Hi-Vision (HDTV) Day

What Is Hi-Vision Day?

Every November 25th is "Hi-Vision Day" (ハイビジョンの日, Haibijyon no Hi) in Japan. The day was established in 1987 by the Ministry of Posts and Telecommunications (now the Ministry of Internal Affairs and Communications) and NHK to promote Japan's High Definition Television (HDTV) technology — known in Japan as "Hi-Vision" (ハイビジョン). The date comes from Hi-Vision's 1,125 scan lines (11/25). Separately, September 16 is also a "Hi-Vision Day" established by the Ministry of International Trade and Industry. Japan was the pioneer of HDTV technology, developing the system through the 1980s that became the foundation for today's worldwide HD broadcasting.

Japan's HDTV Pioneer Role

Japan began developing High Definition Television in the 1960s, with NHK's Science and Technical Research Laboratories (NHK技術研究所) leading the effort. The Japanese HDTV standard — "Hi-Vision" — used 1,125 scan lines (compared to the 525 lines of NTSC standard definition), producing dramatically sharper images with a wider 16:9 aspect ratio that more closely matched cinema. Japan began experimental analog Hi-Vision satellite broadcasts in 1989 (with test broadcasts from 1991), making it the first country to offer regular HDTV programming, and digital Hi-Vision broadcasting began with BS digital broadcasting in December 2000.

HDTV's Global Adoption

Although Japan pioneered HDTV technology, the international digital HDTV standards that eventually became universal (ATSC in North America, DVB-T in Europe) were developed separately from Japan's analog Hi-Vision system. Japan subsequently adopted digital HDTV broadcasting, completing the transition from analog to digital terrestrial broadcasting on July 24, 2011 — a nationwide switchover that affected every household with a television and drove a major cycle of television replacement purchases.

From HD to 4K and 8K

Japan has continued its role as a television technology pioneer beyond HDTV. NHK has been developing and promoting 4K (2160 lines) and 8K (4320 lines) Super Hi-Vision broadcasting — satellite 4K and 8K broadcasts began in December 2018. Japan's 8K broadcast resolution, providing approximately 33 million pixels of image detail, represents a further extraordinary leap beyond the HD standard Japan pioneered three decades earlier.

How It Differs from September 16

The other Hi-Vision Day, September 16, comes from the 9:16 aspect ratio of the Hi-Vision screen. November 25 comes from the number of scanning lines, September 16 from the screen shape. NHK's Science and Technology Research Laboratories proposed the standard internationally in 1972 and completed the world's first 30-inch Hi-Vision monitor in 1976.

Fun Facts

• NHK's 8K research: NHK's 8K Super Hi-Vision system requires enormous data bandwidth, so advanced video compression technology was essential to make regular 8K satellite broadcasting possible.
• Olympic origins: NHK's full-scale research into high-definition television began after the 1964 Tokyo Olympics.