How Lenses Are Made
From creating the molds to make lens blanks to applying AR coating to prescription lenses, this guide walks you through the entire process of lens making.
It all begins with a pair of molds, one front and one back. These molds shape the lens blanks we’ll eventually use. For low-volume, custom lenses, we create glass molds in-house; cutting precise curves and polishing them to optical clarity. These molds serve as the foundation for the lens blanks.
We pour a liquid material between the molds and carefully cure it in an oven for about 22 hours. This process solidifies the lens while preventing cracks or imperfections. Afterward, the blanks are inspected for defects, ensuring a strong, clear starting point for the prescription.
In the surfacing department, the lens blank is cut to the exact prescription. Machines carve the back of the lens to create the sphere, cylinder and any progressive curves needed. Polishing smooths out the surface, and soft or hard tools bring the lens to crystal-clear clarity. This step transforms the blank into a prescription lens.
Many lenses receive a hard coating, especially polycarbonate or high-index lenses. This layer strengthens the lens and allows for a tinting later. The coating is applied with precision and is hardened using UV light, giving the lenses durability and a smooth finish.
Lenses are cut to fit your frame. Machines trim the round lens blank to the precise shape, create bevels, drill mounts if needed and ensure a perfect fit. Each lens is checked against the frame to prevent stress points or defects.
Tinting adds color and protection. Lenses are dipped into heated dye baths where the coating and lens material absorb the color. For complex tints, multiple dyes are blended to match exact shades. Every lens is checked under different lighting to ensure consistent color and proper light transmission.
The final step is adding an anti-reflective coating. Lenses are cleaned, baked and placed in Anti-Reflective coating machines where thin chemical layers are deposited onto the surface. After final inspection, lenses are mounted into the frames and undergo one last quality check before shipping.
