Prism

If your eye doctor has prescribed prism correction for your glasses, you’re in the right place! Ordering prism lenses is simple once you know a few key details. This guide will walk you through what’s available, what’s not, and how to get exactly what you need.

What Is Prism Correction?

• Prism correction is used in glasses to help align your eyes properly, often prescribed for conditions like double vision (diplopia) or eye muscle imbalances. The prism bends light before it enters the eye, so your brain receives a single, clear image.

How to Order Prism

Ordering prism lenses at Zenni is easy! As long as you have a Single Vision prescription and choose a compatible frame, we can help get your vision perfectly aligned.

• Find Your Favorite Frame: Start by picking out a standard optical frame.

  • Note: To ensure the best fit for prism, please avoid sports goggles, safety glasses, and our premium wrap-around sunglass styles.

• Select "Single Vision": Prism correction is currently available exclusively for our Single Vision prescription lens types.

• Enter Your PD: An accurate PD (pupillary distance) is the "secret ingredient" for prism comfort.

• Input Your Prescription: Enter your SPH, CYL, and Axis exactly as written.

• Add Your Prism Details: Carefully enter your prism values and the base direction (In, Out, Up, or Down).

• Make Them Your Own: Once your prescription is set, you can customize your lenses and add all the bells and whistles you love.

A Quick Heads-Up on "Prism-Only" Orders

We want your new glasses to be perfect! Please keep in mind that our lab requires a prescription power (SPH or CYL) to accurately craft prism lenses. Because of the specialized surfacing required, we cannot add prism to:

• Plano Lenses: Lenses where both SPH and CYL are "0.00."

• Non-Prescription Glasses: Standard non-prescription sunglasses or readers.

If your prescription only lists prism, we recommend checking in with your eye doctor to see if a small power correction is right for you.

Is Prism Correction Available for All Types of Glasses?

• Prism correction is available only with single vision lenses and standard frame styles. This combination ensures your lenses are crafted with the precision required for accurate alignment, giving you the best possible vision and comfort.

• Prism correction requires very precise lens alignment and customization, which means it’s not compatible with certain lens types or specialty frames. We do not offer prism correction for:

  • Multifocal lenses, such as progressives and bifocals, as well as Blokz® Plus Anti-Fatigue lenses, which use subtle magnification.

  • Non-prescription lenses and readers.

  • Specialty frames, including premium sunglasses, Zunnies sports frames, ASTM-rated sports goggles, ANSI safety glasses, and VR (Virtual Reality) lenses.

Prism Pro Tips

• Enter Your Prism Values Exactly as Prescribed:

  • Prism correction involves specific measurements, including the prism power and the base direction (up, down, in, or out). It’s essential to enter these exactly as your eye doctor wrote them to ensure your lenses provide the proper correction.

• Prism Correction Should Never Be Skipped:

  • If your prescription includes prism, it’s because your vision needs it to properly align your eyes and reduce symptoms like double vision, headaches, or eye strain. Even if you prefer a certain lens type or frame, do not exclude prism just to fit those preferences. Skipping the prism can lead to discomfort or ineffective vision correction.

• Know Your Pupillary Distance (PD):

  • PD is the distance between the centers of your pupils and is crucial for aligning your lenses and prism prescription correctly. Be sure to enter your PD accurately.

  • What if I don't know my PD?

    • Ask your eye care provider for your PD (this is the most accurate option, especially for prism prescriptions). If that’s not available, you can use our virtual online PD measurement tool.

• Double Check Your Order Before Finalizing:

  • Before completing your purchase, carefully review all prescription details, prism values, PD, and lens options to avoid any errors. Mistakes can lead to incorrect lenses and require reordering.