19th century box trial frames. This set was invented by George Cox in 1838. A trial frame is used to determine an individual's lens prescription for a pair of glasses. Different ones are tried on until the correct set is found. Photographed at the Royal College of Ophthalmologists,London,UK | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library / Thomas, Mark |
Bildgröße: | 3425 px × 5138 px |
Modell-Rechte: | nicht erforderlich |
Eigentums-Rechte: | nicht erforderlich |
Restrictions: | - |