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Uploaded on Aug 12, 2011
Despite sophisticated techniques; Laser, intraocular surgery and contact lenses; spectacles remain the most popular method for correcting optical defects of the eye. Roger Bacon (1266) proposed that convex lenses could be used for elderly people with failing sight, replacing crystals used for magnification. Printing exploded the need for spectacles and by the close of the 20th century amazing advances in surgery corrected vision defects.
Gresham College has been giving free public lectures since 1597. This tradition continues today with all of our five or so public lectures a week being made available for free download from our website. http://www.gresham.ac.uk