Customers often ask us if they can send in existing glasses to have an FL-41 coating put on the lenses they already have. That’s exactly what Kerrie did when she first learned about FL-41. We were surprised to discover it didn't work very well. FL-41 isn’t a coating that’s added to existing lenses (like anti-scratch and anti-reflective coatings that you’re probably familiar with). Instead, it’s a tint that "soaks in" to become an integral part of the lens.

The best analogy is paint vs. dye. Say you want white fabric to become blue. Painting the fabric puts a blue layer atop the white. When you cut the fabric, you will still see white threads under the blue paint. Dyeing the fabric turns it blue throughout. When you cut dyed fabric, you no longer see white threads, only blue. A coating is like paint, while a tint is like dye. One great benefit of this is that FL-41 doesn’t come off if your lenses get scratched.

Because of the nature of FL-41 tinting, we have to start with fresh lenses. Otherwise, the coatings on existing lenses can interfere with the tint application. Also, even if lenses are not coated, normal wear and tear on your old lenses can cause invisible scratches, dings, and other imperfections. These imperfections create spots where the tint "soaks in" unevenly and becomes darker. All of a sudden, a lens that looked pristine might appear to be covered in tiny scratches! 

If you want FL-41 prescription glasses, we’ll make them for you from scratch, prescription and all. We can put them in our frames or in just about any frame you send to us. Simply click on your preferred frame style on our shop page and select "Prescription" for the lens correction type, before filling in the remaining details. You can also email or call us with any questions and/or for assistance placing an order.

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