NEW YORK, July 31, -- Flat panel displays will have a $27.2 billion market by 2002 -- almost twice what it was just three years ago -- said Technical Insights, a unit of John Wiley & Sons Inc. The study reported on the use of displays in the electronic information and communications industries. They come in a range of sizes-from animated sports arena billboards to tiny watch faces, says Leo O'Connor, editor of the Technical Insights reports program. They can be monochrome or full color; cathode ray tubes, projectors or flat paneled; and cheap as sand or worth millions. Compared with the cathode ray tubes used in televisions, flat panel displays are more compact and efficient, and are being used more and more by an ever-increasing global market, the report said. Computers -- mainly laptops, notebooks and other hand-held devices that use liquid crystal displays -- represent the largest demand for the displays.