What's the machine optometrists use to estimate your prescription?

Question

Some optometrists have a machine that can estimate your prescription. You look inside, and it measures your eye while you watch a shape that goes in and out of focus. I'd like to try one of these machines at my next eye exam, but I don't know what to ask for. What are these machines called? Thanks!

Answer 1

Autorefractor.

Answer 2

it's called an autorefractor but most optometrists will do this even if you don't ask just because it gives them a general idea of where your prescription should be. they will still do a refraction, which is where they get your actual prescription and you look through the lenses and they ask is one better than two, two better than three, that whole thing. These are all parts of a regular eye exam