Year: 1926 10.02.
Venue: An attic in London, England
Baird invented TV without big gongs and drums. He only built a camera in his makeshift laboratory, which can scan the object with spotlight, convert the light and shadow of the scanned object into current with light tube, and project the original object onto the screen. Until 1926, 10 in June, he successfully scanned a puppet head, so he found a child named William Tynton as a toy. At that time, the screen color was pink (that is, black and white TV), and the picture was divided into 30 lines. The image flickered and the audience felt sick and headache after watching it.
The birth of color TV: 1953 color TV was officially listed in the United States. The first TV program was broadcast by ABC on April 30th, 1939. The content is President Roosevelt's opening speech at the new york World Expo.
The story of TV
television
Television is recognized by the world as one of the greatest inventions of the twentieth century.
history
Television was not invented by anyone. She is the crystallization of a large group of people in different historical periods and different countries. As early as the19th century, people began to discuss and explore ways to convert images into electronic signals. 1900 The word "TV" appeared.
People usually regard John Logie Baird, a scot, as a symbol of the birth of television by scanning the image of a puppet in an experiment in London from 1925 to 10.02. He is called "the father of television". However, this view is controversial. Because, also in that year, American vladimir zworykin showed his TV system to his boss in Westinghouse.
Although the time is the same, the TV systems in John Logie Baird and vladimir zworykin are quite different. Historically, John Logie Baird's television system was called mechanical television, while Sforokin's system was called electronic television. This difference is mainly due to the different transmission and reception principles.
The development of television is complicated. Almost at the same time, many people are doing the same research. In order to clarify history concisely.
We can divide the history of television into the following four parts:
Mechanical television
Electronic TV
colour television
Radio and television
For more details, please refer to the history of television.
at present
Now, television is undergoing a revolution.
Present situation of TV technology: One of the most obvious characteristics of TV technology is digitalization. The first is the digitization of program production. In the late 1990s, the British Broadcasting Corporation (BBC) took the lead in establishing the Columbus system in the world. The system makes the storage, editing and playing of BBC TV programs fully digital, that is, without tape, thus greatly improving the work efficiency of BBC and saving the production cost. In addition, the traditional analog cameras and video tapes are gradually being eliminated by the current television institutions, replaced by digital cameras and various emerging record carriers. This change has greatly improved the image quality. Secondly, the transmission technology is also diversified. In addition to the traditional wireless microwave transmission, there are now cable TV, satellite TV and other transmission methods. These new transmission modes effectively reduce the inevitable attenuation of signals during transmission and ensure better reception quality. Finally, the digital transformation of receiving technology (please see the next point: the status quo of TV sets). The improvement of sound quality and image quality and two-way interaction are the two biggest benefits brought by the wide popularization of digitalization.
The present situation of television. The TV set used by most people today is not much smaller than it was ten years ago. Because CRT technology is still the most commonly used display technology. The biggest disadvantage of this technology is that the size of the screen is proportional to the volume. And 34 inches is the maximum limit that this technology can reach. This obviously runs counter to people's needs. Therefore, more display technologies have emerged. Such as rear projection TV, LCD TV, plasma TV, etc. At the same time, with the digitalization of TV production and transmission technology, the digitalization of receiving equipment has become inevitable. Digital TV has better display effect and more functions, and can even realize preliminary two-way interaction. Another trend of TV is intelligence, that is, the combination with other electrical appliances, especially with computers. This will make TV more "intelligent" and more functional, thus breaking through the traditional meaning of TV (see "Prospect").
Television media. The rapid development makes people overwhelmed and more confused. Television media is seriously polarized. Well-known TV organizations, such as BBC and CNN, have a strong voice (see "Global Communication"). The degree of specialization is strengthened and the audience is narrower.
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