I created this chart from the chart Herman Snellen developed in 1862, which is now in public domain. Search Spoonflower for 'visionchart' to see more colors/sizes/variants, and search for 'trendy1' for matching designs and solids. This design (currently set to 1200 DPI, with 1.75"x .87" charts) can also be scaled or recolored according to your needs - just Spoonmail me or leave a comment!