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.
发展历程
1883年圣诞节
德国电气工程师尼普科夫用他发明的“尼普科夫圆盘”使用机械扫描方法，作了首次发射图像的实验。每幅画面有24行线，且图像相当模糊。
1908年
英国肯培尔.斯文顿、俄国罗申克夫提出电子扫描原理，奠定了电视技术的理论基础。
1923年
电视的发明者之一美籍苏联人兹瓦里金（又译维拉蒂米尔·斯福罗金）发明静电积贮式摄像管。1923年发明电子扫书描式显像管，这是电视摄像术的先驱。
1925年
英国约翰.洛奇.贝尔德，根据“尼普科夫圆盘”进行了新的研究工作，发明机械扫描式电视摄像机和接收机。当时画面分辨率仅30行线，扫描器每秒只能5次扫过扫描区，画面本身仅2英寸高，一英寸宽。在伦敦一家小商店向公众作了表演。
1926年
电视的发明者之一贝尔德向英国报界作了一次播发和接收电视的表演。
1927——1929年
贝尔德通过电话电缆首次进行机电式电视试播；首次短波电视试验；英国广播公司开始长期连续播发电视节目。
1930年
实现电视图像和声音同时发播。
1931年
首次把影片搬上电视银幕。 人们在伦敦通过电视欣赏了英国著名的地方赛马会实况转播。电视的发明者之一美国人费罗·法恩斯沃斯发明了每秒种可以映出25幅图像的电子管电视装置。
1936年
英国广播公司采用贝尔德机电式电视广播，第一次播出了具有较高清晰度，步入实用阶段的电视图像。
1939年
美国无线电公司开始播送全电子式电视。瑞士菲普发明第一台黑白电视投影机 。
1940年
美国古尔马研制出机电式彩色电视系统。
1949年12月17日
开通使用第一条敷设在英国伦敦与苏登.可尔菲尔特之间的电视电缆。
1951年
美国H.洛发明三枪荫罩式彩色显像管，洛伦期发明单枪式彩色显像管。
1954年
美国得克萨期仪器公司研制出第一台全晶体管电视接收机。
1966年
美国无线电公司研制出集成电路电视机。3年后又生产出具有电子调谐装置的彩色电视接收机。
1972年
日本研制出彩色电视投影机。
1973年
数字技术用于电视广播，实验证明数字电视可用于卫星通信。
1976年
英国完成“电视文库”系统的研究，用户可以直接用电视机检查新闻，书报或杂志。
1977年
英国研制出第一批携带式电视机。
1979年
世上第一个“有线电视”在伦敦开通。它是英国邮政局发明的。它能将计算机里的信息通过普通电话线传送出去并显示在用户电视机屏幕上。
1981年
日本索尼公司研制出袖珍黑白电视机，液晶屏幕仅2.5英寸，由电池供电。
1984年
日本松下公司推出“宇宙电视”。该系统的画面宽3.6米，高4.62米，相当于210英寸，可放置在小型卡车上，在小街和广场等需要的地方播放。系统中采用了松下独家研制的“高辉度彩色发光管”，即使是白天，在室外也能得到色彩鲜艳，明亮的图像。
1985年3月17日
在日本举行的筑波科学万国博览会上，索尼公司建造的超小屏幕彩色电视墙亮相。它位于中央广场上，长40米、高25米，面积达1000平方米，整个建筑有14层楼房那么高。相当一台1857英寸彩电。超小屏幕由36块小型发光屏组成，每块重1吨，厚1.8米 4行9作品共有45万个彩色发光元件。通过其顶部安装的摄像机，可以随时显示会场上的各种活动，并播放索尼公司的各种广告性录像。
1985年
英国电信公司（BT）推出综合数字通信网络。它向用户提供话音、快速传送图表 、传真、慢扫描电视终端等。
1991年11月25日
日本索尼公司的高清晰度电视开始试播：其扫描线为1125条，图像质量提高了100%；画面纵横比改传统的9：12为9：16，增强了观赏者的现场感；平机视角从10度扩展到30度，映图更有深度感；电视面像“画素”从28万个增加 为127万个单位面积画面的信息量一举提高了近4倍……因此，观看高清晰度电视的距离不是过去屏高的7倍而是3倍，且伴音逼真，采用4声道高保真立体声，富有感染力。
1995年
日本索尼公司推出超微型彩色电视接收机（即手掌式彩电），只有手掌一样小小 ，重量为280克。具有扬声器，也有耳机插孔，液晶显示屏约5.5厘米，画面看来虽小，但图像清晰，其最明显的特点是：以人的身体作天线来取得收视效果，看电视时将两根引线套在脖子上，就能取得室外天线般的效果。
1996年
日本索尼公司推向市场“壁挂”式电视：其长度60厘米、宽38厘米，而厚度只有3.7厘米，重量仅1.7千克，犹如一幅壁画。
development path
Christmas 1883
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.
1908
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.
1923
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.
1925
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.
1926
Baird, one of the inventors of television, gave a broadcast and reception performance to the British press.
1927-1929
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.
1930’s
Realize the simultaneous broadcasting of TV image and sound.
1931
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.
In 1936
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.
1939
American Radio Corporation began to broadcast all-electronic television. Swiss Philip invented the first black and white TV projector.
1940
U.S. Guerma developed an electromechanical color television system.
December 17, 1949
The first TV cable laid between London and Suden Calfelter was opened.
1951
American H. Lowe invented a three-gun shadow mask color picture tube, and Lorenian invented a single-gun color picture tube.
1954
Texas Instruments Corporation of the United States developed the first all-transistor television receiver.
1966
American Radio Corporation developed integrated circuit televisions. Three years later, a color television receiver with an electronic tuning device was produced.
1972
Japan developed a color TV projector.
1973
Digital technology is used in TV broadcasting, and experiments prove that digital TV can be used in satellite communications.
1976
The UK has completed the study of the “TV Library” system, and users can directly use the TV to check news, books, or magazines.
1977
Britain developed the first batch of portable televisions.
1979
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.
1981
Sony Corporation of Japan has developed a pocket black and white TV with a 2.5-inch LCD screen and battery-powered.
1984
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.
1985
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.
1996
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.