This Snellen chart includes Red and Green color bars for an easy and helpful color vision test Screens for Amblyopia Snellen optotypes date back to 1862, when Herman Snellen released his first eye test in England. These Snellen optotypes have changed little throughout the years and are used regularly today. These optotypes feature strong serifs and follow idea of the 5x5 grid. Snellen chart is also coupled with red and green stripes for an easy color vision test