San Francisco — It gets only about 5 percent of the American market for television sets, but it may be the option many consumers will eventually choose for home entertainment.
Called component TV, it is based on the idea of buying separate units to be hooked together for top-drawer reception. Buyers need a video monitor (TV screen), speakers, and a receiver.
The concept has been slow to catch on, industry analysts say, because of price. When added together, separate units - even though of considerably higher quality - can cost several hundred dollars more than a brand-new, top-of-the-line television set.
But experts in the business see component buying as an up-and-coming trend. The idea could get a boost in the near future if the Federal Communications Commission approves TV broadcasting in stereo (as is expected in 1984).
The best argument for individual high-quality basic components lies in the variety of possible ''plug-ins.'' In the future, these could include not only direct-drive turntables, tape decks, and amplifiers, but also videocassette recorders, home computers, video-game units, security systems, teletext (information) decoders, even laser-beam devices.
Some industry experts are not so sure the component idea for TV will become popular - mainly because it's expensive.
They also point to what happened to other electronics items. In the case of stereo and hi-fi systems - which were, and still are, offered either in complete units or as component parts - separate audio components have never reached more than about 10 percent of all stereo sales in the country.