Ferdinand Monoyer

Ferdinand Monoyer
Born9 May 1836
Died11 July 1912(1912-07-11) (aged 76)
Lyon, France
NationalityFrench
Occupationophthalmologist

Ferdinand Monoyer (9 May 1836 – 11 July 1912) was a French ophthalmologist, known for introducing the dioptre in 1872.

He invented the Monoyer chart, used to test visual acuity. He inserted his name in the random letters of the chart. It appears when one reads vertically from bottom to top on each side.