Are you remember of your first TV set in your house ? Try to remember how was long time ago when your TV was black-white. All family sit together at dinner table and watching his shiny friend - Television .Lot's of memory come on your mind I guess. And this is story about him ...
The development of the television occurred over a number of years, in many countries, and using a wide application of sciences, including electricity, mechanical engineering, electromagnetism, sound technology, and electro chemistry. No single person invented the television; instead, it is a compilation of inventions perfected by fierce competition.


        

Chemicals that are conductors of electricity were among the first discoveries leading to the TV. Baron Ons Berzelius of Sweden isolated selenium in 1817, and Louis May of Great Britain discovered, in 1873, that the element is a strong electrical conductor. Sir William Crookes invented the cathode ray tube in 1878, but these discoveries took many years to merge into the common ground of television.

Paul Nipkow of Germany made the first crude television in 1884. His mechanical system used a scanning disk with small holes to pick up image fragments and imprint them on a light-sensitive selenium tube. A receiver reassembled the picture. In 1888, W. Hallwachs applied photoelectric cells in cameras; cathode rays were demonstrated as devices for reassembling the image at the receiver by Boris Rosing of Russia and A. A. Campbell-Swinton of Great Britain, both working independently in 1907.

The first cathode ray tube scanning device was invented by the German scientist Karl Ferdinand Braun in 1897. Braun introduced a CRT with a fluorescent screen, known as the cathode ray oscilloscope. The screen would emit a visible light when struck by a beam of electrons. In 1907, the Russian scientist Boris Rosing used a CRT in the receiver of a television system that, at the camera end, made use of mirror-drum scanning. Rosing transmitted crude geometrical patterns onto the television screen and was the first inventor to do so using a CRT. The first practical signal generating tubes were invented by Vladimir K. Zworykin and Philo T. Farnsworth. Zworykin invented the iconoscope, which became the imaging iconoscope. Farnsworth invented the image dissector.
Countless radio pioneers including Thomas Edison invented methods of broadcasting television signals.



John Logie Baird of Scotland and Charles F. Jenkins of the United States constructed the first true television sets in the 1920s by combining Nipkow's mechanical scanning disk with vacuum-tube amplifiers and photoelectric cells. The 1920s were the critical decade in television development because a number of major corporations including General Electric (GE), the Radio Corporation of America (RCA), Westinghouse, and American Telephone & Telegraph (AT&T) began serious television research. By 1935, mechanical systems for transmitting black-and-white images were replaced completely by electronic methods that could generate hundreds of horizontal bands at 30 frames per second. Vladimir K. Zworykin, a Russian immigrant who first worked for Westinghouse then RCA, patented an electronic camera tube based on the cathode tube. Philo T. Farnsworth and Allen B. Dumont, both Americans, developed a pickup tube that became the home television receiver by 1939.

To the surprise of most people, television transmission began almost 25 years before the end of World War II. John Logie Baird, in England, and C. Francis Jenkins, in the United States, both made public demonstrations of television in 1925. Unlike post-war electronic televisions, these early systems used mechanical scanning methods.

Regular broadcast programming occurred in the United States, the United Kingdom, Germany, France, and the Soviet Union before World War II. The first regular electronic television broadcasts began in Germany in 1935, using first an electronic system with 180 lines, followed in 1937 with an improved system with 441 lines. The first regular public (i.e. not cable) television broadcasts with a modern level of definition (240 or more lines) were made in England in 1936 from Alexandra Palace.
Regular network broadcasting began in the United States in 1946, and television became common in American homes by the middle 1950s.


        

Shiny friend in color

Toshiba launched basic research on color televisions in 1950. As the USA chose the full electronic NTSC for their color television signal standard in December 1953, NHK Science & Technical Research Laboratory and the technical research divisions of TV manufacturers focused on research on the NTSC system.
From the late 1950s to the early 1960s, demand for monochrome television soared and created a new and thriving industry.
Commercial color television broadcasting began in September 1960, 7 years after monochrome broadcasting.

The Columbia Broadcasting System (CBS) had entered the color TV fray and battled with RCA to perfect color television, initially with mechanical methods until an all-electronic color system could be developed. Rival broadcasts appeared throughout the 1940s although progress was slowed by both World War II and the Korean War. The first CBS color broadcast on June 25, 1951, featured Ed Sullivan and other stars of the network. Commercial color television broadcasts were underway in the United States by 1954.

After overcoming production difficulties involving the three-color fluorescent screen and soldering of the frit seal glass, Toshiba completed a prototype of 17-inch square color picture tube on December 25, 1958. Two months later, on February 18, 1959, Toshiba completed the 430AB22 17-inch color picture tube using domestic parts developed by the trial production committee, and announced it as the first of its kind in Japan. Incorporating this picture tube, the 17-inch 17WG was launched in July 1960 as a genuine, made-in-Japan color television set.


        

Present and future of television

The future of television is now. High Definition Television (HDTV) was developed by the Japanese Broadcast Corporation and first demonstrated in 1982. This system produces a movie-quality picture by using a 1,125-line picture on a "letter-box" format screen with a 16 to nine width to height ratio. High-quality, flat screens suitable for HDTV are being perfected using synthetic diamond film to emit electrons in the first application of synthetic diamonds in electronic components.
Liquid crystal display (LCD) technology is also advancing rapidly as an alternative to the cumbersome television screen. Assorted computer chips add functions like channel labeling, time and data displays, swap and freeze motions, parental channel control, touch screens, and a range of channel-surfing options.

Flat panel (LCD or plasma)
Modern advances have brought flat panels to TV that use active matrix LCD or plasma display technology. Flat panel LCDs and plasma displays are as little as 25.4 mm (1 inch) thick and can be hung on a wall like a picture or put over a pedestal. Some models can also be used as computer monitors.

LED
technology has become one of the choices for outdoor video and stadium uses, since the advent of bright LEDs and driver circuits. LEDs enable scalable ultra-large flat panel video displays that other technologies may never be able to match in performance.

High Definition Television (HDTV)
In the early 2000s, a number of high-definition television standards were competing for the still-developing niche markets.Current HDTV standards are defined by the International Telecommunication Union (ITU-R BT.709) as 1080 active interlace or progressive scan lines, or 720 progressive scan lines, using a 16:9 aspect ratio. All current HDTV broadcasting standards are encompassed within the DVB specification.The term "high-definition" can refer to the resolution specifications themselves, or more loosely to media capable of similar sharpness, such as photographic film. As of 2007, 24 million US households have HDTVs.



        

Digital television of the future will allow the viewer to manipulate the angle of the camera, communicate with the sports commentator, and splice and edit movies on screen. Two-way TV will also be possible. Current screens may be used thanks to converter boxes that change the analog signal that presently energizes the phosphors on the back of your television screen to digital signals that are subject to less distortion—and are the language of computers. Computer technology will then allow a world of manipulation of the data as well as broadcast of six times as much data.