Is there a difference in the lens for right vs. left eye. In other words if someone’s prescription is the same for the right and left eye, are the lenses interchangeable and basically the same, or does it still matter which one goes into which eye?
I use the same lenses for Right and Left. There is no difference for me. At points in my past I’ve had different prescriptions for each eye, and that was the only time I had to be careful to keep right with right and left with left.
I have such a prescription and, in my case, it doesn’t matter which lens goes into which eye.
Not only does the script have to be the same but also the size or the lens.
Mine are identical so it doesn’t matter. The optometrist did advise me that it’s good practice to keep the same one in each eye. Makes it easier if you do end up with different lenses later on.
As long as the power, size and base curve are the same, you can swap them around. We’re talking about run-of-the-mill disposables or soft extended-wear lenses, right?
For most people, size (diameter) and base curve will be the same for both eyes.
If you’re dealing with exotic things like hard or semi-rigid lenses, or prescriptions for bifocal or astigmatism, then you have to pay attention, even if the lenses have the same basic power.
My lenses are different and are marked accordingly on the box and the holder. The size, etc. are the exact same, but the strength is slightly different. I made the mistake of getting the lenses backwards once and got an incredible headache. Lenses out and the headache disappeared.