A<unk>  is an eye chart that can be used to measure visual acuity.<unk> s are named after the Dutch ophthalmologist Herman<unk> , who developed the chart in 1862. Many ophthalmologists and vision scientists now use an improved chart known as the LogMAR chart.
Snellen chart
Vernier acuity
Eye chart
Haller index
Dolorimeter
Amsler grid
Tinetti test
Dosimetry