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电视的发明和标准化已有五十几年的历史了,它主要应用于广播娱乐、新闻、体育活动等等。四十年代初,电视的基本设计已经完成,改良之后,在四十年代中期迅速应用于地面广播。四十年代末,电视在北美的月销量已达10000台。五十年代中期和六十年代中期,北美和欧洲分别引入了彩色电视广播。其后,电视系统中又进行了一些改进,如加入了多路立体声伴音,采用了回波抵销技术以减轻令人讨厌的重影等等。而电视的广播方式也变得多种多样,除地面广播外,现在有线电视广播(闭路电视),卫星直播等已经得到广泛应用。经过几十年的发展,电视机形成了一个庞大的消费电子市场,目前全世界约有10亿台电视机。
The invention and standardization of television has a history of more than fifty years. It is mainly used for broadcasting entertainment, news, sports activities and so on. In the early 1940s, the basic design of television had been completed. After the improvement, it was rapidly applied to terrestrial broadcasting in the mid-1940s. In the late 1940s, TV sales in North America reached 10,000 units a month. In the mid-fifties and mid-60s, color TV broadcasts were introduced in North America and Europe respectively. Since then, some improvements have been made in the television system, such as the addition of multi-channel stereo audio and the use of echo cancellation techniques to reduce annoying ghosting. TV broadcasting has also become more diverse. In addition to terrestrial broadcasting, cable television broadcasting (CCTV) and satellite broadcasting have been widely used. After decades of development, television sets up a huge consumer electronics market. Currently, there are about one billion TV sets in the world.