Space-Age Optics Based on Discovery in 1934
When he figured out a way to make exceptionally pure glass, chemist Frank Hyde knew his discovery would have myriad applications.
But who, back in 1934, could have foreseen spaceship windows, precision lenses to build ever-so-tiny computer chips, or the gossamer strands of optical fiber?
“I’m surprised at some of the things it has gone into, but I’m not surprised at the versatility of such a beautiful and useful material,” said Hyde, who at age 95 has lived to see the blossoming of a scientific discovery that lay mostly dormant until he was closing in on retirement in the 1960s.
It’s called fused silica, and it remains the most immaculate commercial glass on Earth. Hyde was a 31-year-old organic chemist at Corning Glass Works when he came up with a practical method of making it in bulk.
His inspiration? A monumental telescope being built atop California’s Palomar Mountain.
At 200 inches in diameter, its reflector would soon be the largest ever molded. Corning had won the contract to make it with Pyrex, a glass it developed in 1915 that can withstand big swings in temperature without changing shape.
Inventor Sees Fruits of Labor
Hyde’s pioneering work in the laboratory came too late to influence that project, but he knew it would eventually have far-reaching uses.
Among those he has lived to see:
* The galaxy-gazing Hubble Space Telescope;
* Space shuttle windows durable enough to shield against hazardous meteorite fragments;
* Giant optical cameras that can mass-produce microchips with 250 circuit lines printed across the width of a human hair.
All rely on a glass of such astonishing clarity that if it filled the seas, the ocean bed would be visible from the surface.
Signal-carrying laser beams can travel for miles through fused silica fibers without dissipating or scattering, a 1970s breakthrough at Corning that set in motion the fiber-optic revolution in telecommunications.
“Mother Nature usually doesn’t give you optical transparency, high mechanical strength, outstanding chemical durability, all of these things at once,” said George Sigel, professor of ceramic and materials engineering at Rutgers University. “This material provides that. It really is special.”
In the 19th century, scientists had tried melting quartz crystals to make fused silica, but that required heat in excess of 1,725 degrees Celsius, which was prohibitive. Besides, the molten glass couldn’t easily be cooled into shapes.
Hyde attacked the puzzle from an unconventional angle: He heated the basic raw materials--sources of silicon and oxygen--by running a volatile gas called silicon tetrachloride through an oxygen flame.
The ultra-pure vapors formed a fine, glassy powder of silicon dioxide that, he said, “could be pressed into a shape just like clay.”
Hyde’s vapor-to-solid method is known as frame hydrolysis. That concept, Sigel said, has since been broadened to build all kinds of high-performance materials, “an atom and a molecule at a time.”
Hyde, who grew up near Syracuse, had been hired by Corning in 1930 at a time when newly discovered plastics were threatening to usurp the place of glass.
The Palomar telescope, which drew the kind of headlines that the space race generated in the 1960s, got many scientists hunting for new materials to make even bigger mirrors. Hyde, an astronomy buff, dropped everything in 1932 to begin his fused silica experiments.
Eventually producing it in thumbnail-size lumps, Hyde pondered using the glass in a spring for measuring infinitesimal weights or as a filler in rubber. He even wondered if it might be drawn out into long fibers. But after winning his patent, he moved on to other projects.
“When an idea builds up and becomes useful, it involves the knowledge and skill of many people in different businesses,” Hyde said. “I want to emphasize that.”
Fused silica found its first real-life use in a type of radar for detecting Japanese warships during World War II.
Although Hyde’s glass is many times more resistant than Pyrex to sudden jolts of hot or cold, Corning colleague Martin Nordberg added titanium compounds in 1939 to create a zero-expansion glass used today in telescope mirrors nearly twice as big as Palomar’s.
The glass also serves as a key conduit in the semiconductor industry. Microlithographic “stepper” lenses made of fused silica provide the high transmission critical to miniaturizing computer chips.
In the early 1970s, three Corning scientists invented optical fiber, which is rapidly replacing copper as the backbone of America’s telephone, cable television and computer networks.
Optical Fiber a Winner for Corning
“Someone asked Isaac Newton, how was he so great? He said, ‘You can see further if you stand on the shoulders of giants,”’ said one of the three, Donald Keck. “Technological giants like a Frank Hyde, we just don’t applaud them enough. He’s the grandfather of the field of optical communication.”
Optical fiber is now Corning’s biggest business; the company, based in rural western New York, corners more than a third of the world’s market. But fused silica is manufactured by many companies worldwide, its sales running into billions of dollars a year.
Hyde lives alone on Marco Island off southwestern Florida. His three children visit regularly from the mainland.
“At my age, you slow down,” he said, chuckling. “It isn’t long after washing the breakfast dishes to start the dinner, that sort of thing!”
His wife of 61 years, Hildegard, died in 1991. “When you lose someone close to you like that, you really never get over it,” he said softly.
Despite his age, Hyde’s memory for scientific detail remains keen, particularly when he dwells on those halcyon days in the lab six decades ago.
“It gives you a great feeling of satisfaction that you did something useful in life,” he said. “That was an accomplishment that I can always be proud of.”
