How Your Eyeglasses Are Made

There’s a lot that goes into a pair of eyeglasses. Here’s just a brief overview:

Data Gathering: A Chat with your Registered Optician

We start with your prescription and a chat. This is when we find out how you use your eyeglasses (eg. for driving, working on a computer, sports, etc.) This will help us order the appropriate lenses and features to match both your lifestyle and budget.

We will also take specific measurements (like the distance between your pupils). We’ll need this information later when cutting your lenses.

Lens Manufacturing

Once ordered, your lenses start their journey. They are ground from high-precision machines and materials, mainly plastic. (Glass holds few optical advantages over plastic, and they’re heavier and more dangerous due to shattering, too.)

During the grinding process, digital computations place optical corrections on the surface of your lens on the scale of nanometers (that’s precision at every 1/100,000th of a millimeter!) It’s like having a bug’s compound eye, each little correction catching the light individually and refocusing it for your eye in an unprecedentedly accurate way.

After grinding your prescription into the lens material, coatings are applied (this is what takes the longest time). These coatings are essential for cutting glare, reducing harmful blue light, blocking UV light, and making the lenses scratch resistant.

Cutting Your Lenses

Once we receive your lenses, we check them for accuracy. If all checks out, we combine measurements from the frame with those from your face and use them to figure out the positioning of your lenses within your frame (so the light being focused by the lenses is properly directed to your pupils).

We plug this data into our machines, adjust a few settings, start the cutting. During this process we are able to make customizations such as changing the shape of your frame and lenses. We also make some manual corrections including manual cutting (because machines are great, but nothing beats the precision of a trained technician!).


Once finished, your eyeglasses undergo a 16-point check, and then it’s finally time to try them on!

We make sure your frame sits properly and comfortably on your face, and that the lenses are properly lined up with your pupils. If they are comfortable, if they don’t slip off your face, and if your vision is crisp, then we’re done and you’re on your way!

But remember: We’re always here to help with any future adjustments or questions!

Precision Optics Requires a Careful Eye

Some of the things we check when we cut your lenses:

  • Lens Basics
    • Material is accurate to order (Index and Substrate?)
    • Lens Thickness (Center and Edge Thicknesses for both aesthetics and safety)
    • Base Curve (Balanced? Appropriate for frame and Rx?)
  • Coatings / Tints
    • Coat is accurate to order (UV protection, Blue-filter, AR vs no-AR, etc.?)
    • Free of Defects (No Pooling, Discolourations or Pit Marks)
    • Proper Tints and Treatments (including Photochromic and Polarization Angle)
  • Prescription
    • Basics (Sphere, Cylinder, Axis, ADD)
    • Prism (including Balancing)
    • Compensated (Digital) Rx is accurate
  • Lens Design and Measurements
    • Lens Design
    • Corridor
    • PD
    • OC Height
    • Free-form digital analysis
  • Edge and Mounting
    • Bevel/Groove placement
    • Swarf (polycarbonate and trivex lens debris) cleaned off
    • Overall fit of lens (doesn’t pop out)
    • Bench alignment
    • Rx re-verified in frame
    • PD/Height re-verified in frame
    • Free of scratches
    • Cleaned and sanitized

Want a Tour?

If you’re interested in optics and want to learn more, give us a call. We’d be happy to arrange a bit of a tour where you can see for yourself what the process looks like! Just ask for David 🙂