Coo-Coo for Contact Lenses!

[Andara Bledin]

(As for why glass, my experience with plastic has been that even with "scratch resistant" coating, just from going about my normal day they acquire scratches all too quickly for my tastes.)

Either you are super tough on your glasses, or you've gotten some really crappy plastics.

My ex is accident-prone, a live-steel-fighting rennie, and when he cleans his, he uses anything that's to hand, including cheap scratchy fabric used to cover the haybales at faire and his survive longer than the prescription. *shrug*

^-.-^

[Shalom]

Depends on the plastic.

I have to use CR-39, which is the oldest (and thickest) plastic on the market, because every time I've tried thinner lenses I couldn't see through them, due to the chromatic aberration. They just wouldn't focus anywhere except dead center of the lens. If I moved my eyes left or right without turning my head, it fuzzed out on me. This is fine if you're an owl, but I do have the ability to move my eyes in various directions (OK, except up and to the left), and once in a while have difficulty turning my head back and forth (d/t chronic neck/back problems), so this is a non-starter for me.

(First the optician tried to tell me the opthalmologist had written the wrong prescription; then he told me not to look out of the outer parts of the lens, and blacked them out with marker. Then he bent the frame in a V, so far that part of the nosepiece actually snapped. None of this improved the vision through them. He finally admitted that polycarbonate gets iffy once you get past -8 diopters (I'm around -8.75/-9.5). I asked him what to do next, and he told me to turn my head to look at things. I told him that wouldn't cut it, and I wanted the lenses remade on the older low-index plastic. He eventually did that, but wouldn't refund me the difference in price between the polycarb and the (cheaper) CR-39. It goes without saying that this was the last time I ever used that particular optician.)

And yes, I do get the anti-scratch coating, and yes, they do get scratched up regardless. You should see what mine look like right now: it's amazing I can see anything through them at all. Of course I'm two years overdue for new glasses, and these lenses have been cut down twice from previous frames and are therefore something like 8-10 years old, but even so.

[Broomjockey]

are therefore something like 8-10 years old, but even so.

Er, no, not even so. Taking the low end of 8 years puts those at pretty darned good.

[Camry178]

Shalom, have you ever tried a high-index plastic like 1.67 or 1.74? Polycarbonate starts to suck once you go higher than 6 diopters. You should try going somewhere with a money-back guarantee in case you still can't adjust to them.

[JuniorMintz]

Shalom, out of curiousity do you wear single vision or multifocals (lined or nolined)?

Also, what is your approximate Rx?

For those who don't already know, here's a quick breakdown of lens materials:

PLASTICS

CR-39/Standard Plastic- The most basic of materials. Thicker than all other plastics. Can be ordered with or without a scratch coat. Good optical clarity. Will work for just about everyone, even if the end result is very thick you should still be able to see out of them.

Polycarbonate- AKA "safety glass". Scratch resistant. Polycarb is considered a mid-index plastic, meaning it's thinner than CR-39 but thicker than high index. Impact resistant. Optical clarity ok, but not as good as CR-39 or high index. Despite the reduced optics, it's still recommended (in some cases, even required) for the following situations: work/safety glasses, sports or bike goggles, children's glasses, semi-rimless frames, and for the protection of those patients who have only one eye with functioning vision. Usually NOT recommended for patients with high amounts of astigmatism, if it can be avoided. (I'm very astigmatic and I'm highly sensitive to polycarbonate lenses).

Trivex- a mid index, of higher quality (and price) than polycarbonate. Much better clarity than polycarbonate. Required for use in completely rimless glasses (drill mounts), because they can be drilled without cracking. Scratch resistant. Ok for astigmatics.

High Index- comes in many indexes, most common is 1.60. Thinnest lenses you can get. Scratch resistant. Excellent optics. *NOT* impact resistant/drillable. Ok for astigmatics.

For All Plastic Lenses
In my experiences, a patient who is truely careful (or lucky) will have their lenses last for about 4 or 5 years. This is under the best of circumstances (either that, or they are rarely used!). Most plastic lenses will start to come apart after 1-3 years, depending on how they've been handled. This is why most insurance plans have a replacement frequency of 1 year if it's a good plan, 2 if it's not so good (but still better than nothing, LOL)

GLASS

Glass lenses come in high index as well as standard plastic. Clarity is very good. Can NOT be used for any type of rimless frame. Overall, the most resistant to scratches tat you can get, but if the lens happens to fall out, more than likely they will shatter, whereas plastics will scratch but at least stay intact. Only about 5 percent of my patients (if that) ask for glass, because those mofos are HEAVY. When placing orders, all patients are given plastic unless glass is specifically requested.

Glass lenses can last for many years, so long as they don't accidentally shatter somewhere along the line.

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For the record, my Rx is single vision, about -0.50/-0.75 distance and -1.75 in astigmatism. I always order standard plastic, because my Rx is not severe enough for a high index and there's no frickin' way I'm doing poly because of my astigmatism.

I ALWAYS get an anti-reflective coating as well, because I am already light sensitive (light blue eyes and permanently large pupils). Astigmatism makes light sensitivity even *worse*. ARC is high maintenance, so I don't suggest it for those who are super super rough on their lenses-the payoff isn't worth the risk. For those who struggle with night driving or eye fatigue due to florescent lights or computer screens, it's a life saver.

Sorry so long. I can't believe I wrote this much technical info when I'm off the clock. I'm a rambler, LOL.

I'd be happy to answer any more questions you guys may have, if I haven't bored you to death already.

[Andara Bledin]

Overall, the most resistant to scratches tat you can get, but if the lens happens to fall out, more than likely they will shatter, whereas plastics will scratch but at least stay intact. Only about 5 percent of my patients (if that) ask for glass, because those mofos are HEAVY.

My ex must have been blessed when he still had his glass lenses.

He put them through hell and back; dropping them, having one lens fall out regularly because of a cheap pair of frames, and they were in an accident where the car wend end over end for nearly a full rotation (and landed on the tires after bouncing off the rear fender) where they ended up somewhere in the back after flying off his face. Nary a scratch.

He switched to plastic after a direct strike to the face from a bokken (bokuto, wooden practice sword) cracked one lens into several pieces. The blessing still held, however, and the worst he got for it was an impressive black eye (the edges of the lens had dug into the skin all around), no cuts, and a rather heated tongue-lashing from our guild mistress for his not having plastic lenses to begin with. The person behind the strike also got a severe reprimand for the safety violation, too.

^-.-^