Snellen Distance Vision Eye Chart

20 Feet Size 22 x 11 Inches.

DESCRIPTIONS:-

These Snellen Eye Chart was originally introduced in 1862 by Herman Snellen. The Snellen eye Test uses the idea of subtended 5 minutes of arc with a 20 Feet distance. This became the "Standard Vision" measurement. Also, Snellen developed the idea of a 5 x 5 grid for a standard for his optotypes. Each Optotype must meet certain percentage requirements in this grid before it is used for testing. This helps to make a uniform and equal vision chart. The Snellen eye test is the basic many othere vision tests.

Specification:-

Non reflecting, matte finish eye Charts, Designed for Vision Testing at 20 Feet distance.

Eye Chart measures 22 x 11 in.

Plastic Washable Sheet.

Wall Hanging Whole for easy hanging.

Disclaimer: 

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