Snellen Eye Chart
Features
Graham Field Snellen Eye Chart
- 22" x 11"
- Chart your own eyesight
- Choose from 10 feet or 20 feet models
- Made of durable plastic
- Please note the 10 foot and 20 foot Eye Chart Differ in Appearance
Product Overview
Graham Field Snellen Eye Chart
Snellen Eye Chart
The Snellen Eye Chart is used to test visual acuity, position the patient 10 or 20 feet in front of the Snellen eye chart (depending on model chosen).
Allegro Medical presents the Snellen Eye Chart: This test measures how well you see at various distances. The eye chart itself -- the usual one is called Snellen's chart -- is imprinted with block letters that line-by-line decrease in size, corresponding to the distance at which that line of letters is normally visible.
The letters on the Snellen Eye Chart are, not surprisingly, called Snellen's test type. Each block letter is quite scientific in design (so that at the appropriate distance the letter subtends a visual angle of 5 degrees and each component part subtends an angle of 1 minute).
The 20 20 Snellen Eye Chart and the letters are named for a 19th-century Dutch ophthalmologist Hermann Snellen (1834-1908) who came up with them as a test of visual acuity. Visual acuity refers to the clarity or clearness of the vision, a measure of how well a person sees. The word "acuity" comes from the Latin "acuitas" = sharpness.
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20 Foot Eye Chart
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10 Foot Eye Chart
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Snellen Eye Chart Reviews Summary
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Part Number(s): GRH-1240, 92620


