Boston — For years, projection television sets produced big pictures but small sales.
TV buffs looking for a 61/2-foot picture could have purchased a projection TV from Cambridge, Mass., inventor Henry Kloss back in 1973. But few did.
His two-piece projection set, the first designed for home use, ''was great but strange,'' Mr. Kloss admits.
But cable television, video games, and videotape recorders have changed all that. Now a growing number of consumers will shell out $2,000 to $4,300 so they can count the whiskers on Dan Rather's chin.
''With television having more capabilities, people want a better device to display it on,'' John Reidy, an analyst with Drexel Burnham Lambert Inc., explains.
''When people are investing in disk (players) and cable and pay TV, the unit they have for display becomes entirely different and more important,'' a Zenith Radio Corporation spokesman adds.
So with an assist from improvements in technology, a spurt in projector sales ''has already begun,'' says George Kopp, editor of Video Business magazine. ''There was enormous growth in sales in 1981 over 1980.''
In fact, video projector sales more than doubled in 1981, to 121,000. And TV Digest magazine is predicting that 1982 sales will be about 200,000 units.
The recession ''is the only thing tempering (the sales explosion) at the moment,'' says Arnold T. Valencia, president of the RCA Sales Corporation. Credit for big-ticket items is tough to get, he notes. And many consumers are anxious about the economy and postponing big purchases.
As a result, there has already been some price cutting as the 19 projection TV manufacturers try to bring inventories into line. ''The next nine months in TV are going to be tough. And to a degree, projection TV could get caught in that,'' says James I. Magid, an analyst with L. F. Rothschild, Unterberg, Towbin.
Still, most industry participants are buoyed by the way sales have held up in the recession. ''The amounts sold are thrilling to contemplate,'' since the sales occurred in a recession and in tight credit conditions, Kloss says.
And sales are likely to get a boost this fall from the introduction of improved technology. ''New product introductions this year will really help,'' says David Lachenbruch, editorial director of TV Digest.
This fall a number of manufacturers, including Zenith, RCA, Hitachi, and Sony , will bring out more compact rear screen projection TVs using a smaller lens system developed by US Precision Lens Company. In this one-piece unit, the projection equipment is behind the screen.
Reducing the size of the three lenses required for such a set - one each for blue, red, and green light - ''allows you to squeeze the (TV) package into a lot smaller volume,'' says Brian Welham, vice-president of research and engineering for Precision Lens.
The new lens system will let manufacturers package a one-piece rear projection unit with a 45-inch picture into a box with the same width and depth of a 25-inch conventional TV. So it will be easier to squeeze a projection TV into the typical living room. ''It gets you a less intrusive unit,'' says Mr. Valencia at RCA.
Sony estimates that roughly 40 percent of the projection TVs sold in 1982 will be one-piece rear projection units of the type helped by the new lens technology. Another 40 percent of the market will go to one-piece front projection sets. Under Sony's scenario, the final 20 percent of the market will be taken by two-piece projection TVs on which the screen and projector are stand-alone units.
Sales of two-piece units should also get a boost this fall when Kloss Video Corporation introduces a new compact projector, about the size of a conventional 19-inch portable, which can throw its picture on a wall rather than requiring a special curved screen. ''A lot of people would have liked to buy our set but couldn't manage the six-foot screeen in their living room,'' Kloss admits.
To eliminate the screen, the distance between the projector and the viewing surface must be reduced. As a result, Kloss Video's new set will offer a 5-foot picture rather than the 61/2-foot viewing area the company has usually offered. The new projector is expected to have a retail price of $2,000, vs. the stiffer
Price is one reason the projection TV market will never rival conventional TVs in size. ''I can't see projection TV becoming an important percent of the total TV market,'' says TV Digest's Mr. Lachenbruch. Still, he expects projection TVs could eventually account for about 5 percent of the TV market, which currently totals about 11 million units.
''And (projection TV) is more imporant than the 5 percent would connote, since they are high-ticket items,'' says Valencia.
In the long run, projection TV likely will be replaced by flat picture tubes that could be hung on a wall. Sony took a step in that direction in January when it unveiled a black-and-white picture tube only 5/8-inch thick. But the screen size on the new Sony set is only 2 inches.
Getting flat screens up to wall size is expected to take at least until 1990. ''It is not a commercial horizon at all,'' Kloss says.