525 lines

This article is about the analog standard-definition resolution. For the equivalent digital SD resolution, see 480i.
Analog TV standard by nation: countries using 525-line are in green.

525-line (or EIA 525/60) is an American standard-definition television resolution used since July 1, 1941,[1][2][3] mainly in the context of analog TV broadcast systems. It consists of a 525-line raster, with 480 lines carrying the visible image at 30 interlaced frames per second. It was eventually adopted by countries using 60 Hz utility frequency as TV broadcasts resumed after World War II. With the introduction of color television in the 1950s,[4] it became associated with the NTSC analog color standard.

The system was given their letter designation as CCIR System M in the ITU identification scheme adopted in Stockholm in 1961.

A similar 625-line system was adopted by countries using 50 Hz utility frequency. Other systems, like 375-line, 405-line, 441-line and 819-line existed, but became outdated or had limited adoption.

The modern standard-definition digital video resolution 480i is equivalent to 525-line and can be used to digitize a TV signal, or playback generating a 525-line compatible analog signal.[5]

  1. ^ Cite error: The named reference :0 was invoked but never defined (see the help page).
  2. ^ Cite error: The named reference :1 was invoked but never defined (see the help page).
  3. ^ Cite error: The named reference auto was invoked but never defined (see the help page).
  4. ^ National Television System Committee (1951–1953), Report and Reports of Panel No. 11, 11-A, 12–19, with Some supplementary references cited in the Reports, and the Petition for adoption of transmission standards for color television before the Federal Communications Commission, n.p., 1953], 17 v. illus., diagrs., tables. 28 cm. LC Control No.:54021386 Library of Congress Online Catalog
  5. ^ "What means 480i?". Afterdawn.com.