A 52-year-old inventor from Southern California disclosed yesterday that he has been granted a patent on computer chip technology that experts say might allow him to extract huge royalties on a wide variety of electronics products ranging from telephones to pocket calculators.

The patent award to Gilbert Hyatt, a soft-spoken electronics engineer who has spent much of the last 20 years toiling in his lab and battling the U.S. Patent Office, seems to cover the fundamental methods for combining onto a single semiconductor chip -- or collection of chips -- the basic functions of a computer.

Today such chips, known as microprocessors and microcontrollers, are at the heart of millions of personal computers and are key elements in nearly every product that employs electronics to work.

Stunned industry experts and patent attorneys said the award based on a 1968 invention sets the stage for a potentially grueling and costly battle in the courts, where Hyatt's claims likely could be challenged on technical or historical grounds.

But if he decides to seek royalties and is successful in challenging what is sure to be a well-prepared group of opponents, the financial implications could send shock waves through the computer industry and beyond, several experts said.

"It would be a big deal to every major corporation in the country, in the world," said Gary Summers, a California consultant on electronics industry litigation. Hyatt "would have the right to glean royalties from all the big corporations throughout the globe ... everybody who uses a microprocessor product."

An irrepressible inventor who lives alone in suburban Los Angeles, Hyatt said yesterday he expects to form a joint venture with a larger firm that will take on the responsibility of enforcing the new rights given him under the patent.

Although he would not be able to claim infringement on any chips made before his patent was issued last month, Hyatt could attempt to collect royalties on products sold during the next 17 years.

Personally, he said, he seeks only to gain enough financial benefit to keep his research alive. "I'm a hardworking guy with a lot of good ideas," said Hyatt, who said he works some 100 hours a week in his lab.

Hyatt said his background in aerospace led him to envision ways in 1968 to build upon what others had invented in the fast-changing field of electronics. A decade earlier, Robert Noyce at Intel Corp. and Jack Kilby at Texas Instruments Inc. had developed the so-called integrated circuit -- a method of combining thousands of transistors onto a single sliver of silicon.

Hyatt's idea, developed in the course of designing a milling machine for making metal parts, was to group together several of these specialized chips to form the guts of a computer. He further refined the idea to combine onto just one chip the key functions used to do various calculations and to store data.

Hyatt said he did all this by depleting his savings and in 1968 launching in his family-room a company called Micro Computer Inc. Ironically, two of his earliest investors reportedly were Noyce and Gordon Moore -- the co-founders of Intel. Both Intel and Texas Instruments are widely credited with marketing the first microprocessors in the early 1970s.

In fact, Hyatt never actually made his chip, but simply described it in detail in patent filings beginning in 1970. For 20 years, the inventor battled challenges from the patent office and the courts, repeatedly making filings with the office that further elaborated on his invention.

Those filings will be key to determining the impact of Hyatt's invention, attorneys said yesterday, because they may reveal that Hyatt's idea of a full-fledged "computer on a chip" did not emerge until well after other firms had staked a claim to the technology.

"The real important issue is how much of the essence of the claim appears at what stage of the chain of applications," said Ronald Laurie, a Menlo Park, Calif., attorney who has reviewed the patent.

Stuart Lubitz, former patent attorney for both Micro Computer and Intel, is skeptical about whether Hyatt's invention will turn out to be as sweeping as some are suggesting.

"I cannot believe he is the inventor of the single-chip microprocessor," Lubitz said. He said that around 1970, when several companies were doing work similar to what is described in Hyatt's patent, Hyatt himself was preoccupied with the milling machine -- not semiconductor technology.

Michael Slater, publisher of a technology newsletter, questions whether Hyatt's invention really covers microprocessors, the brains of personal computers, or whether it covers only microcontrollers, which are embedded in products like telephones and cars.

In either case, makers of such chips, like Intel, Texas Instruments and Motorola Inc., are likely to wage fierce counterattacks if Hyatt were to lodge claims of infringement against them or their customers.

Several attorneys said that at first blush Hyatt's patent seems to be unusually broad, thereby raising concerns that if he successfully defends legal challenges, it could literally rewrite the history of the electronics revolution.

For companies that thought they had sound financial grounding and a permanent place in the history books, "It spells trouble," said Roger Borovoy, former general counsel of Intel.