Our most frequently asked questions, answered for your benefit. Need further assistance? We're available by phone Monday - Friday, 8 a.m - 5 p.m PST and by email every day 8 a.m - 5 p.m PST.


We offer a wide range of lenses for optical and non-optical use. We offer optical lenses in the form of Single Vision and Progressive. Optical Lenses include: CR-39, 1.52 Index Polycarbonate, 1.67 Index. Transition Lenses are available as an option and you can also custom tint your optical lenses to make them into sunglasses. Non-Optical sun lenses are available in CR-39 and Polycarbonate. Mirror coating and Polarized lenses are available as options.

How do i find my prescription?

To get your prescription, please contact your local optometrist. Eye exams are also performed at many local optical stores by licensed opticians.


Once you have your prescription from your optometrist, you will be able to input your prescription information after you have selected the frame you want to purchase. DIFF also requires that you submit a photo or scan of your prescription so we can confirm we have all the necessary information to get your lenses created.

how do i find my pupillary distance (PD)?

Your PD is the distance between your pupils, and it helps us center your prescription correctly in your frames. It's important to note that the average PD is between 57 and 65mm. For progressive lenses, you may need two PD values - one for each eye. It is best to get this measured by your eye care professional. If your doctor did not include this measurement with your prescription, follow these easy steps to fid your PD before you start your order:

Please note: We're unable to fill expired eyeglasses prescriptions and prescriptions for contact lenses. If your doctor provided an expiration date on you prescription, we will always abide by the doctor's orders. If your doctor did not provide an expiration date, we'll adhere to the optical rules of the state where your prescription was written to determine if we're able to fill it.

what's the best way to clean my lenses?

To clean your lenses, simply rinse them with a mild dish soap and lukewarm water, and dry them with a soft cloth. For day-to-day cleaning of light smudges, a few swipes of the pouch included in your case should do the trick. Please be careful to avoid using hot water on your lenses (especially if they are high-index lenses), as they can develop bubbles or cracks when exposed to high heat.