Scratches on Lens have adverse affects on eyes?

[audelair]

I was just wondering whether minor scratches on glasses lenses have adverse affects on your eye/vision? i'm talking about light scratches that you can't notice when you are wearing them, but can see them slightly when examining the glasses.

how about with slightly deeper scratches?

Thank you very much.

[edKENdance]

I think this is a good question. I think any scratch that runs across the oc can cause problems.
As a lab tech, the one thing I find occasionally depressing is that a lens will be rejected for a small pit near the temporal portion of the lens yet progressive markings are etched much more closer to your oc and that's ok.

[audelair]

thanks for the reply.

when would you think a scratch would be problematic? deep scratches that you can easily see when held up against the light? or the very minor hairline scratches (from bad wiping), or the real light ones you can only see at an angle against a dark background?

for some reason, i don't really hear much about this being discussed. The reason i ask is that people tend to be bothered by scratches for cosmetic reason alone, since most light ones are not noticeable when actually wearing the glasses. i'm more concerned about the potential damage it would cause on your eye.

thanks again.

[edKENdance]

As a hyperope, the only time I'm bothered with a scratch is when it falls in my line of vision. I'm pretty sure that the scratches on my lenses would be unbearable to someone who is myopic. I don't think you'll find anyone on this forum who will say that a scratch can damage your eyes over time. Adaption is what the eyes do best. This is the reason why I was able to go uncorrected for more than 10 years.

[Cowboy]

Other than being an irritating nussance, scratches will not have adverse reaction to vision. Light transposing through the lens enters through the cornea, pupil, lens (internal) and finally resting upon the retina to stimulate the optic nerve to send the signals to the brain. Because most of the transposing light emminating throughout the lens is greater than the scratch, the scratch will not affect the bending of light rays overall, therefore no adverse reaction.

Does this help?





Cowboy

[Darryl Meister]

Scratches won't affect the power of the lens, but they can obscure vision to a certain degree. Even fine scratches can "scatter" light, like a dirty windshield in sunlight. Bigger scratches serve as an object for the eye and, when the pupil passes over them, can also obscure vision slightly because the scratch is defocused upon the retina.

Best regards,
Darryl

[harry a saake]

In actuality the bigger problem with scratches is it compromises the safety aspect of the lenses, even more so if the lens is glass. Most scratches are annoying i think more so then anything.

[Chris Ryser]

Make an artificial scratch on your camera lens, as tape a hair to the lens, have some ashes adhere to lens surface and take some pictures, first without, then with the objects stuck to the lens.

You will see that there is no difference

[Darryl Meister]

Stretch a piece of white thread over your pupil, at about the spectacle plane, and you'll see one effect. Drive around with a dirty windshield, particularly on a sunny day, and you'll see the other.

Best regards,
Darryl

[sandeepgoodbole]

audelair said:
I was just wondering whether minor scratches on glasses lenses have adverse affects on your eye/vision? i'm talking about light scratches that you can't notice when you are wearing them, but can see them slightly when examining the glasses.

how about with slightly deeper scratches?

Thank you very much.

If you can point out , you will save $$ in purchasing.
If you cannot hide , while saling lenses, you will loose $$.

Profit / Loss directly proportional to the deapth of the scratch.
and Near Vision Attended by the buyer.

[jediron1]

From Oklahoma State University:
"Your safety glasses are designed to protect you from accidental injury. They will not withstand repeated impact or abuse, however. Inspect them regularly for scratches, cracks or other wear and replace them if the are scratched, bent or uncomfortable. Scratches not only interfere with your ability to see what you're doing - a hazard in itself; they can also weaken the structure of the lens and its resistance to impact. Taking care of your glasses and, above all, using them, will help you "look" your best on the job".