Snellen chart is the most common test type for recording visual acuity.
It is named after its inventor,
Herman Snellen, a Dutch ophthalmologist (19/2/ 1834-18/1/1908) from Zeist (Utrecht).
The direct ophthalmoscope was invented in the 19th century by the great German ophthalmologist
Hermann von Helmholtz. It allows the retina of the living to be examined.
The examination of the anterior segment is greatly improved with the invention of the slit-lamp in 1916.
The slit-lamp provides a high magnification and a strong light to allow minute examination of the ocular
structure especially the cornea.