HomeBlogWhat are prism glasses?

Most people need vision correction.

It’s true. In fact, at least 60% of the world’s population requires some form of vision correction in order to see properly. This correction can come in many forms and a prism value in your prescription can be one of them.

In the eyeglass world, a prism is primarily used for correcting double vision. This can be achieved by either positional correction or convergence correction. Stay with us, it’s not that complicated.

What is Double Vision?

The medical term for double vision, diplopia, occurs when a person sees two identical images when using both eyes, instead of just one image. Sometimes, people who have blurred vision have diplopia, as the images they see are only slightly separated – resulting in ‘fuzziness’.

Why do some people have double vision?

Binocular double vision (using both eyes) usually occurs when the muscles around the eye, which move your eyes up, down, left and right, don’t work properly. Because of this, the orientation of both eyes isn’t focused on the same image, which is why people with double vision see two images. Keep in mind, there are some other causes for double vision, so if you’re experiencing this phenomenon, we definitely recommend getting checked out by an eye doctor.

Prism lenses

How do prism glasses work?

Prism lenses are essential to getting your eyes working together! No one wants double vision, right? The lenses work by fooling your brain into thinking your eyes are seeing 1 image again, instead of two. They do this by using the properties of a prism to bend the image to a place where your brain can process it more easily.

So how does a prism work then?

Scientifically speaking, Prisms are a transparent optical element with flat, polished surfaces. They work by refracting light. To you and us, that means they bend light from the straight path it travels into another path. This is how prism lenses ‘trick’ your brain into combining both images your eyes see into 1 single image. Pretty smart, huh?

So, where do I get Prism eyeglasses?

This is the easy bit! Choose your favorite EyeBuyDirect frames and enter your prescription, which will, of course, include your Prism Value and tah dah! Your beautiful new pair of corrective prism glasses will be made in our lab and sent straight to your door. It couldn’t be easier.

Here’s to single image vision,

Tom