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John Logie Baird

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John Logie Baird

Bust of John Logie Baird in Helensburgh
Born August 13 1888
Helensburgh, Argyll, Scotland
Died June 14 1946
Nationality Scottish
Work
Significant projects television

John Logie Baird ( August 13 1888 June 14 1946) was a Scottish engineer and inventor of the world's first working television system. Although Baird's electromechanical system was eventually displaced by purely electronic systems (such as those of Vladimir Zworykin and Philo Farnsworth), his early successes demonstrating working television broadcasts and his colour and cinema television work earn him a prominent place in television's invention.

Baird was born in Helensburgh, Argyll, Scotland. He was educated at Larchfield Academy (now part of Lomond School), Helensburgh; the Glasgow and West of Scotland Technical College (which later became the University of Strathclyde); and the University of Glasgow. His degree course was interrupted by World War I and he never returned to graduate.

Television experiments

Although the development of television was the result of work by many inventors, Baird is one of its foremost pioneers and made major advances in the field. He is generally credited with being the first person to produce a live, moving television image in halftones by reflected light. Baird achieved this, where other inventors had failed, by obtaining a better photoelectric cell and improving the signal conditioning from the photocell and the video amplifier.

In his first attempts to develop a working television system, Baird experimented with the Nipkow disk, and in February 1924 demonstrated to the Radio Times that a semi-mechanical analogue television system was possible by transmitting moving silhouette images, such as his fingers wiggling, in his London laboratory. Baird gave the first public demonstration of moving silhouette images by television at Selfridges department store in London in a three-week series of demonstrations beginning on March 25, 1925.

On October 2, 1925 Baird successfully transmitted in his laboratory the first television picture with halftones: the head of a ventriloquist's dummy nicknamed " Stooky Bill" in a 30-line vertically scanned image, at five pictures a second. Baird went downstairs and fetched an office worker, 20-year-old William Edward Taynton, to see what a human face would look like, and Taynton became the first person to be televised in full tonal range.

First public demonstrations

On January 26, 1926 Baird repeated the transmission for members of the Royal Institution and a reporter from The Times in his laboratory at 22 Frith Street in the Soho district of London. By this time he had improved the scan rate to 12.5 pictures a second. It was the world's first demonstration of a true television system, one that could broadcast live moving images with tone graduation.

He demonstrated the world's first colour transmission on July 3, 1928, using scanning discs at the transmitting and receiving ends with three spirals of apertures, each spiral with a filter of a different primary colour; and three light sources at the receiving end, with a commutator to alternate their illumination. That same year he also demonstrated stereoscopic television. In 1932, he was the first to demonstrate ultra-short wave transmission.

Broadcasting

In 1927, Baird transmitted a long-distance television signal over 438 miles of telephone line between London and Glasgow; Baird transmitted the world's first long-distance television pictures to the Central Hotel at Glasgow Central Station. He then set up the Baird Television Development Company Ltd, which in 1928 made the first transatlantic television transmission, from London to Hartsdale, New York, and the first television programme for the BBC. In November 1929, Baird and Bernard Natan established France's first television company, Télévision-Baird-Natan. He televised the first live transmission of the Epsom Derby in 1931. He demonstrated a theatre television system, with a screen two feet by five feet, in 1930 at the London Coliseum, Berlin, Paris, and Stockholm. By 1939 he had improved his theatre projection system to televise a boxing match on a screen 15 ft by 12 ft (4.6 m by 3.7 m).

From 1929 to 1932, the BBC transmitters were used to broadcast television programmes using the 30-line Baird system, and from 1932-35, the BBC also produced the programmes in their own studio at 16 Portland Place. In November 1936, the BBC began alternating Baird 240-line transmissions with EMI's electronic scanning system which had recently been improved to 405-lines after a merger with Marconi. The BBC ceased broadcasts with the Baird system in February 1937, due mostly to the immobility of the Baird system's cameras.

Baird's television systems were replaced by the electronic television system developed by the newly-formed company EMI- Marconi under Isaac Shoenberg, which had access to patents developed by Vladimir Zworykin and RCA. Similarly, Philo T. Farnsworth's electronic "Image Dissector" camera was available to Baird's company via a patent-sharing agreement. However, the Image Dissector camera was found to be lacking in light sensitivity, requiring excessive levels of illumination.

Baird made many contributions to the field of electronic television after mechanical systems had taken a back seat. In 1939, he showed colour television using a cathode ray tube in front of which revolved a disc fitted with colour filters, a method taken up by CBS and RCA in the United States. On August 16, 1944 he gave the world's first demonstration of a fully electronic colour television display. His 600-line colour system used triple interlacing, using six scans to build each picture. In 1943, the Hankey Committee was appointed to oversee the resumption of television broadcasts after the war. Baird persuaded them to make plans to adopt his proposed 1000-line Telechrome electronic colour system as the new post-war broadcast standard. The picture quality on this system would have been comparable to today's HDTV. The Hankey Committee's plan lost all momentum partly due to the challenges of post-war reconstruction. The monochrome 405-line standard remained in place until 1985 in some areas, and it was three decades until the introduction of the 625-line system in 1964 and ( PAL) colour in 1967.

Other inventions

Some of Baird's early inventions were not fully successful. In his twenties he tried to create diamonds by heating graphite and shorted out Glasgow's electricity supply. Not long afterwards Baird perfected a glass razor; it was completely rust-resistant, but it shattered. Inspired by pneumatic tires he had a go at pneumatic shoes, but his prototype contained semi-inflated balloons which burst. He also invented a thermal undersock (the Baird undersock), which was actually moderately successful. Baird suffered from cold feet, and after a number of trials, he found that an extra layer of cotton inside the sock provided warmth.

Baird's numerous other developments demonstrated his particular talent at invention. He was a visionary and began to dabble with electricity. In 1928, he developed an early video recording device, which he dubbed Phonovision. The system consisted of a Phonodisc, which was a 78rpm record that could play a 30-line video signal. His other developments were in fibre-optics, radio direction finding, infrared night viewing and radar. There is discussion about his exact contribution to the development of radar, for his wartime defence projects have never been officially acknowledged by the British government. According to Malcolm Baird, his son, what is known is that in 1926 Baird filed a patent for a device that formed images from reflected radio waves, a device remarkably similar to radar, and that he was in correspondence with the British government at the time. Much of the information regarding Baird's work in this area is just beginning to emerge.

He built what was to become the world's first working television set by purchasing an old hatbox and a pair of scissors, some darning needles, a few bicycle light lenses, a used tea chest, and a great deal of sealing wax and glue.

There is a working model of the Baird televisor in the London Science Museum.

Last years

From December 1944 until his death two years later, Baird lived at a house in Station Road, Bexhill-on-Sea, immediately north of the station itself. Baird died in Bexhill-on-Sea, Sussex, England on June 14, 1946 after a stroke in February of that year. The old house was demolished in 2007 and the new block of flats on the site will be called "Baird Court".

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