1923, Russian-American scientist Zworykin applied for the patent of photoelectric picture tube, TV transmitter and TV receiver. He adopted a comprehensive "electronic TV" transmitting and receiving system for the first time and became a pioneer of modern TV technology. With the application of electronic technology in television, television began to go out of the laboratory and enter public life. 1925, British scientists successfully developed TV sets. 1928, 3 1 radio stations in new york, USA conducted the first television broadcasting experiment in the world. Because CRT technology has not completely passed the test, the whole experiment only lasted for 30 minutes, and only a dozen TV sets were watched. This announced the emergence of TV art as a social undertaking and an epoch-making event in the history of TV development.
From 65438 to 0929, American scientist eves played 50 lines of color TV images between new york and Washington, and invented color TV. 1933, Zworykin successfully developed camera tubes and picture tubes for TV camera shooting. The process of making TV camera and imaging completely electronic has been completed, and so far, the modern TV system has basically taken shape. Today, the imaging principle and equipment of TV cameras and TV receivers are improved according to his invention.
(2) The development of British and American TV art: The textbook emphasizes that TV art made great progress in Britain and America in 1930s and 1940s. It is suggested that teachers should combine teaching materials and supplement information appropriately.
1936165438+1On October 2nd, the British Broadcasting Corporation (BBC) broadcast a large-scale song and dance program in Alexandria Palace, a suburb of London, and launched a two-hour TV broadcast for the first time. There are only over 200 televisions in London, but it marks the beginning of the world television industry. The coverage of the Berlin Olympic Games that year was a great appearance of young TV career. At that time, * * * used four cameras to shoot the game. One of the most striking is the all-electronic camera. This machine is huge. The lens with a focal length of1.6m weighs 45kg and is 2.2m long. It is called TV cannon. Since then, quite expensive televisions have become popular among upper-middle class families in Britain. 1937, when the company broadcast the coronation ceremony of King George V of England, there were 50,000 viewers in Britain watching TV. 1939 When the Second World War broke out, about 20,000 families in Britain had televisions.
On April 30th, 1939, ABC broadcasted the opening speech of President Roosevelt at the World Expo and the TV program of the mass parade led by Mayor new york through the transmitter at the top of the Empire State Building. Thousands of people crowded into department stores to queue up to watch the new scene. At the end of World War II, there were about 7,000 televisions in the United States. Germany, France, Italy and other countries started TV before World War II.
(3) Popularization and application of TV art: It is suggested that teachers should grasp the teaching materials from three aspects: conditions, time and performance of TV art popularization.
Connecting with the achievements of the third scientific and technological revolution and combining with the whole teaching materials in this section, this paper points out the conditions for the popularization of TV art: the progress of electronic technology, the great changes of society, the new spiritual needs of human beings and the drive of commercial profits. It is suggested that teachers make some supplements from three aspects: TV development, TV broadcasting and TV program production. For example, TV has experienced rapid development from black and white to color, from electron tube and transistor TV to integrated circuit TV. At present, TV is developing in the direction of intelligence, digitalization and multifunction. Television broadcasting is also transmitted from satellite to satellite live broadcast.
Performance: The textbook takes the United States and China as examples to illustrate. First, after World War II, the development of American TV industry surpassed that of Britain: from 1949 to 195 1, the number of TV sets jumped from 1 10,000 to more than 1 10,000, and there were 780 TV stations in the United States from190. At the same time, there are only 1.9 million TV sets in Britain, 30,000 in France, 20,000 in Canada and 4,000 in Japan. By the end of 1993, 98% American families had at least one TV set, of which 99% were color TV sets.
1958, the first black-and-white TV set in China was born in Tianjin. In the same year, the pilot began. At that time, there were only over 50 black and white TV sets in China. 197 1 year, there are 32 TV stations in China. At the beginning of the 20th century, the TV coverage rate in Chinese mainland was as high as 94%.
Types of TV
The types of TV are not only divided into black and white and color as before. At present, in shopping malls: plasma, LCD, flat CRT, ultra-flat CRT, ultra-thin CRT, digital HD CRT, CRT rear projection, DLP rear projection, LCOS rear projection, LCD rear projection TV ... just in principle, so many can be divided. How to choose? Let's divide them into several categories first.
According to the use effect and appearance, the above TVs can be roughly divided into four categories: flat-panel TVs (plasma, liquid crystal and some ultra-thin wall-mounted DLP rear projection) and CRT kinescope TVs (flat-panel CRT, ultra-flat CRT, ultra-thin CRT, etc.). ), rear projection TV (CRT rear projection, DLP rear projection, LCOS rear projection, LCD rear projection) and projection TV.
The main advantages of flat-panel TV are that it is quite thin, can be hung on the wall to watch, and the display screen can be made very large (at present, the plasma can reach more than 60 inches, and the LCD can reach more than 47 inches). But its disadvantage is that its viewing angle and reaction speed are limited to some extent, and its price is extremely expensive.
The main advantages of CRT TV (only digital high definition here) are excellent in all aspects (high brightness and contrast, large viewing angle, fast response and good color reproduction), but its screen is only about 34 inches at the largest, and it is very thick and bulky, and it also consumes a lot of power. But in comparison, the price is still very cheap.
Rear Projection (CRT rear projection, DLP rear projection, LCOS rear projection, LCD rear projection) Traditional CRT rear projection is not very popular, and the market has been taken away by digital rear projection (DLP rear projection, LCOS rear projection, LCD rear projection). DLP light display rear projection is popular at present, because it can be said to be a real digital TV, with good performance in all aspects, large screen and small volume (we have said its imaging principle many times, welcome to Xinbao. com to find the answer), and it is the most popular one at present. LCD rear projection is slightly inferior because of its high calorific value and short bulb life.
Projection TV is actually a civilian version of the projector we saw in the company meeting room. It is usually installed at home and can be used to watch movies.