YOu are right regarding the vibrating dots. Actually, that is what makes the Optacon special compared to say, a refreshable braille display. It is actually ea

YOu are right regarding the vibrating dots. Actually, that is what makes the Optacon special compared to say, a refreshable braille display. It is actually easier to feel small structures if they are vibrating. However, one big disadvantage of that system was the resulting noise. Reading with an optacon is pretty noisy. However, it gave blind people a sort of independence that does no longer exist today. Some Optacon users did their degree with just that device, and basically no external help. These days, OCR is still not enough and you often need help from a sighted person to actually get your study material prepared.