|1981||NASA's first flight with a manned reusable rocket, the "space shuttle"|
|1989||HDTV experimental broadcasting begins, using MUSE system via broadcast satellite BS-2|
|1990||Research on the digital data compression technology MPEG-2 begins|
|1990||CCIR General Assembly establishes an HDTV studio standard recommendation (Recommendation 709)|
|1991||NHK begins HDTV test broadcasting (November)|
|1995||The Great Hanshin-Awaji Earthquake (January)|
|1998||HDTV camera installed in a space shuttle for the first time|
|2000||1125 scanning lines becomes international unified standard (March)|
|2000||BS digital broadcasting begins services (December)|
The Hi-Vision research that began in 1964 bore fruit 36 years later with the advent of digital Hi-Vision broadcasting. Today, Hi-Vision is not only used to broadcast TV programs around the world, but is also used in fields such as medicine.
1964-2000 Hi-Vision (HDTV) Becomes the International Standard
Development of Broadcasting Systems
The MUSE system, a compression and transmission system for HDTV signals that makes it possible to broadcast HDTV programs on a single satellite-broadcast channel, was constructed in 1983. It employs sub-sampling and motion compensation technology to compress data to a quarter of its original size. In 1990, research began on MPEG format, another digital data compression technique. Research continued with an investigation into the level of picture quality required for HDTV broadcasting, minimum necessary bit rate, and optimization of encoder function.
A One-hour daily experimental broadcast using the MUSE system started via the BS-2 satellite in 1989, and in 1991 was expanded to 8 hours a day of test broadcasting using the BS-3 satellite. In December 2000, digital HDTV broadcasts (BS digital broadcasting) began on 7 channels via BSAT-1b.
International Standardization of the HDTV System
An internationally unified standard for next-generation TV was a dream for most TV engineers working on HDTV systems. The first HDTV demonstration took place in the United States in 1981, and made a powerful impression with its breathtaking images. Because of the huge potential for profit with HDTV, standardization had become a significant global issue, stirring up competition between corporations, and countries. At a General Assembly meeting for the CCIR (presently the ITU-R) in May 1986, European countries pushed a 1250 scanning line and 50-field standard, but ultimately failed establish an internationally unified standard. After 1987, discussions on digital technology spurred proposals for a number of systems. However, based on the standard adopted in 1990 (ITU-R Recommendation 709), an effective number of 1080 scanning lines(adopted in 1997) and a total number of 1125 (adopted in 2000) were established as international unified standards(ITU-R Recommendation 709 revision).
A Global Presence
With digital broadcasting having gone mainstream, Hi-Vision began to spread around the world. Hi-Vision is not limited to broadcasting, and is used in various industries such as medicine. It has largely replaced the conventional television, which has only 525 or 625 scan lines.
Prototype MUSE encoder
A 300-inch large screen at the United Nations headquarters' General Assembly Hall
Making use of high-sensitivity/high-definition characteristics, HDTV has application in the medical field, such as in surgery on the retina.
"Space specification":A realistic image of the earth from space
Equipped with an HDTV camera, the space shuttle "Discovery" was launched from the Kennedy Space Center in Florida on October 29, 1998 . Working with NASA, and with the cooperation of the NASDA, NHK developed a specialized HDTV camera (VCR integrated camera) for the space shuttle. To meet the strict safety standards set by NASA, many issues had to be addressed, such as safety measures for the battery and countermeasures for electromagnetic interference. Through extensive research, NHK's engineers were able to develop a specialized HDTV camera to be used in space. That research produced 4,000 pages of results and safety measures for 28 items. The HDTV camera successfully took high definition images of Earth from space for the first time in history. Humankind could to see images of Earth from outer space in high-definition, super-realistic HDTV.
The lunar orbiter satellite "Kaguya" (SELENE, launched in 2007) is equipped with a Hi-Vision camera. The camera has shot spectacular footage of Earth-rise and Earth-set from above the moon's surface.
Astronaut Chiaki Mukai holding the Hi-Vision camera (1998.11.13)
Earth as seen from Kaguya (2008)