Allvar Gullstrand (1862-1930), Swedish professor and ophthalmologist. Gullstrand was professor (1894-1927) at the University of Uppsala, where he studied eye care and optics. He used mathematics to study optical images and the refraction of light in the eye. For this work he was awarded the 1911 Nobel Prize for Physiology or Medicine. He also studied astigmatism and improved the design of the ophthalmoscope, and designed corrective lenses for use after removal of a cataract from the eye.