Hdtv history

The term high definition television was also used to refer to television standards developed in the 1930s to replace the early experimental systems, although, not so long afterwards, Philo T. Farnsworth, John Logie Baird and Vladimir Zworkin had each developed competing TV systems but resolution was not the issue that separated their substantially different technologies. It was patent interference lawsuits and deployment issues given the tumultuous financial climate of the late 20′s and 30′s. Most patents were expiring by the end of World War II leaving the market wide open and no worldwide standard for television agreed upon. The world used analog PAL, NTSC, SECAM and other standards for over half a century.

Standard resolutions. Visual comparison of common TV display resolutions.

Note: this graphic ignores the impact of interlaced artifacts, which would further reduce the vertical resolution

NTSC is typically 720×480

Standard frame or field rates

* 24p (cinematic film)

* 25p

* 30p

* 50p

* 60p

* 50i (PAL)

* 60i (NTSC)