We had a patient who got AR on her lenses for the first time. She returned a couple weeks later complaining that ever since she got the glasses, things were too bright. Now, my understanding is that AR allows more light to pass through the lens, but I was really surprised that someone could be so sensitive as to not only notice that, but also be bothered by it. We've never had that problem with anyone else. Has anyone else had a patient who couldn't tolerate AR?
No I haven't. It lets more light transmission in, but it does not make things brighter, in my opinion, maybe clearer, but not brighter. Take a look at her old lenses. Do they have transitions, a tint, or even are they too scratched up?
One option is transitions.
Think about this. We are selling AR with the propositon that the patient will get more light. Now we are saying we doubt the patient can preceive the extra light. Are we pushing something a little fishy here?
Chip
This is PURE THEORY from a NON-OPTICAL DUDE, but perhaps the patient over a period of some years became adapted (psychologically accustomed) to the slightly degraded vision that could be expected from lenses without AR -- especially higher index plastic lenses, if that's what the patient had been using. Suddenly the somewhat increased clarity and/or brightness of AR lenses is introduced and the patient isn't expecting it, so it seems like a "problem" at first. That's my 0.02 dollars!
The Great Karnac explores a scientific paradox involving the Washington Redskins. Follow the PURPLE web link to The Great Karnac.
I agree with the non-optical dude and For-Life. It could be that the patient got used to the compromised acuity looking through tinted, scratched or off power lenses and can't get used to the clarity of their new lenses.
Especially at night, all of the above create the effect of looking at things with dim headlights on your car - all of a sudden things are a bit sharper.
I would imagine that if people who are 20/15 feel that something is wrong with 20/20 then folks who see 20/20 after being in the opposite direction could also feel they aren't seeing right.
PS - paw, good to see you posting again! :)
Spexvet started a thread a few weeks back that also has some potential relevance to this question. It's a discussion of a theoretical connection between AR coating and Abbe (chormatic aberration.) The first several post are relevant, then it digresses onto a slightly different topic.
http://www.optiboard.com/forums/showthread.php?t=10606
I have seen it several times, working at an md's office we deal with cateract patients alot. Pre and post removal. I doesnt happen often but it does happen.
Paul:cheers:
Everything is brighter. That's what an AR does. The light loss due to reflection is cut from 7% (in CR more in higher index materials) to between 1 and 3%, ergo 5% or more additional light reaches the eye.Originally Posted by chip anderson
Now, while an average person (really anyone without significant vision loss) is able to distinguish this difference in transmitted light in a side by side comparison and could probably distinguish the difference swaping glasses it's rather unlikely that over the 2 or 3 day period of adjustment to new glasses they'd still be aware of this improved transmission.
I posit two possibilities: first their previous lenses lowered transmission lenses (see above posts); second the AR has a non-standard transmission spectrum leading to the 'enhancement' of particular colors (actually the deadening of others) and the wearer is particularly sensitive to this shift. Scenario one is vastly more likely.
I'd be very interested in the resolution of this issue. Please keep us up to date.
I have had some cases where the polished lens edge created an internal reflection that bothered the patient. Just something to check.
:cheers: Life is too short to drink cheap beer.
What I said is that the AR will make objects clearer, because the light it transmits is less distorted. However, it does not let in some much light that it makes it too bright. I mean if you look at a light tint it repeals 20 percent of light, so there is quite a difference.
That is another thing that can be a problem.
I agree to a lesser extent... I notice edge polishing much more in A/R lenses than in lenses without... especially recently when switching from a non-A/R coated pair to my new A/R coated pair that has been polished. It's not really bothersome to me, even with the high-index lenses that I wear... but it is something you notice as a little brighter, but I've only noticed it on pairs where there's a bit of edge poking out of the front and rear of the eyewires.
I polish nearly every set of lenses I make, and I can count on one hand how many A/R pairs have been returned in the past three years specifically because of the edge polish bothering the patient, so it isn't a common problem... but it does happen. As far as A/R making things "brighter," I know that we probably get about 3 or 4 returns a week between my stores because of patients who cannot adapt to the A/R, the most common response is that things do appear too bright, especially when driving at night.
Hey, PAW.
Tell the lady to stop cleaning her glasses. She won't be complaining of "too much light" anymore. Ha-ha.
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