Ophthalmic OCT (optical correlation tomography of the eye) is a diagnostic aid in ophthalmology that is very widely used and can be of great help to ophthalmologists. It is mainly used in two ways: one for corneal disease and another for fundus disease, which can show the structure and subtle changes at all levels of the cornea, and can be very helpful for doctors of corneal disease. It is more used for diagnosis and differential diagnosis of fundus diseases, such as common macular diseases, macular degeneration, macular fissure, macular anterior membrane, vitreous macular traction syndrome, etc. The diagnosis of these diseases requires OCT examination results. There are also auxiliary examinations of optic disc atrophy, optic disc microsaccades, and optic disc diseases, which also rely on OCT findings for diagnosis and differential diagnosis.