TOKYO, FEB. 14 -- In a high-tech version of carrying coals to Newcastle, two American companies came here today to announce a new product that lets personal computers read handwritten Chinese and Japanese characters.

The $70 "Mac Handwriter," released by Apple Computer Inc. and a small California firm called Communication Intelligence Corp., lets computer users give commands or data to Apple's Macintosh computers by writing characters on a small pad. That eliminates the need for a keyboard, which is a clumsy tool for languages based on kanji (Chinese characters used as written expressions in Japanese).

This new U.S.-made gadget will have only a tiny market in the United States, but that's not the point. The Macintosh kanji-input device is part of a broad effort by U.S. personal computer makers to expand their markets overseas.

"If you want to know where the major U.S. personal computer firms are making money these days, it's not in the U.S.," said Apple Chairman John Sculley.

"In a recession market, we're all looking outside the country," Sculley said. "There really is no European computer industry, so we are doing well there. And there is tremendous growth in the Asia-Pacific region."

Japan, a wealthy, high-tech-oriented society that is about five years behind the United States in use of personal computers, holds the promise of being a spectacular personal computer market in the 1990s. But it also could be a hard one to crack; after all, this is home for some of the world's major personal computer makers, including Toshiba, Fujitsu, Epson and NEC.

Still, American PC firms are driving hard here. Ads for the Macintosh pop up on Japanese TV these days almost as frequently as those touting Sapporo beer and Sony video cameras.

Shigechika Takeuchi, president of Apple Japan, said Apple will sell about 150,000 Macintosh computers here this year. That would roughly triple 1990 sales. American companies, including International Business Machines Corp., Sun Computers Inc. and AST Research Inc., are also stepping up efforts to sell small computers here.

A key advantage that U.S. companies have is their software. Where the U.S. personal computer industry uses only two main software standards -- the Macintosh system and the DOS standard used on IBM PCs and clones -- Japan's market has been fragmented, with each maker offering its own software system.

As U.S. software packages gain popularity, Japanese makers have been forced to switch to the U.S. standard. As a result, the largest selling software program in Japan is one familiar to American PC users -- the spreadsheet Lotus 1-2-3. Lotus may lose its No. 1 position here this year, but only to another American company, Microsoft Corp., whose Windows software program is due out in Japanese this spring.

This is forcing Japanese PC makers to use the U.S-made microprocessors -- that is, the central-processing chip at the heart of the computer's circuitry -- that can run American software. When officials of Toshiba Corp. showed off their flashy new 1991 line of small computers this month, every machine on display was built around an American-made microprocessor.

The growing importance of U.S. personal computers was demonstrated vividly today when Apple opened the doors to its first Japanese "MacWorld" exposition. Every vendor booth was taken and so many potential customers poured in that the noisy, gleaming convention floor looked almost as crowded as Japanese subways at rush hour.

Amid the booming speakers and blinking screens on the display floor was a tiny booth for Communication Intelligence Corp., the Menlo Park, Calif., firm that developed the Mac Handwriter device.

Putting words into a computer is harder in Japan and China than in most other countries because the Asian giants use a writing system based on ideographic characters, or kanji. The Roman alphabet has 26 different letters; Japanese, in contrast, uses an alphabet of about 2,600 distinct "letters," or characters. No keyboard could hold them all.

Japanese computer makers have found ways to adapt. The most common approach has the user type the sound of the word using Roman letters on a standard keyboard, and then hit a "Convert" key to turn that sound into the proper kanji. It's an example of what American computer buffs call a "kludge" -- a solution that works, but one that nobody likes much.

Sony offers a pocket-sized electronic note pad that also can read handwritten Japanese, but the Mac Handwriter is the first such device that will feed directly into a full-scale personal computer.