Television - Wikipedia, the free encyclopedia. This article is about television as a medium. For the appliance itself, see television set. It can refer to a television set, a television program (. Television is a mass medium, for entertainment, education, news, and advertising. Television became available in crude experimental forms in the late 1. After World War II, an improved form of black- and- white TV broadcasting became popular in the United States and Britain, and television sets became commonplace in homes, businesses, and institutions. During the 1. 95. The availability of storage media such as Betamax (1. VHS tape (1. 97. 6), DVDs (1. Blu- ray Discs (2. At the end of the first decade of the 2. Another development was the move from standard- definition television (SDTV) (5. HDTV), which provides a resolution that is substantially higher. HDTV may be transmitted in various formats: 1. Since 2. 01. 0, with the invention of smart television, Internet television has increased the availability of television programs and movies via the Internet through streaming video services such as Netflix, i. Player, Hulu, Roku and Chromecast. In 2. 01. 3, 7. 9% of the world's households owned a television set. Most TV sets sold in the 2. LEDs. Major manufacturers announced the discontinuation of CRT, DLP, plasma, and even fluorescent- backlit LCDs by the mid- 2. Alternatively television signals are distributed by coaxial cable or optical fiber, satellite systems and, since the 2. Internet. Until the early 2. A standard television set is composed of multiple internal electronic circuits, including a tuner for receiving and decoding broadcast signals. A visual display device which lacks a tuner is correctly called a video monitor rather than a television. Etymology. The word television comes from Ancient Greek . The first documented usage of the term dates back to 1. Russian scientist Constantin Perskyi used it in a paper that he presented in French at the 1st International Congress of Electricity, which ran from 1. August 1. 90. 0 during the International World Fair in Paris. The Anglicised version of the term is first attested in 1. The use of the term to mean . Includes programming schedule, membership information, and message board. Government, lifestyle, demographics, elected officials, education, social security, and other information from the State of Indiana. Earn your Penn State degree online. Penn State's World Campus offers accredited online college degrees and certificate programs. Learn more about our online. Member Benefits; Watch Shows On Your Schedule. Watch smart shows on your schedule with KPBS Passport, video streaming for members ($60 yearly), using your computer. Public broadcasting station for television, radio, and the internet. Includes program schedules and descriptions, education resources, and member information. This schematic shows the circular paths traced by the holes that may also be square for greater precision. The area of the disk outlined in black shows the region scanned. Facsimile transmission systems for still photographs pioneered methods of mechanical scanning of images in the early 1. Alexander Bain introduced the facsimile machine between 1. Frederick Bakewell demonstrated a working laboratory version in 1. As a 2. 3- year- old German university student, Paul Julius Gottlieb Nipkow proposed and patented the Nipkow disk in 1. Although he never built a working model of the system, variations of Nipkow's spinning- disk . Perskyi's paper reviewed the existing electromechanical technologies, mentioning the work of Nipkow and others. Fournier in Paris in 1. A matrix of 6. 4 selenium cells, individually wired to a mechanical commutator, served as an electronic retina. In the receiver, a type of Kerr cell modulated the light and a series of variously angled mirrors attached to the edge of a rotating disc scanned the modulated beam onto the display screen. A separate circuit regulated synchronization. The 8x. 8 pixel resolution in this proof- of- concept demonstration was just sufficient to clearly transmit individual letters of the alphabet. An updated image was transmitted . Moving images were not possible because, in the scanner: . On 2. 5 March 1. 92. Baird gave the first public demonstration of televised silhouette images in motion, at Selfridge's Department Store in London. By 2. 6 January 1. This is widely regarded as the first television demonstration. The subject was Baird's business partner Oliver Hutchinson. Baird's system used the Nipkow disk for both scanning the image and displaying it. A bright light shining through a spinning Nipkow disk set with lenses projected a bright spot of light which swept across the subject. A Selenium photoelectric tube detected the light reflected from the subject and converted it into a proportional electrical signal. This was transmitted by AM radio waves to a receiver unit, where the video signal was applied to a neon light behind a second Nipkow disk rotating synchronized with the first. The brightness of the neon lamp was varied in proportion to the brightness of each spot on the image. As each hole in the disk passed by, one scan line of the image was reproduced. Baird's disk had 3. In 1. 92. 7, Baird transmitted a signal over 4. London and Glasgow. In 1. 92. 8, 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. In 1. 92. 9, he became involved in the first experimental mechanical television service in Germany. In November of the same year, Baird and Bernard Natan of Path. In 1. 93. 1, he made the first outdoor remote broadcast, of the Epsom Derby. Baird's mechanical system reached a peak of 2. BBC television broadcasts in 1. Instead a 1. 7. 5mm film was shot, rapidly developed and then scanned while the film was still wet. An American inventor, Charles Francis Jenkins, also pioneered the television. He published an article on . In 1. 92. 5 Jenkins used the Nipkow disk and transmitted the silhouette image of a toy windmill in motion, over a distance of five miles, from a naval radio station in Maryland to his laboratory in Washington, D. C., using a lensed disk scanner with a 4. Transmitting Pictures over Wireless) on 3. June 1. 92. 5 (filed 1. March 1. 92. 2). Herbert E. Ives and Frank Gray of Bell Telephone Laboratories gave a dramatic demonstration of mechanical television on 7 April 1. Their reflected- light television system included both small and large viewing screens. The small receiver had a 2- inch- wide by 2. The large receiver had a screen 2. Both sets were capable of reproducing reasonably accurate, monochromatic, moving images. Along with the pictures, the sets received synchronized sound. The system transmitted images over two paths: first, a copper wire link from Washington to New York City, then a radio link from Whippany, New Jersey. Comparing the two transmission methods, viewers noted no difference in quality. Subjects of the telecast included Secretary of Commerce. Herbert Hoover. A flying- spot scanner beam illuminated these subjects. The scanner that produced the beam had a 5. The disc revolved at a rate of 1. It would be several years before any other system could even begin to compare with it in picture quality. It broadcast from the General Electric facility in Schenectady, NY. It was popularly known as . Meanwhile, in the Soviet Union, L. As part of his thesis, on 7 May 1. This prototype is still on display at the Takayanagi Memorial Museum in Shizuoka University, Hamamatsu Campus. His research in creating a production model was halted by the United States after Japan lost World War II. Nevertheless, the image quality of 3. UK broadcasts using the Baird system were remarkably clear. Two of these were the 1. Compagnie des Compteurs (CDC) installed in Paris in 1. Peck Television Corp. Mechanical television, despite its inferior image quality and generally smaller picture, would remain the primary television technology until the 1. The last mechanical television broadcasts ended in 1. United States. Electronic. In 1. 89. 7, English physicist. J. Thomson was able, in his three famous experiments, to deflect cathode rays, a fundamental function of the modern cathode ray tube (CRT). The earliest version of the CRT was invented by the German physicist Ferdinand Braun in 1. In 1. 90. 7, Russian scientist Boris Rosing used a CRT in the receiving end of an experimental video signal to form a picture. He managed to display simple geometric shapes onto the screen, which marked the first time that CRT technology was used for what is now known as television. They had attempted to generate an electrical signal by projecting an image onto a selenium- coated metal plate that was simultaneously scanned by a cathode ray beam. Although others had experimented with using a cathode ray tube as a receiver, the concept of using one as a transmitter was novel. Johnson (who gave his name to the term Johnson noise) and Harry Weiner Weinhart of Western Electric, and became a commercial product in 1. The device was first described in a patent application he filed in Hungary in March 1. Although his breakthrough would be incorporated into the design of RCA's . The patent for his receiving tube had been granted the previous October. Both patents had been purchased by RCA prior to their approval. Takayanagi did not apply for a patent. This is widely regarded as the first electronic television demonstration. While working for Westinghouse Electric in 1. But in a 1. 92. 5 demonstration, the image was dim, had low contrast, and poor definition, and was stationary. But RCA, which acquired the Westinghouse patent, asserted that the patent for Farnsworth's 1. Thus RCA, on the basis of Zworykin's 1. Farnsworth. Patent Office examiner disagreed in a 1. Farnsworth against Zworykin. Farnsworth claimed that Zworykin's 1. Zworykin received a patent in 1. In September 1. 93. RCA agreed to pay Farnsworth US$1 million over a ten- year period, in addition to license payments, to use his patents. Unfortunately, a problem with the multipactor was that it wore out at an unsatisfactory rate. However, Ardenne had not developed a camera tube, using the CRT instead as a flying- spot scanner to scan slides and film. His experiments with TV (known as telectroescop. On 2 November 1. 93. Emitron began at studios in 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. This was the world's first regular .
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