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In 1911, [[Boris Rosing]] and his student [[Vladimir Zworykin|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]]) in the receiver. Moving images were not possible because, in the scanner, "the sensitivity was not enough and the [[selenium]] cell was very laggy".
Until these people worked on (and invented) their mechanic inventions, a [[hungarian]] engineer [[Kálmán Tihanyi]]
On [[March 25]], [[1925]], [[Scotland|Scottish]] inventor [[John Logie Baird]] gave a demonstration of televised silhouette images in motion at [[Selfridges|Selfridge's]] Department Store in [[London]]. But if television is defined as the contemporaneous transmission of moving, monochromatic images with continuous tonal variation — not still, silhouette or halftone images — Baird first achieved this privately on [[October 2]], [[1925]].<ref>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.</ref> 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 [[image resolution|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. ▼
worked (between 1923-1925) on a very different, much moderner system: the fully electronic system (He invented the
first fully electronic screen the CRT, and the first fully electronic videocamera: "iconoscope" ) He publicated his
works and inventions in January of 1926.
Tihanyi's system became the worldwide standard.
http://portal.unesco.org/ci/en/ev.php-URL_ID=4813&URL_DO=DO_TOPIC&URL_SECTION=201.html
▲On [[March 25]], [[1925]], [[Scotland|Scottish]] inventor [[John Logie Baird]] gave a demonstration of (mechanic) televised silhouette images in motion at [[Selfridges|Selfridge's]] Department Store in [[London]]. But if television is defined as the contemporaneous transmission of moving, monochromatic images with continuous tonal variation — not still, silhouette or halftone images — Baird first achieved this privately on [[October 2]], [[1925]].<ref>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.</ref> 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 [[image resolution|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 {{convert|438|mi|km}} 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 [[Stereoscopy|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.<ref>[http://www.tvdawn.com/tvimage.htm Restoring Baird's TV Recordings]</ref> 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-[[John Logie Baird|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 [[EMI|Marconi-EMI]].
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