MARK THOMAS / SCIENCE PHOTO LIBRARY MARK THOMAS / SCIENCE PHOTO LIBRARY
Historical trial frame and lens set. Miniature travelling trial lens set from around 1900. A trial frame is used to determine an individual's lens prescription for a pair of glasses. Different lenses are inserted into the frame until the right ones or combination of ones are found. Photographed at the Royal College of Ophthalmologists, London, UK.
Model release not available. Property release not required.