Rx ballistic lenses?
- Thread starter Carol
- Start date
You know, that's something that's always nagged at me. I don't wear glasses -- but on the range, I wear approved ballistic safety glasses. But someone who does wear glasses just wears their regular prescription glasses. Which I know aren't "safety glass"...
I know, doesn't help your question. Haven't really known anyone who took it that far...
I know, doesn't help your question. Haven't really known anyone who took it that far...
Steve
Mostly Harmless
What are you using them for? Grappling/sports or someplace like a rifle range?
Rx prescription lenses can be purchased for not a lot of dough, for application in labs, on a range or other places where contact isn't really expected. If you're going to wear them on a basketball court or sparring or somewhere you expect contact, you're going to need something more.
My regular eye glasses have polycarbonate lenses. What (if any) difference is there between a regular polycarbonate prescription lens and a shooting-specific polycarbonate prescription lens?
Hopefully Dennis will chime in here, since it's sort of his area of expertise...
Hopefully Dennis will chime in here, since it's sort of his area of expertise...
http://en.wikipedia.org/wiki/Ballistic_eye_wear
As I understand the requirements; military ballistic lenses are made to withstand a higher velocity and slightly higher mass projectile. All spectacles are required to meet a minimum ANSI standard impact, but this is much lower than safety lens requirements. Safety lenses can be either glass or polymer with poly carbonate being far and away the most effective in stopping a projectile. I once had a very happy carpenter return his lenses for warranty replacement. He had been shot in the eye with a nail gun and the impact was right at the pupil. The poly carbonate lens had a nail imbedded dead center. It was so firmly imbedded that it could not be pulled out by hand but the tip of the nail had not penetrated the back surface of the lens.
Some considerations when selecting safety lenses in general. Many argue that glass is better optically though I believe production techniques have improved to the point where the difference is marginal. Glass is much heavier and therefor more fatiguing to wear. In addition; when glass is scratched, it will shatter along the scratch line, so glass safety lenses need to be replaced if there are any scratches. Plastic (poly carbonate) lenses are relatively soft and will scratch. This does not degrade their shatter resistance and modern scratch coats are significantly better in preventing scratches if you are careful. When viewed from the side; the eye is protected only for about 50% of its length by the boney rim. The front part of the eye is still completely exposed and projectiles can easily penetrate, this includes shards from the person firing next to you. The lens only protects from projectiles coming from the front. Side protectors are very important in preventing projectile injury from other directions. (In the first Arab- Israeli war 70% of the casualties were eye related in the highly mechanized combat environment).
Sport glasses have a sturdier construction to protect from differing mechanisms of injury than projectile. They typically have a more sturdy frame that wraps around somewhat so that impact from fingers, hands, baseballs and the like do not deform the frame and drive it into the eye. (I spent 3 hours one Sunday digging duck feathers out of a pilot who was hit in the face by a bird strike. The glasses didn't break but they were driven against his face so forcefully that the rims formed a perfect cookie cutter laceration around the eyelids).
A side note on shooting glasses that I learned from a local optician at the shooting range: If you are now at the age where bifocals are necessary and you site shoot. If you are having problems seeing the site in focus to target, try having them make what are called double D bifocal lenses on the top of the lens instead of the bottom. Have the focal point set for the distance from your eye to the far site in your shooting posture. This puts the site in perfect focus and is relatively easy to get used to. Some skilled opticians can also assist you by offsetting the center of the lens so that it lines up with your eye in shooting position (particularly in prone position rifle shooting). They can also assist by creating a clear center zone with a fogged periphery for your dominant eye so that you can easily pick the proper eye when siting. A sharp optician who knows shooting can be a real asset to a competitive shooter by making sure that the shooters glasses are set up for shooting position rather than for everyday use.
As I understand the requirements; military ballistic lenses are made to withstand a higher velocity and slightly higher mass projectile. All spectacles are required to meet a minimum ANSI standard impact, but this is much lower than safety lens requirements. Safety lenses can be either glass or polymer with poly carbonate being far and away the most effective in stopping a projectile. I once had a very happy carpenter return his lenses for warranty replacement. He had been shot in the eye with a nail gun and the impact was right at the pupil. The poly carbonate lens had a nail imbedded dead center. It was so firmly imbedded that it could not be pulled out by hand but the tip of the nail had not penetrated the back surface of the lens.
Some considerations when selecting safety lenses in general. Many argue that glass is better optically though I believe production techniques have improved to the point where the difference is marginal. Glass is much heavier and therefor more fatiguing to wear. In addition; when glass is scratched, it will shatter along the scratch line, so glass safety lenses need to be replaced if there are any scratches. Plastic (poly carbonate) lenses are relatively soft and will scratch. This does not degrade their shatter resistance and modern scratch coats are significantly better in preventing scratches if you are careful. When viewed from the side; the eye is protected only for about 50% of its length by the boney rim. The front part of the eye is still completely exposed and projectiles can easily penetrate, this includes shards from the person firing next to you. The lens only protects from projectiles coming from the front. Side protectors are very important in preventing projectile injury from other directions. (In the first Arab- Israeli war 70% of the casualties were eye related in the highly mechanized combat environment).
Sport glasses have a sturdier construction to protect from differing mechanisms of injury than projectile. They typically have a more sturdy frame that wraps around somewhat so that impact from fingers, hands, baseballs and the like do not deform the frame and drive it into the eye. (I spent 3 hours one Sunday digging duck feathers out of a pilot who was hit in the face by a bird strike. The glasses didn't break but they were driven against his face so forcefully that the rims formed a perfect cookie cutter laceration around the eyelids).
A side note on shooting glasses that I learned from a local optician at the shooting range: If you are now at the age where bifocals are necessary and you site shoot. If you are having problems seeing the site in focus to target, try having them make what are called double D bifocal lenses on the top of the lens instead of the bottom. Have the focal point set for the distance from your eye to the far site in your shooting posture. This puts the site in perfect focus and is relatively easy to get used to. Some skilled opticians can also assist you by offsetting the center of the lens so that it lines up with your eye in shooting position (particularly in prone position rifle shooting). They can also assist by creating a clear center zone with a fogged periphery for your dominant eye so that you can easily pick the proper eye when siting. A sharp optician who knows shooting can be a real asset to a competitive shooter by making sure that the shooters glasses are set up for shooting position rather than for everyday use.
OP
OP
Ideally I'm looking for safety glasses that I can wear around high-impact risks -- the target range and maintenance work in the park (mainly chainsaw) are my primary concern.
I do have a set of goggles that will fit over my regular glasses, but they are not particularly comfortable to wear for an extended period of time. I suppose I could find them to be more comfortable if the price for such glasses is outrageous, but I was curious if anyone has had a good experience wearing them
I do have a set of goggles that will fit over my regular glasses, but they are not particularly comfortable to wear for an extended period of time. I suppose I could find them to be more comfortable if the price for such glasses is outrageous, but I was curious if anyone has had a good experience wearing them
OP
OP
That is an interesting idea! Thank you!
ballen0351
Sr. Grandmaster
OP
OP
PERFECT! Thank you!
