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6 March 2014 1:04 pm ,
Vol. 343 ,
Antiretroviral drugs can protect people from becoming infected by HIV. But so-called pre-exposure prophylaxis, or PrEP...
Two studies show that eating a diet low in protein and high in carbohydrates is linked to a longer, healthier life, and...
Considered an icon of conservation science, researchers at World Wildlife Fund (WWF) headquarters in Washington, D.C.,...
The new atlas, which shows the distribution of important trace metals and other substances, is the first product of...
Early in April, the first of a fleet of environmental monitoring satellites will lift off from Europe's spaceport in...
Since 2000, U.S. government health research agencies have spent almost $1 billion on an effort to churn out thousands...
Magdalena Koziol, a former postdoc at Yale University, was the victim of scientific sabotage. Now, she is suing the...
- 6 March 2014 1:04 pm , Vol. 343 , #6175
- About Us
Fresh Eye on the Lens
5 June 1998 7:00 pm
Allvar Gullstrand, a Swedish ophthalmologist who discovered how the eye bends light to form images, was born on this day in 1862. When Gullstrand began his work, the optics of glass lenses were already well established. But it wasn't clear how the eye's lenses functioned, especially when changing focus. Gullstrand wrote out complex mathematical models and proposed that when the eye changes focus on near and far objects, it relies on more than just the curvature of the lens: Vast numbers of tiny, transparent fibers within the lens also make adjustments.
In 1911, Gullstrand also developed two tools for inspecting the eye: the ophthalmoscope for peering at the retina and optical disk; and the slit lamp, which allows doctors to locate foreign objects or tumors in the fluid of the eye. That same year, he received the Nobel Prize in physiology or medicine for his work. Gullstrand died in 1930.
[Source: Emily McMurray, Ed., Notable Twentieth Century Scientists (Gale Research Inc., ITP, 1995).]