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Phase Alternating Line (PAL) is a colour encoding system for analogue television used in broadcast television systems in most countries broadcasting at 625-line / 50 field (25 frame) per second (576i). Other common colour encoding systems are NTSC and SECAM. This page primarily discusses the PAL colour encoding system. The articles on broadcast television systems and analogue television further describe frame rates, image resolution and audio modulation. ==History== In the 1950s, the Western European countries commenced planning to introduce colour television, and were faced with the problem that the NTSC standard demonstrated several weaknesses, including colour tone shifting under poor transmission conditions, which became a major issue considering Europe's geographical and weather-related particularities. To overcome NTSC's shortcomings, alternative standards were devised, resulting in the development of the PAL and SECAM standards. The goal was to provide a colour TV standard for the European picture frequency of 50 fields per second (50 hertz), and finding a way to eliminate the problems with NTSC. PAL was developed by Walter Bruch at Telefunken in Hannover, Germany, with important input from Dr. Kruse and . The format was patented by Telefunken in 1962, citing Bruch as inventor, and unveiled to members of the European Broadcasting Union (EBU) on 3 January 1963. The first broadcasts began in the United Kingdom in June 1967, followed by West Germany late that year.〔The standard that defines the PAL system was published by the International Telecommunication Union in 1998 and has the title ''Recommendation ITU-R BT.470-6, Conventional Television Systems''〕 The one BBC channel initially using the broadcast standard was BBC2, which had been the first UK TV service to introduce "625-lines" in 1964. Telefunken PALcolor 708T was the first PAL commercial TV set. It was followed by Loewe-Farbfernseher S 920 & F 900. Telefunken was later bought by the French electronics manufacturer Thomson. Thomson also bought the ''Compagnie Générale de Télévision'' where Henri de France developed SECAM, the first European Standard for colour television. Thomson, now called Technicolor SA, also owns the RCA brand and licenses it to other companies; Radio Corporation of America, the originator of that brand, created the NTSC colour TV standard before Thomson became involved. The term PAL was often used informally and somewhat imprecisely to refer to the 625-line/50 Hz (576i) television system in general, to differentiate from the 525-line/60 Hz (480i) system generally used with NTSC. Accordingly, DVDs were labelled as PAL or NTSC (referring to the line count and frame rate) even though technically the discs do not carry either PAL or NTSC composite signal. CCIR 625/50 and EIA 525/60 are the proper names for these (line count and field rate) standards; PAL and NTSC are only the method of transmitting color to the TV. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「PAL」の詳細全文を読む スポンサード リンク
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