I’m throwing out this “life hack” after finally, almost, dialing in my new progressive bifocal glasses so I can see acceptably well both at computer distance and long distance.
Problem ONE: lenses are fairly small. Not clear this is necessarily part of the problem, but I think it makes each of the 16 gradations in the lens smaller and therefore makes it harder to get the glasses to sit “just right” on your face. I kept the small lenses but recommend you get medium to large lenses with progressive bifocals.
Problem TWO: Reading Prescription was wrong. I have a pretty capable eye doctor so it really surprised me when I went in after initial problems. He sat me down next to his computer with hand lenses of -.25 , -.50, and -.75 diopters and had me experiment. This was VERY helpful and surprised him as we found I had more of a difference between distance and computer range than he’d measured with the instruments before.
Costco sent the specs back in at no additional charge to boost the lower portion of the bifocals. The new ones were better, but I still had problems with wavyness and inability to dial in a good focus on both eyes.
Problem THREE: Optical Center could be off as measured. In my case this was NOT a problem though it felt like it. She measured it many times and it matched earlier numbers. But have them do this if you have problems since errors here will create problems.
Problem FOUR: Optical Center could be off as the glasses sit on your face. This does appear have been part of my problem and I’m still tweaking the nose pieces to make sure vision from each eye is correct.
Problem FIVE: ANGLE of the GLASS is WRONG. THIS appears to have been my big problem. In general the glass should be parallel to your eyes, yet many frames won’t sit this way and need extensive adjustment. Before I got the new prescription this potential problem was mentioned *immediately* by the doctor and optical person so I assume it’s common. FIX: Take a small needle nosed pliers, clamp them up near where the little screws attach lenses to frame, and bend the ear pieces DOWN (or perhaps up in some cases?). Mine are now at a much different angle than they came, but the glass now is parallel to my face and therefore the glasses are working much better.
Note that 20 feet to infinity distance need the same prescription for most people.
Note that often eye doctors and especially glasses providers will often encourage you to “get used to this”. Generally I think this is very BAD advice and you should insist on working with the specs until you dial them in perfectly, or close.
Joe Duck 