Increased letter spacing and greater letter width improve reading acuity in low vision readers

Low vision readers depend on magnification, but magnification reduces the amount of text that can be overviewed and hampers text navigation. In this study, we evaluate the effects that font variations letter spacing, letter width, and letter boldness have on low vision reading. We tested 20 low-vision patients with age-related macular degeneration (AMD) and used the Radner Reading Chart, which measures reading acuity (logRAD), maximum reading speed, and critical print size. The results demonstrated a small, but measurable effect of letter spacing and letter width on reading acuity near critical font sizes.