The scene in Judge Rya Zobel's federal courtroom here last week was not the stuff of TV melodrama. But with the witness stand occupied by the man who may be America's foremost businessman-inventor - and with hundreds of millions of dollars riding on the outcome - it was no ordinary trial, either.
On one side is Polaroid Corporation, a company still largely dominated by its founder, Dr. Edwin H. Land, the acknowledged inventor of ''instant'' photography. On the other side is Kodak, the Rochester, N.Y., photographic giant that is the 29th-largest industrial corporation in the United States.
At issue is whether Kodak infringed any of 10 separate patents when it introduced its first instant camera in 1976.
The trial began two weeks ago, after five years of legal maneuvering by the two companies, and is expected to last at least another month. Its outcome will determine how easy it is for Kodak or anyone else to carve out part of the instant-camera market - and how much, if anything, they must pay Polaroid for the privilege of competing with it.
That is of more than passing interest to Polaroid in particular. Nearly all of the Cambridge, Mass., company's $1.5 billion in annual sales consists of instant cameras and - the more lucrative end of the business - the film that goes in them. Both Polaroid's and Kodak's instant cameras will only accept film supplied by the manufacturer.
For most of its corporate life, Polaroid had the picture-in-a-minute field all to itself. Since most amateur photographers saw Dr. Land's early cameras as a big-ticket item, Kodak was content to supply Polaroid with color negative material for its film. Its real interest was concentrating on mass sales of cheap, easy-to-use conventional cameras like the highly successful Instamatic.
In 1965, though, Polaroid introduced the Swinger, an instant black-and-white camera that cost only $14, and four years later was selling a color camera for $ 30. Kodak kicked its own research-and-development program into high gear and in 1969 the company informed Polaroid it would no longer manufacture Polaroid's film.
For a while it seemed as if there would be no contest. Polaroid's SX-70 model , introduced in 1972 and dubbed by Land ''absolute one-step photography'' - took a brighter, clearer picture than previous instant cameras, and did so without requiring the photographer to pull out the picture, peel apart the exposure, or indeed do anything at all other than push the button. Kodak, which had been developing a system requiring a peel-apart film, had to send its engineers back to the drawing boards.
Instant photography, however, can be a fickle market. Polaroid faced initial quality-control problems with the SX-70, and the recession years of 1973 and '74 made consumers reluctant to spend money on luxuries like instant cameras.
Ironically, it was Kodak's entry into the market in 1976, as well as the recovering economy, that helped put Polaroid's sales back on course. ''Competition between Kodak and Polaroid has seemed beneficial to both companies ,'' Financial World observed, ''keeping management on the run and increasing the volume of advertising, which is selling the whole idea of instants to an ever-increasing number of consumers.''
Yet recently Polaroid's sales have begun to drop off again - 1980 instant-camera shipments were down some 2 million from 1978, according to the industry's authoritative Wolfman Report - and third-quarter earnings for 1981 are off. That may account for the two companies' inability so far to settle the case out of court. ''Polaroid would like to see Kodak pay hundreds of millions of dollars in royalties,'' an industry analyst said, ''and Kodak is probably willing to pay only tens of millions.
So far, Dr. Land has been the only witness, and his presence has dominated the courtroom. Land, who is 71 but looks considerably younger, spoke softly as Polaroid lawyers led him gently through a history of his many discoveries and patents.
His tone changed, however, when Kodak lawyer Frank T. Carr challenged him to show, in effect, how his inventions differed from what is known among patent specialists as prior art - that is, what everybody else working in the field knew at the time also. ''There is no simple answer to your simple question,'' Land told Mr. Carr abruptly at one point, and at another he described a chart of a film unit prepared by Carr's staff as ''an exact statement of the wrong way to do it.''
Judge Zobel, who is hearing the case without a jury, will have to decide the outcome on the basis of highly technical claims and counterclaims - one reason Perry Mason would not have felt at home in her courtroom last week. So far, in fact, the courtroom has seemed much like a classroom, with the judge the only student and Land and the lawyers the only teachers.