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Liquid Crystal Display (LCD)
Fergason holds over 125 US patents in liquid crystal technology,
including the first practical use of liquid crystals. He is
perhaps best known for his discovery of the twisted nematic
field effect, which led to the creation of today's liquid
crystal display (LCD).
Fergason was born in Wakenda, Missouri in 1934. He earned
a BS in Physics at the University of Missouri in 1956, and
took a research position at the Westinghouse Research Labs
in Pennsylvania the following year. There he organized the
first American research team to study liquid crystals (1957).
Many substances emit light when electrified, but liquid crystals
are unique in that they reflect light when a current is passed
through them. These crystals were first discovered in Germany
in the 1880s, but it was not until the late 1950s that physicists
began to consider applications for them; Fergason was at the
head of the field. In the 1960s, as Associate Director of
Kent State University's Liquid Crystal Institute, Fergason
was developing a liquid-crystal-based breast cancer screening
apparatus when he made the discovery that became the basis
of his greatest invention (1967).
The liquid crystal displays then being developed in rival
labs applied voltage in "dynamic scattering mode," which consumed
too much power with poor results. Fergason used his discovery,
the "twisted nematic field effect" of liquid crystals, to
channel the current through the crystals efficiently, resulting
in displays that provided good contrast and long life on minimal
power (1969). In a typical display, the liquid crystal material
is pressed between two thin layers of glass, which are embossed
with an invisible electrode design of segmented bars that
in combination make figures. When current is applied to the
right electrodes, the crystal material reflects their ambient
light, creating a readout by contrast with the unelectrified,
and so unreflecting, surrounding areas.
Fergason had earned his first patent (#3,114,836) in 1963,
for his use of cholesteric liquid crystals in temperature
sensing applications—the first practical liquid crystal
invention. This was followed by his first patent for a liquid
crystal display (#3,410,999) in 1968, and for a "nematic liquid
crystal twist cell display" (# 3,627,408) in 1971. By then,
he had already founded a company, ILIXCO, to manufacture the
displays (1970). Fergason's first major customer was Switzerland's
Gruen Watch Company. By 1977, most digital watches featured
cool LCDs rather than glaring LEDs (light emitting diodes).
Since then, LCDs have remade nearly every type of information
display, including readouts on industrial, scientific and
medical apparatus, as well as calculators, computers, video
games and other consumer electronics.
All the while, Fergason has remained at the head of his
industry. Today, he works on miniature and passive displays,
augmented reality, and safety devices. For example, as President
of Optical Shields, Ltd., based in Silicon Valley, Fergason
created and patented eyewear whose liquid crystal material
becomes opaque instantly (in 1/20,000th of a second) when
hit by any intense radiation, protecting the wearer's eyes
even from laser light. Optical Shields' "Varilite Vision Panels"
made the company a Finalist in the 1992 Discover Awards.
To date, James Fergason himself has won over 125 US patents
and over 500 foreign patents (in over 40 countries) for his
work --- and many awards as well. Most recently (1998), he
was inducted into the National Inventors Hall of Fame.