HDTV

HIGH DEFINITION TV
The first thing we would notice in this media room is that the TV screen looks different. Today's TV receiver has been replaced by a high definition TV (HDTV) receiver. As we learned in Chapter 13 , HDTV has a wider screen and provides a sharper TV picture, one that rivals 35 mm film in quality.

History

The evolution of HDTV follows naturally from the quest of engineers to improve the quality of the television picture by adding more lines of resolution. As mentioned in Chapter 11, when TV first started, the first flickering images of Felix the Cat used only 60 scanning lines. By the mid 1930s, researchers had improved the picture by increasing the number of scanning fines to 343. In 1941, the U. S. standard of 525 fines, which gives an acceptable if not a great looking picture, was officially adopted. Europe adopted its TV standards a few years later and opted for better picture quality by using 625 scanning lines.

In the early 1970s, research into increasing yet again the number of scanning lines began in Japan as a joint effort among Sony, Panasonic, Ikegami, and NHK, the state owned television system. The result of this research was the new HDTV system, publicly unveiled at a 1981 meeting of the Society of Motion Picture and Television Engineers (SMPTE). The engineers were impressed with the picture quality but expressed concern because the new system was not compatible with existing TV sets. Two years later, SMPTE formed the Advanced Television Standards Committee to develop worldwide HDTV technical standards. The stakes were so high (cumulative sales of HDTV receivers were projected to be more than $150 billion in the first twenty years after their introduction) that political and economic factors prevented a single standard from being developed.

By the late 1980s, Japan clearly had the lead in HDTV development, with a European consortium of thirty companies (including the huge Philips and Thomson conglomerates) in second place, and the United States a distant third, primarily because only one set manufacturer, Zenith, was still American owned. The United States, however, had not given up. The FCC ruled in 1988 that no HDTV system would be adopted that was incompatible with current U.S. standards, thus shutting out the latest Japanese system from the American market. (The Japanese countered by developing a system that was compatible with U. S. standards.) Further, the Department of Defense allocated $30 million for research and development of HDTV for both consumer and defense applications and a research consortium including GE/RCA, NBC, and the David Sarnoff Research Center began studying the problem.

In 1989, the Sarnoff Research Center unveiled a system called Advanced Compatible Television (ACTV). ACTV, with 1025 scanning fines, represents a compromise between HDTV and conventional 525 line TV. Its picture is not as clear as HDTV, but the ACTV signal can be picked up on existing sets and would appear as a conventional picture. However, the additional improvement in picture quality would not be apparent unless the viewer owned a special ACTV set. Zenith also introduced its version of the ACTV system.

Finally, thanks to efforts by the State Department, the United States was able to get the International Radio Consultative Committee, the organization that allocates international spectrum space, to postpone any final decisions on HDTV until the early 1990s, thus giving the United States more time to catch up.

Technical Considerations

As it stands now, HDTV has to overcome three main problems before it gains worldwide acceptance. First, some agreement must be reached among TV production firms and users on the technial specifications of the system. The original Japanese system, called MUSE, is not compatible with any other HDTV system. (Other, more recently developed Japanese systems are compatible, however). The European system is compatible only with European technical standards and, as we have noted, the U.S. system is compatible only with U.S. sets. It is unlikely that any big set manufacturer, Japanese, European, or American, will make the huge capital investment in HDTV production unless there is a single standard for a worldwide market. Moreover, the major film and television companies would be unlikely to switch to HDTV in their productions if incompatible systems meant that they might not be able to export their programs overseas.

The second problem is how to broadcast HDTV. Recall from Chapter 13 that a regular broadcast TV channel is 6 mhz wide. Although engineers are squashing HDTV signals into tinier spaces every day, as of 1990, HDTV still requires a 9 mhz minimum channel. This means that unless some new space is found somewhere else in the spectrum, a possible but unlikely event, broadcasting HDTV will be a problem. Note that spectrum space for HDTV will not be a problem for CATV systems or for VCRs. In fact, most experts predict that HDTV sets and VCRs will be the first mass produced HDTV hardware to enter the market.

The third problem concerns marketing the new technology. No company wants to introduce a product that will make existing 525 line sets obsolete overnight. One strategy endorsed by several broadcasters and cable operators in the United States envisions a low cost ACTV system in place by the end of the 1990s. Then, by around 2000, the changeover would begin toward HDTV. By that time, argue the experts, some solution to the HDTV bandwidth problem would be found. Other countries may not follow this approach. Japan, for example, announced plans to start HDTV broadcasts in the early 1990s.

Applications

In addition to broadcast and cable TV, HDTV has other applications. The Mayo Clinic is currently using an experimental HDTV system for diagnosis in remote cites. The clarity of HDTV will also make it very attractive to those who produce medical TV programs.

Home video will be another prime market. The Japanese have already developed HDTV VCRs. The wide screen size of the HDTV set makes it a natural for movies. In addition, most HDTV VCRs are equipped with "surround sound, " a system simBar to that used in motion picture theaters.

Speaking of motion pictures, HDTV makes possible electronic cinematography. (Francis Ford Coppola has already shot two productions using HDTV.) Since its quality is close to that of 35 mm film, HDTV cameras and tape could easily replace motion picture cameras and film, thus saving motion picture production companies a lot of money. The HDTV cameras are easier to operate, the tape can be played back immediately, and, if the scene is not right, the tape can be erased and reused. In fact, some film executives are examining a system whereby, instead of shipping hundreds of separate film prints to theaters around the country, a movie company could easily distribute an HDTV version of a movie by satellite.

Forecast