for reading glasses that would be positioned down towards the end of my nose?
I’m serious.
My problem is I simply have oily hair (& eyelashes). and my regular current glasses ride very close to my eyes. Thus, the greasy eyelashes regularly brush up against the lenses and smear them. So I’m washing them 6 -8 times a day. No exaggeration.
Maybe those store-bought magnifying lenses might work. My neighbor has 4 or 5 pairs kicking around his house. Perhaps I could see how they work - on the end of my snoot.
I think you mean a prescription. The only way you could get a refraction from your ophthalmologist is if he/sge were transpatent, with an index different from 1.
I’ve studied optics for years, but not ophthalmology, which still strikes me as a Black Art. And they use different formulas than the rest of us. But I do know that the effective power of two lenses combined depends upon their separation, and if you place your glasses farther away, they won’t work as well.
I’ve never heard of greasy eye lashes (and I have incrediblt greasy hair). are you sure it’s coming fom them?
If it is due tour eyelashes, you ought to be able to move your glasses just a short distance away – you don’t need to go to the end of your nose. I doubt if any change in prescription is needed for that small a shift. If it’s a matter of keeping them steadily in that spot, it’s a mechanical, not an optical question. But I’ll bet someone has looked into it.
Finally, you can consider contacts. They won’t get messed up by oily lashes.
Are prescription reading glasses different types of lenses than the kind I bought at Costco (3 for $15)? Because I can put them on my nose or clear off my face and can’t tell any difference. I use 1.25 or 1.5 (what is that, diopters?).
I have had the “oily eyelashes problem” in the past. If you have long eyelashes and wear the lens where it will touch them then you will have that problem.
The distance from the eye will affect the prescription more as the prescription grows. Weak prescriptions will hardly be affected while stronger prescriptions will be affected more and can be compensated. In fact the ophtalmologist WILL calculate a correction for stronger prescriptions.
It’s perfectly acceptable (and ordinary) for these Black Art practitioners to use the term “refraction” to refer to a determination of the refractive condition of the patient’s eye (and therefore what lens is needed to correct any errors in refraction). May not be optically–perhaps even grammatically–correct, but it’s common to talk about getting one’s eyes refracted, or getting a refraction.
I’m giving this use a blessing. He wants a good refraction so he can get the correct prescription for glasses at an increased distance from his oily lashes.
Diopters, yes. The ophthalmologists that I work for tell patients all the time that they should go ahead and get the drugstore versions if those work for them. If your prescription in your eyes is wildly different or if you need bifocals to function well, then no.
Unless you work with different eye doctors than I’ve seen, your ophthalmologist (MD) isn’t going to do the refraction part of the exam. Optometrists (OD) typically do that.
I have very long eyelashes. When I get new glasses, the stock adjustment usually has them sitting too close to my eyes. The feeling of one’s lashes bashing against the lenses with every blink is very annoying. My optomotrist adjusts the frames so that they sit away from my lashes. I seek out frame styles that include adjustable nosepads as opposed to plastic frames that sit directly on the nose for just this reason.