate television station, CKSO in Sudbury, Ontario, launched in October 1953 (at the time, all private stations were expected to affiliate with the CBC, a condition that was relaxed in 1960–61 when CTV, Canada's second national English language network, was formed).
France
In November 1929, Bernard Natan established France's first television company, Télévision-Baird-Natan. On April 14, 1931, was the first transmission with a thirty-line standard by René Barthélemy. On December 6, 1931, Henri de France created the Compagnie Générale de Télévision (CGT). In December 1932, Bathélemy carried out an experimental program in black and white (definition: 60 lines) one hour per week, "Paris Télévision", which gradually became daily from early 1933.
The first official channel of French television appeared on February 13, 1935, date of the official inauguration of television in France which was broadcast in 60 lines from 8:15 to 8:30 pm. The program was of the actress Béatrice Bretty from the studio of Radio-PTT Vision at 103 rue de Grenelle in Paris. The broadcast had a range of 100 km (62 miles). On November 10, George Mandel, Minister of PTT, inaugurated the first broadcast in 180 lines from the transmitter of the Eiffel tower. On the 18th, Susy Wincker, first announcer since June, carried out a demonstration for the press from 5:30 to 7:30 pm. Broadcasts became regular from January 4, 1937 from 11:00 to 11:30 am and 8:00 to 8:30 pm during the week, and from 5:30 to 7:30 pm on Sundays. In July 1938, a decree defined for three years a standard of 455 lines VHF (whereas three standards are used for the experiments: 441 lines for Gramont, 450 lines for the Compagnie des Compteurs and 455 for Thomson). In 1939, there were about only 200 to 300 individual television sets, some of which were also available in a few public places.
With the entry of France into World War II the same year, broadcasts ceased and the transmitter of the Eiffel tower was sabotaged. On September 3, 1940, French television was seized by the German occupation forces. A technical agreement was signed by the Compagnie des Compteurs and Telefunken, and a financing agreement for the resuming of the service is signed by German Ministry of Post and Radiodiffusion Nationale (Vichy's radio). On May 7, 1943 at 3:00 evening broadcasts. The first broadcast of Fernsehsender Paris (Paris Télévision) was transmitted from rue Cognac-Jay. These regular broadcasts (5 1/4 hours a day) lasted until August 16, 1944. One thousand 441-line sets, most of which were installed in soldiers' hospitals, picked up the broadcasts.
In 1944, René Barthélemy developed an 819-line television standard. During the years of occupation, Barthélemy reached 1015 and even 1042 lines. On October 1, 1944, television service resumed after the liberation of Paris. The broadcasts were transmitted from the Cognacq-Jay studios. In October 1945, after repairs, the transmitter of the Eiffel Tower was back in service. On November 20, 1948, Mitterrand decreed a broadcast standard of 819 lines; broadcasting begins at the end of 1949 in this definition. France is the only European country to adopt it (others will choose 625 lines).
Germany
Electromechanical broadcasts began in Germany in 1929, but were without sound until 1934. Network electronic service started on March 22, 1935, on 180 lines using telecine transmission of film, intermediate film system, or cameras using the Nipkow Disk. Transmissions using cameras based on the iconoscope began on January 15, 1936. The Berlin Summer Olympic Games were televised, using both fully electronic iconoscope-based cameras and intermediate film cameras, to Berlin and Hamburg in August 1936. Twenty-eight public television rooms were opened for anybody who did not own a television set. The Germans had a 441-line system on the air in February 1937, and during World War II brought it to France, where they broadcast from the Eiffel Tower. The American Armed Forces Radio Network at the end of World War II, wishing to provide US TV programming to the occupation forces in Germany, used US TV receivers made to operate at 525 lines and 60 fields. US broadcast equipment was modified; they changed the vertical frequency to 50 Hz to avoid power line wiggles, changed the horizontal frequency from 15,750 Hz to 15,625 Hz a 0.5 microsecond change in the length of a line. With this signal, US TV receivers with only an adjustment to the vertical hold control had a 625 line, 50 field scan, which became the German standard.
United Kingdom
The first British television broadcast was made by Baird Television's electromechanical system over the BBC radio transmitter in September 1929. Baird provided a limited amount of programming five days a week by 1930. During this time, Southampton earned the distinction of broadcasting the first-ever live television interview, which featured Peggy O'Neil, an actress and singer from Buffalo, New York. On August 22, 1932, BBC launched its own regular service using Baird's 30-line electromechanical system, continuing until September 11, 1935. On November 2, 1936 the BBC began broadcasting a dual-system service, alternating between Marconi-EMI's 405-line standard and Baird's improved 240-line standard, from Alexandra Palace in London, making the BBC Television Service (now BBC One) the world's first regular high-definition television service. The government, on advice from a special advisory committee, decided that Marconi-EMI's electronic system gave the superior picture, and the Baird system was dropped in February 1937. TV broadcasts in London were on the air an average of four hours daily from 1936 to 1939. There were 12,000 to 15,000 receivers. Some sets in restaurants or bars might have 100 viewers for sport events (Dunlap, p56).The outbreak of the Second World War caused the BBC service to be suspended on September 1, 1939, resuming from Alexandra Palace on June 7, 1946.
The first transatlantic television signal was sent in 1928 from London to New York by the Baird Television Development Company/Cinema Television, although this signal was not broadcast to the public. The first live satellite signal to Britain from the United States was broadcast via the Telstar satellite on July 23, 1962.
The first live broadcast from the European continent was made on August 27, 1950.
Soviet Union (USSR)
The Soviet Union began offering 30-line electromechanical test broadcasts in Moscow on October 31, 1931, and a commercially manufactured television set in 1932. The first experimental transmissions of electronic television took place in Moscow on March 9, 1937, using equipment manufactured and installed by RCA. Regular broadcasting began on December 31, 1938.
Later development
The first regular television transmissions in Canada began in 1952 when the CBC put two stations on the air, one in Montreal, Quebec on September 6, and another in Toronto, Ontario two days later.
Technological innovations
The first live national television broadcast in the U.S. took place on September 4, 1951 when President Harry Truman's speech at the Japanese Peace Treaty Conference in San Francisco, California was transmitted over AT&T's transcontinental cable and microwave radio relay system to broadcast stations in local markets.
The first live coast-to-coast commercial television broadcast in the U.S. took place on November 18, 1951 during the premiere of CBS's See It Now, which showed a split-screen view of the Brooklyn Bridge in New York City and the Golden Gate Bridge in San Francisco. In 1958, the CBC completed the longest television network in the world, from Sydney, Nova Scotia to Victoria, British Columbia. Reportedly, the first continuous live broadcast of a "breaking" news story in the world was conducted by the CBC during the Springhill Mining Disaster, which began on October 23 of that year.
The development of cable and satellite television in the 1970s allowed for more channels and encouraged businessmen to target programming toward specific audiences. It also enabled the rise of subscription television channels, such as Home Box Office (HBO) and Showtime in the U.S., and Sky Television in the U.K.
Television sets
In television's electromechanical era, commercially made television sets were sold from 1928 to 1934 in the United Kingdom, United States, and Russia. The earliest commercially made sets sold by Baird in the UK in 1928 were radios with the addition of a television device consisting of a neon tube behind a mechanically spinning disk (the Nipkow disk) with a spiral of apertures that produced a red postage-stamp size image, enlarged to twice that size by a magnifying glass. The Baird "Televisor" was also available without the radio. The Televisor sold in 1930–1933 is considered the first mass-produced set, selling about a thousand units.
The first commercially made electronic television sets with cathode ray tubes were manufactured by Telefunken in Germany in 1934, followed by other makers in France (1936), Britain (1936), and America (1938). The cheapest of the pre-World War II factory-made American sets, a 1938 image-only model with a 3-inch (8 cm) screen, cost US$125, the equivalent of US$1,863 in 2007. The cheapest model with a 12-inch (30 cm) screen was $445 ($6,633).
An estimated 19,000 electronic television sets were manufactured in Britain, and about 1,600 in Germany, before World War II. About 7,000–8,000 electronic sets were made in the U.S. before the War Production Board halted manufacture in April 1942, production resuming in August 1945.
Television usage in the United States skyrocketed after World War II with the lifting of the manufacturing freeze, war-related technological advances, the gradual expansion of the television networks westward, the drop in set prices caused by mass production, increased leisure time, and additional disposable income. While only 0.5% of U.S. households had a television set in 1946, 55.7% had one in 1954, and 90% by 1962. In Britain, there were 15,000 television households in 1947, 1.4 million in 1952, and 15.1 million by 1968.
For many years different countries used different technical standards. France initially adopted the German 441-line standard but later upgraded to 819 lines, which gave the highest picture definition of any analogue TV system, approximately double the resolution of the British 405-line system. However this is not without a cost, in that the cameras need to produce four times the pixel rate (thus quadrupling the bandwidth), from pixels one-quarter the size, reducing the sensitivity by an equal amount. In practice the 819-line cameras never achieved anything like the resolution that could theoretically be transmitted by the 819 line system, and for color, France reverted to the same 625 lines as the European CCIR system.
Eventually most of Europe switched to the 625-line PAL standard, once more following Germany's example, with France adopting SECAM. Meanwhile in North America the original NTSC 525-line standard from 1941 was retained, although analog television broadcasting in the United States is scheduled to end on June 12 2009 in favor of digital-only broadcasting.
Television inventors/pioneers
Important people in the development of TV technology in the 19th or 20th centuries.
Television museums
See also
Further reading
- Abramson, Albert. The History of Television, 1880 to 1941. (1987). Jefferson, NC: McFarland & Co. ISBN 0-89950-284-9.
- Abramson, Albert. The History of Television, 1942 to 2000. (2003). Jefferson, NC: McFarland & Co. ISBN 0-78641-220-8.
- Burns, R. W. Television: An international history of the formative years. (1998). IEE History of Technology Series, 22. London: IEE. ISBN 0-85296-914-7.
- Fisher, David E. and Marshall Jon Fisher. Tube: the Invention of Television. (1996). Washington: Counterpoint. ISBN 1887178171.
- Shiers, George. Early Television: A Bibliographic Guide to 1940. (1997). Garland Reference Library of Social Science. ISBN 0-82407-782-2.
- Meyrowitz, Joshua(1985). No Sense of Place, Oxford University Press, New York.
External links
Links related to the development or history of television
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