Insects with compound eyes have a different perceptual apparatus than bifocal vision creatures like humans do, and their manner of perceiving the world is very different from our own.
Historically, the only corrective option was wearing bifocals that allow for close viewing, as well as far-viewing capabilities when you look up from the bifocal area.
This created a giant bifocal system which allowed him to see the blackboard through the right side, then use the left side to write down what he had seen.