Why we ask one, or two? forty times

Refraction is how we find your prescription: two lenses, one after the other, and a simple question. Better one, or two?

We ask it about forty times because each answer narrows the range. First the sphere, then the cylinder, then its angle, each eye on its own and then together.

There are no wrong answers

If one and two look the same, say so. That is useful: it means we are close. Most people worry about getting it wrong. You can’t.