405-line Television System
The 405-line monochrome analogue television broadcasting system was the first fully electronic television system to be used in regular broadcasting.
It was introduced with the BBC Television Service in 1936, suspended for the duration of World War II, and remained in operation in the UK until 1985, and was also used between 1961 and 1982 in Ireland as well as from 1957 to 1973 for the Rediffusion Television cable service in Hong Kong.
Sometimes called the Marconi-EMI system, it was developed in 1934 by the EMI Research Team led by Sir Isaac Shoenberg. The figure of 405 lines had been chosen following discussions over Sunday lunch at the home of Alan Blumlein. The system was the first broadcast system in Britain to use interlacing, though EMI had been experimenting with a 243 line all-electronic interlaced system since 1933. In the 405 system the scanning lines were broadcast in two complementary fields, 50 times per second, creating 25 frames per second. The actual image was 377 lines high and interlaced, with additional unused lines making the frame up to 405 lines to give the slow circuitry time to prepare for the next frame; in modern terms it would be described as 377i.
At the time of its introduction the 405-line system was referred to as "high definition", which it was compared to earlier systems, although of lower definition than 625-line and later standards.
Read more about 405-line Television System: History, System A, Experimental Colour Transmissions
Famous quotes containing the words television and/or system:
“It is among the ranks of school-age children, those six- to twelve-year-olds who once avidly filled their free moments with childhood play, that the greatest change is evident. In the place of traditional, sometimes ancient childhood games that were still popular a generation ago, in the place of fantasy and make- believe play . . . today’s children have substituted television viewing and, most recently, video games.”
—Marie Winn (20th century)
“Columbus stood in his age as the pioneer of progress and enlightenment. The system of universal education is in our age the most prominent and salutary feature of the spirit of enlightenment, and it is peculiarly appropriate that the schools be made by the people the center of the day’s demonstration. Let the national flag float over every schoolhouse in the country and the exercises be such as shall impress upon our youth the patriotic duties of American citizenship.”
—Benjamin Harrison (1833–1901)