A modified letter matching chart for testing young children's visual acuity.

A new chart for testing children's visual acuity was designed. It was based on the matching principle and showed rows of the four letters H, O, T, and V at a distance of 3 m. A geometric progression of leter size was used. In order to disclose the crowding phenomenon, the distance between letters was equal to the letter width in each line. Fifty children's testability and visual acuity was studied with this chart and an E chart. It was found that the children performed better when the letter matching chart was used and that the letter matching visual acuity values were higher in about 2/3 of the eyes. The more interesting matching game and the closer viewing distance are possible causes of these differences.