March 22, 2019 Eye Associates

What the Heck is a Phoropter?

If you’ve ever had an eye exam (we hope you have!), you’ve probably wondered about the big piece of equipment you look through to answer “which is clearer: 1 or 2?” questions. It’s called a phoropter, and is one of your eye doctor’s most important diagnostic tools.

What Is a Phoropter?

Though it sounds like it, a phoropter is not a type of dinosaur! It is an ophthalmic testing device (also called a “refractor”) that contains a variety of lenses used for refraction of the eye during an eye exam. In use since the early 1900s and originally called a “phoro-optometer,” the phoropter ensures that your eye doctor is able to determine the exact vision correction needed (if any) by your individual eyes. In addition to measuring refractive error, it also measures ductions and phorias (the root of “phoropter”), which are the characteristics of binocularity (how the eyes work as a team).

How Does It Work?

The eye patient sits behind the phoropter and looks through it at an eye chart. Your eye doctor changes lenses and settings while asking for subjective feedback on which options help you see the image most clearly.

The phoropter helps to determine “refraction” – how uniquely curved and shaped a lens must be to correct your vision to as close to 20/20 as possible. The phoropter also helps your doctor check binocular vision (how well your eyes work together) and determine the muscle coordination in your eyes.

Your eye doctor will ask multiple times which of two images is clearer (“1 or 2?”). Your answers, in conjunction with the phoropter’s readings, will help ensure your eyeglass or contact lens prescription exactly matches your needs so you can enjoy clear vision every day.

Time for a New Prescription?

It’s normal for your eyes to change over time. Just because you may wear glasses doesn’t necessarily mean they are the right prescription for your current needs. As part of your routine health care, it’s important to have your eyes regularly examined to recheck your vision for any changes or early signs of any eye diseases. The phoropter can help!

We value our long-term family relationships and are proud of our satisfied patient testimonials. Contact us to have an Eye Associates professional take care of your eye health!

The information in this article should not be used for medical advice, diagnosis or treatment. As always, you should consult with your health care provider about your specific health needs.

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