电视 (Television 、TV）指使用电子技术传送活动的图像画面和音频信号的设备，即电视接收机，也是重要的广播和视频通信工具，最早由英国工程师约翰·洛吉·贝尔德在1925年发明。
Television (TV) refers to a device that uses electronic technology to transmit moving image pictures and audio signals, that is, a television receiver, which is also an important broadcast and video communication tool. It was first invented by British engineer John Logy Baird in 1925.
German electrical engineer Nipkov used his invented “Nipkov Disc” to use a mechanical scanning method to make the first experiment of transmitting images. Each picture has 24 lines, and the image is quite blurry.
Kemper Swinton in the United Kingdom and Rosenckoff in Russia put forward the principle of electronic scanning, which laid the theoretical foundation for television technology.
One of the inventors of television was the Soviet-American Zwarikin (also translated as Veratimir Sforodin) invented the electrostatic storage camera tube. In 1923, the electronic scanning picture tube was invented, which was the forerunner of television photography.
British John Rocky Baird, based on the “Nipkov Disc”, conducted new research work and invented a mechanical scanning TV camera and receiver. At that time, the resolution of the picture was only 30 lines, the scanner could only scan the scanning area 5 times per second, and the picture itself was only 2 inches high and one inch wide. Performed to the public in a small shop in London.
Baird, one of the inventors of television, gave a broadcast and reception performance to the British press.
Baird conducted the first electromechanical TV trial broadcast via telephone cable; the first shortwave TV trial; the British Broadcasting Corporation began to broadcast TV programs continuously for a long time.
Realize the simultaneous broadcasting of TV image and sound.
Put the film on the TV screen for the first time. People watched the live broadcast of the famous British local jockey club on television in London. American Ferro Farnsworth, one of the inventors of television, invented a tube television device that can project 25 images per second.
The British Broadcasting Corporation adopted Baird’s electromechanical TV broadcasting, and for the first time broadcasted TV images with high definition and entered the practical stage.
American Radio Corporation began to broadcast all-electronic television. Swiss Philip invented the first black and white TV projector.
U.S. Guerma developed an electromechanical color television system.
December 17, 1949
The first TV cable laid between London and Suden Calfelter was opened.
American H. Lowe invented a three-gun shadow mask color picture tube, and Lorenian invented a single-gun color picture tube.
Texas Instruments Corporation of the United States developed the first all-transistor television receiver.
American Radio Corporation developed integrated circuit televisions. Three years later, a color television receiver with an electronic tuning device was produced.
Japan developed a color TV projector.
Digital technology is used in TV broadcasting, and experiments prove that digital TV can be used in satellite communications.
The UK has completed the study of the “TV Library” system, and users can directly use the TV to check news, books, or magazines.
Britain developed the first batch of portable televisions.
The world’s first “cable TV” was launched in London. It was invented by the British Post Office. It can transmit the information in the computer through the ordinary telephone line and display it on the user’s TV screen.
Sony Corporation of Japan has developed a pocket black and white TV with a 2.5-inch LCD screen and battery-powered.
Panasonic Corporation of Japan launched “Universal TV”. The system’s picture is 3.6 meters wide and 4.62 meters high, which is equivalent to 210 inches. It can be placed on a small truck and played in small streets and squares where needed. The system uses the “high-brightness color luminous tube” exclusively developed by Panasonic, which can get colorful and bright images outdoors even in the daytime.
March 17, 1985
At the Tsukuba Science World Expo held in Japan, a color video wall with ultra-small screens built by Sony was unveiled. It is located on the central square, 40 meters long, 25 meters high, with an area of 1,000 square meters, and the entire building is as high as a 14-story building. It is quite a 1857-inch color TV. The ultra-small screen consists of 36 small luminous screens, each weighing 1 ton and 1.8 meters thick, with 4 lines and 9 works totaling 450,000 color luminous elements. Through the camera installed on the top, various activities on the venue can be displayed at any time, and various advertising videos of Sony can be played.
British Telecom (BT) launched an integrated digital communication network. It provides users with voice, fast transmission chart, fax, slow scan TV terminal and so on.
November 25, 1991
Japan’s Sony’s high-definition TV began trial broadcasting: its scanning lines were 1,125, and the image quality was improved by 100%; the aspect ratio of the screen was changed from the traditional 9:12 to 9:16, which enhanced the viewer’s sense of presence; Extending from 10 degrees to 30 degrees, the map has a more sense of depth; the number of “pixels” on the TV’s surface image has increased from 280,000 to 1.27 million. The amount of information per unit area has increased by nearly 4 times… Therefore, watch high-definition The distance of the TV is not 7 times of the previous screen height but 3 times, and the accompanying sound is lifelike, using 4-channel high-fidelity stereo, which is full of appeal.
the year 1995
Japan’s Sony Corporation has launched an ultra-miniature color TV receiver (ie, palm-type color TV), which is as small as a palm and weighs 280 grams. It has a speaker and a headphone jack. The LCD screen is about 5.5 cm. The picture looks small, but the image is clear. Its most obvious feature is: the human body is used as an antenna to achieve the viewing effect, and the two leads are used when watching TV. Put it around your neck to get the effect of an outdoor antenna.
Japan’s Sony Corporation introduced a “wall-mounted” TV to the market: its length is 60 cm, width is 38 cm, and its thickness is only 3.7 cm, weighing only 1.7 kg, just like a mural.