Ophthalmology is the branch of medicine that deals with the anatomy, physiology and diseases of the eyeball. An ophthalmologist is a specialist in medical and surgical eye problems. Since ophthalmologists perform operations on eyes, they are both surgical and medical specialists. A multitude of diseases and conditions can be diagnosed.

The prominent opticians of the late 19th and early 20th centuries included Ernst Abbe (1840–1905), a co-owner of at the Zeiss Jena factories in Germany where he developed numerous optical instruments. Hermann von Helmholtz (1821-1894) was a polymath who made contributions to many fields of science and invented the device in 1851. Training equips specialists to provide eye care.