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Hi everyone!
How do you explain the difference between high index and polycarbonate to your patients? I know that high index is thinner, but is that the only benefit to the patient?
Sorry if this is a repetitive question, but I have searched the other posts and I can't find anything specific as far as what to say to patients.
Thanks so much for all of your help!
-Whitney
I always explain to people that light travels faster in Hi Index vs. poly, thus providing clear vision. Itell them that since poly is softer it is more impact resistant, but light travels slower causing more distortion. I hope this helps.:)
You might also mention that poly distorts colors and other images more.
Poly scratches much more easily.
Poly is easily eaten by chemicals such as acetone.
The only reasons to use poly are: It's light weight, and to protect the dispenser from lawyers.
Chip
Than why do so many people prefer poly? That's amazing! GREAT tips! Thanks, Chip and Mel!
1) It's cheaper to make, and is marked up considerably making a good profit.
2) Impact resistant.
3) Most places sell it because of those reasons.
I personally sell it only to people who are wearing it already, and to children. Other than that, I use CR 39, high index or trivex.
Polycarb has to be cured for a year. If not it will develop stress cracks. Being the demand is so high, they are not curing them as long, so more cracks.
I do not wear it because with my whacked out prescription i will go batty. Hi index for me!
That's my take on it.
Quote:
Originally Posted by whitneyd74
Probably because the have never worn a CR-39 or crown glass lens.
Actually, it travels slower, which is why you don't need as much of it to bend light the same amount.Quote:
Originally Posted by melthemadhatter
Also, what high index do we mean? Some high indexes are higher that other high indexes. Do you think of 1.55/1,56/1.58 as HI ? Or do we start at 1.6, 1.67, and 1.70? Or do we need 1.74 to be truly "high" index?
Quote:
Originally Posted by finefocus
Indeed. I stand corrected! I was thinking one thing, but typing another. I must have been thinking of Spectralite..:o
I know the chain I used to work for would push poly more than any other lens type.
When the big chains push something I suppose it probably affects the consumers perceptions. If a consumer walks into a big chain and then writes them an estimate with the "best" lens material available and they do it for poly (assuming they trust the mctician working there) that consumer now thinks poly is the best available material.
now that I have escaped the chains... of the chains... I see that poly is really only good for its impact resistance when you dont (for some reason) want to use trivex.
You could tell them it's cheap because there was so much of it left over from ship's hole liners after WWII. They had to do something with it.
In fact if it's so cheap why do sheets of it cost more than sheets of plexiglass at the Home Depot?
I recommend poly specifically for weight and safety. Hi index for cosmetic reasons or for better visual acuity. I try to keep it simple.
Poly distorts colors more than 1.67?? I thought they were pretty much the same.Quote:
Originally Posted by chip anderson
Poly doesn't scratch, the hard-coat scratches. The scratch-resistance is only as good as the hard-coat. There are good and bad. Same with high-index. I also needs a hard-coat. Every type lens needs a hard-coat except CR and glass.
The other reasons to use poly are low cost, thin centers are available, relatively high index, and to prevent chipping and flaking in rimless.
I know lots of people are down on poly and I will admit that it is never THE BEST choice. But it is very often the best compromise lens in terms of light weight, thinness, toughness, and availability.
Poly do scratch, dat why it need hard coat. Duh.
Un coated you finger nail or even your finger pad enough to scratch it.
Wow chip, you really do come off as a grumpy old man sometimes... LOL. :p
Anyhoo, we really dont have very many problems with poly compared to what I've heard in the past, like many many moons ago when poly was considered not as clear as plastic. I guess in a high Rx comparison, hi index would be a little clearer, maybe little less distortion, but we still use poly quite often. These days especially, I find our patients dont want to spend much over what their insurance will cover for them, so poly is a great bang for your buck option. We always use poly for children, safety glasses and for our monocular pt's too. We consider 1.56 and 1.60 mi-index's and 1.67 and 1.74 are hi index. I guess to summarize I would say poly is thin, lightweight and impact resistant... where hi index can be even thinner and great for hi Rx's.
My suggestion as a former really high myope is to scrap the 1.67 and 1.74 index and use the 1.70. Better ABBE means clearer vision.Quote:
Originally Posted by OptiChick21
Dang, check out this link:
http://www.nationmaster.com/encyclop...orrective-lens
Pretty awesome.
Quote:
Originally Posted by chip anderson
Chemicals will not damage poly if properly protected. The hard coat protects the surfaces there is only the un protected edge that can start a chain reaction.
However there are now easy to apply edge protection coatings that will prevent any damage.
Hi Whitney...Quote:
Originally Posted by whitneyd74
The way I explain it to the pt depends on what their needs are...
For example, If the RX is SV and it's a child or any pt with a balance RX, I'll go over the benefits as far as impact-resistance, and UV protection...
If the RX is for a BF, TF, or PAL I will recommend 1.60, or 1.70 (depending on the RX, when a hi-index material is needed)...I don't usually give a choice of poly for these pts (unless it's a balance RX, or it's a money issue for the pt)...from my experience, I will rarely have trouble with material non-adapts with a 1.60 or a 1.70. *I also use 1.60 for drilled frames, regardless of the RX..I like the results better.
As far as a real explanation for the pt...I just tell them as much as I think they want to know...
I've had pts that say...'don't tell me, just do it, your the Optician, not me!'...for them, I just tell them their cost and go with it! :)
I've had others that come in and say..'what's the difference?'...for them I tell them about ABBE values and my personal experiences with the different types of lens materials they are considering and why I would (or wouldn't) use certain materials.
Best advice I can give, is get comfortable with the reasons YOU like the lens materials and what their benefits are for different applications...and share that with your patients...some will want lots of explanation, others won't want much...either way if you are familiar with the benefits of the lenses your office offers to patients, your patients will be comfortable with your suggestions and explanations.
Hope this helps a little..:)
One thing I hear a lot that drives me batty is the idea that High Index is "thinner and lighter" than poly.
I think it may be true in circumstances where mass removal via thinning and/or asphericity outweighs higer indices' higher specific gravities.
But, yeah, a cubic cm. of polycarbonate will be lighter than a cubic cm. of MR7, e.g.
Pretty solid information, although they got a little lost with...Quote:
Originally Posted by drk
"This qualification is necessary since best-form spherics are always better than aspherics for an ophthalmic lens application".
Right. In many cases the implication is that super high index is lighter in weight than mid and high index. This is simply not true (see below).Quote:
Originally Posted by EyeFitWell
Using typical lens sizes and similar surface designs, Poly is the lightweight king up to the low to mid-teens (except for Trivex, which is lighter than all lens materials below about 9 D).Quote:
Originally Posted by drk
I know some people have problems with poly but I think it's very few. I have right now both cr 39 and poly eyeglasses and I see just as well with the poly as I do the cr 39. My husband's eyeglasses are polycarb, also. It's not the perfect material for everything but it works well a lot of the time and is cheap which patients like.
Everyone keeps talking about how Poly is cheap. The labs I use charge a little more for Poly than CR-39. Is there something I don't know?
Chip
Poly is less expensive than everything except CR-39.Quote:
Originally Posted by chip anderson
It doesn't chip, it's thin, it's lightweight, it's impact resistant and it costs only $30 more (in our shop). That is value that 85% of you patients will want. Try selling it. Your patients will appreciate getting lenses that aren't thicker that what they get at Wal-Mart.
Or you could ask your clients "Would you like the absolutely cheapest lens that I can get?" You might be surprised at how many will say no.
Yes, it costs more then plastic but less then anything else. It's thin, it's light, it's safe. I can't remember the last time I've had a patient have a problem with vision through it.Quote:
Originally Posted by chip anderson
Of course, I don't recommend it to everyone. I recommend higher index lenses for stronger prescriptions, high index or Trivex for drills. I recommend regular plastic,too, if the rx is low, less then -2.00 or so.
I'm getting more and more away from poly. The responces I've got from Trivex are actually surprising to me. The most common responce is " things seem brighter" or "less dull". I wish ( and know some day will happen) more designs of lenses will be available in Trivex.
It's not for every Rx, and it's not available in some designs we select for patients, I hope to see it's usage and availability increase soon....
*(this will only happen if the "evil empire" acquires the patent on Trivex...)