communicate communication disability disabled dots education eye eyesight finger school sense sight symbol text touch type visual visually word write caution go highway intersection interstate light road sign stop street street scene streets traffic traffic light traffic sign visual communication yield walk activity acuity blind chart check eyes contact cutout Doctor etdrs eye test eyes glasses isolated letters measure optic see small table tablet test vision visual acuity aid blind pedestrian blindness folding handicapped help mobility stick visually impaired bicycle cycle cycling cyclist green transport warning architecture art background kaleidoscope pattern psychedelic art symmetry visual arts abstract design design glass blue decoration decorative flower flowers textile wallpaper wrapping paper