By Jane Heard Licensed Optician

What makes progressive lenses different?

Eyeglass wearers are often faced will a wide variety of choices when prescribed a progressive lens. But, did you know that all progressive lenses are NOT created equal? There are 400+ options for progressive lens designs on the Canadian market alone, and accompanying that, 400+ explanations for each lens. It’s easy to get lost in all the information.

A great fitting pair of frames paired with the correct lenses is important to realize the full benefit of progressive lenses. A lot of choice does not mean that every lens is going to give the wearer the vision they expect and require from their eyewear. Frankly, some lenses work better than others, and while one lens design might work well for one person it may not for another. In order to navigate the world of 400+ options, we need to have the answers to many questions about occupation, hobbies, and habits. Those answers are a part of the process that leads to a lens that will complement both lifestyle and (ideally) budget. In order for a progressive lens to perform optimally we must match patient visual needs with a lens design that will meet expectations.

Not everyone uses their glasses the same way. A truck driver has far different visual needs than a teacher, an airline pilot, or a computer user. In fact, each person uses their lenses differently. A professional driver is far more reliant on the distance portion of their glasses than a software engineer or a cook who will spend their day working at an arm’s length. An airline pilot needs a lens that is going to be comfortable for looking at a wide instrument panel (runways, and mountains).

Standard design progressive lenses can be thought of as a one-size-fits-all approach. These lenses work well for many people. Standard progressive lenses are a good workhorse lens, useful for everyday, but not specific to the user. These lenses require two necessary measurements be taken so as to allow for the manufacture of a lens that will work well for the long term. These are PD (pupillary distance) and pupil height.

Professional grade progressive lenses take into account 3 more measurements related to the frame. It’s all about the frame. A $1000 lens in a poor frame choice will not work as well as a $200 lens in a frame that fits perfectly. First, the vertex distance, with is the distance from the eye to the frame. Tilt or the angle the lens in front of the eye. Lastly, the wrap, or the angle the frame sits on the face.

The eyeglass frame is the link to better overall vision. Including the frame parameters with the lens order provides the wearer with a more refined progressive lens. Designing a lens with features important to the wearer means that the professional driver will be comfortable driving long hours, the software engineer will not suffer a kink in the neck from spending hours in front of a monitor, or monitors. Additionally, multiple frame measurements allow for adjustment of the prescription across the lens to account for subtle changes in prescription as the frame curves, tilts, or the distance it sits away from the face. These can affect the prescription and how the world is observed, hence why we try to fit a frame first when you get new glasses.

And to think, the discussion about coatings hasn’t even started…