Geroge Heilmeier's career was made of classified projects. He would at some point work for the government on stealth bombers and the like, and at DARPA, one of the agencies best known for its secret groups. But one of his first projects, while he worked the private sector at RCA, was classified, too.
In the 1960s, Heilmeier was working in technology that could slim down bulky TVs into flat-panel wonders. As he later told Businessweek:
[F]lat-panel TV was the holy grail of the whole TV industry at that time. That's why RCA immediately classified my project in 1964.
He and his colleague were working with a remarkable substance: liquid crystals. These crystals had first been identified in the late 1800s and although, like liquid, they would take the form of their container, unlike most liquids, their molecules would align. By the time Heilmeier started working on creating the first LCD display, one of his predecessors at RCA had shown how, with a little electricity, the crystals could be coaxed into particular patterns. Heilmeier found that certain types of crystals could be pushed further and that, by applying current to them, he could control the amount of light they reflected.
This technology was what made the first LCD work. More than 40 years later, Heilmeier told NPR:
The first time [we saw an LCD display work] really got us excited. It was an alphanumeric display and we could display numbers from one to 10 and then we essentially demonstrated that we obviously could do letters as well as numbers. And we looked at the contrast and the quality of the imagery and the like and we felt that we had something there.
The day after Heilmeier and his colleagues announced their discovery in 1968, The New York Times reported that "among the benefits that might ultimately result from the development" was "a thin television screen that can be hung on the living-room wall like a painting." It took decades for that to become a reality (today's LCD screens rely on a different type of liquid crystal behavior than Heilmeier's did)—but now about 200 million are sold every year.