Blue Line in Vision

[GrahamEye]

I have two patients:

One is wearing a brown metal frame, Varilux prog poly, unpolished edges, with no AR.
Other wearing a zyl frame (brown top with clear color bottom), TruClearSD poly prog, unpolished edges, with a VisoXC AR.

Both are stating that when they are driving that they see a "blue line" in their vision on signs, road, and fences. They only see this line when they are driving and nowhere else.
Time of day does not see to be a factor and not certain if cloud coverage is a figured into this. I do not know about their vehicles or window tints, but highly unlikely they have a specialty tint or coloring.

Have any of you come across this? If so, what did you find was the cause?

[Hayde]

It sure sounds like chromatic aberration (perhaps augmented by refraction of the windshields?) I'd be interested to know the prescriptions before buying a raffle ticket, but I only see one common strong denominator between the two so far...good old polycarb.


An inexpensive experiment would be to edge some uncoated CR39 SVs for them and see if they can reproduce the problem.

[Uncle Fester]

If I throw this thread against the wall will it stick???

http://www.optiboard.com/forums/show...ght=color+lens

[mervinek]

If it was chromatic abberation from the poly, wouldn't it be seen at other times too? I've never heard of a patient that had a problem with poly only in certain conditions. I had only a few patients with poly issues and they pretty much had it all the time, not just when driving. I honestly don't run into poly issues often, so I don't have much experience with it.

[Hayde]

If it was chromatic abberation from the poly, wouldn't it be seen at other times too? I've never heard of a patient that had a problem with poly only in certain conditions. I had only a few patients with poly issues and they pretty much had it all the time, not just when driving. I honestly don't run into poly issues often, so I don't have much experience with it.

My experience would be consistent with yours, merv. My tentative theory was that something about the car interior mediums is compounding the effect.

(For an optically entertaining experience, slowly move yourself across the car seat fixing head position and watch all the waves in your front windshield!)

[Robert Martellaro]

I have two patients:

One is wearing a brown metal frame, Varilux prog poly, unpolished edges, with no AR.
Other wearing a zyl frame (brown top with clear color bottom), TruClearSD poly prog, unpolished edges, with a VisoXC AR.

Both are stating that when they are driving that they see a "blue line" in their vision on signs, road, and fences. They only see this line when they are driving and nowhere else.
Time of day does not see to be a factor and not certain if cloud coverage is a figured into this. I do not know about their vehicles or window tints, but highly unlikely they have a specialty tint or coloring.

Have any of you come across this? If so, what did you find was the cause?

It has been seen rarely, once in my career, once mentioned in Dr. Sheedy's old newsletter (no resolution), and here on Optiboard once or twice, again without a clear indication of the cause. My client was a moderate myope, approx. -4 D, SV I believe. She only saw it at optical infinity, looking out the window or outside, essentially under high contrast conditions. Lenses were 1.67, with at most, a moderate change in Rx I believe. Vertical OCs were probably about 5mm below.

Thinking Chromatic Aberration, I raised the OCs closer to the primary gaze, and used a higher Abbe material, probably Spectralite. Symptoms were reduced significantly, but still present. I couldn't explain it beyond my explanation of CA and its effects on vision. I never saw her again.

My present thinking is that it's due to an interaction between spectacle lens dispersion and our eye's own CA. I wouldn't rule out the Rx as a contributor, or as the primary cause. For your PAL client, I would suggest removing the prism thinning, if any, switch to a high Abbe material, and confirm the Rx. Because lightning has struck twice, confirm that the exam room and instruments are calibrated and set up properly.

Hope this helps,

Robert Martellaro

[Tallboy]

Chromatic abberation can absolutely seem more prominent in some situations over others, such as looking at black letters letters on a a white background. I'm not certain what the cause of the blue line is in this situation, but I'd redo one of them in either CR or 1.60 and see if it helped.

[lensmanmd]

Horizontal or vertical lines?

[Robert Martellaro]

Horizontal or vertical lines?

Mine, and the others, were horizontal, near the primary gaze.

[lensmanmd]

Mine, and the others, were horizontal, near the primary gaze.

Thanks. So here is the rub. More likely to do with the vehicle and windshield design than lens material, not to completely eliminate the lens, however. I have some of the same issues when driving my SUV. No issues at all driving the wife's sedan.

The windshield on my SUV is tall and quite slanted. My dash is quite deep. This combination creates quite a reflection right smack dab in my central vision. During the day, I wear polarized, so it really doesn't bother me. Low light, however, I get some reflections every now and then that does bother me. Same glasses, different car, no issues. Can't say its the lens material.

I'm not saying that this is the problem, but more likely a contributing factor. At night, if the dash has LED lighting, this may also contribute. Just something else to think about before blaming it all on CA.

[Lelarep]

I'm also betting its an interaction between the lens and the windows in the car. Remember, windows in cars aren't clear, they have a solar tint to them, which is usually in the green-blue spectrum. I'm betting that is where the blue color is coming from.

[Robert Martellaro]

I'm also betting its an interaction between the lens and the windows in the car. Remember, windows in cars aren't clear, they have a solar tint to them, which is usually in the green-blue spectrum. I'm betting that is where the blue color is coming from.

Are you saying that they're confusing the shade band at the top of the windshield with a defect in their ophthalmic lenses? Lordy, I thought I had heard it all.

https://www.safelite.com/windshield-...y/visor-strips

Best regards,

Robert Martellaro

[lensmanmd]

Not the visor strip, but a reflection of the dash on the windshield. Some vehicles are worse than others.

[andshewas]

This guess may be a stretch, but it sounds like a symptom of crazing. I'm not sure what the optics of a crazed hard coat look like, but my crazed Crizal Sapphire lenses had a horizontal blue line at eye level when driving at night and approaching signs or oncoming headlights.

Barring any lens defects, I would agree that it's probably a windshield issue.

[GrahamEye]

Update:
The first patient wearing the brown metal frame, TruClear (not Varilux as I thought it was) prog poly, unpolished edges, with no AR came back in today.
They were still was seeing the "blue line", outside only, during the daytime, and off of static objects. Said the line showed off of car wheels, the edges of buildings, and the power lines.
I could not see the line while I had the glasses on. I could see, when looking at the patient's profile of the glasses, a definite rainbow effect going through the lens, but only at that side angle and not straight on.
Other note: patient's previous BC as a 4.5 and the new BC is a 6.5.
I am changing the BC to match previous style and the material to CR-39.
Will update once the new pair arrives and the patient tries them out.

Second patient is being resistant to help and just wants a refund. Not likely to track down that solution at the moment.

[Lelarep]

Very interesting, its happening even just standing outside, must be some form of chromatic aberration.

[GrahamEye]

Update:
Second patient returned glasses and refused any assistance to help identify the issue.

1st patient:
After changing to CR-39 and changing the BC to 4.5 from 6.5, they no longer sees the "blue line".
It could be possible that the BC may have had more of an impact than the poly.
End result for this patient is that they are now happy with their glasses and RX acuity.

[AngeHamm]

Update:
Second patient returned glasses and refused any assistance to help identify the issue.

1st patient:
After changing to CR-39 and changing the BC to 4.5 from 6.5, they no longer sees the "blue line".
It could be possible that the BC may have had more of an impact than the poly.
End result for this patient is that they are now happy with their glasses and RX acuity.

Sounds like your practice is better off without that second patient.

[Lelarep]

Sounds like your practice is better off without that second patient.

No doubt there.