So I have to ask, every one seems to love it, my self included, why is it not used more? It's better than poly in every way and only 10% thicker at most, usually it's not even noticeable. Yet I see so many doctors and opticians shrink from it when it's brought up. Any ideas why?
Surfaced Trivex lenses cost more than poly...not to mention poly stock lenses. probably just because of price.
The biggest drawback to it that I see is cost. It's usually a good deal more than Poly for the same product.
Perceived thickness is also an issue. Since it's 1.53 and Poly is 1.58, it's assumed that it will be thicker and thus heavier, despite the face that you need to be up near -10.00 before the thickness starts to become a factor, and it is the lightest weight material.
On another plus side, you can get it in Transitions in lens designs you can't get Poly in.
And the entire industry has had it pounded into their head that Poly is the greatest thing ever. Fortunately some of us have thick heads and it didn't pound all the way through.
There are rules. Knowing those are easy. There are exceptions to the rules. Knowing those are easy. Knowing when to use them is slightly less easy. There are exceptions to the exceptions. Knowing those is a little more tricky, and know when to use those is even more so. Our industry is FULL of all of the above.
Essilor has been pushing polycarb for so long that many ECP's people are brainwashed, or have just been intimidated into submission by Essilor. It has only been relatively recently that Essilor made Trivex available for their lenses, so maybe things will eventually change. I personally was involved in a brouhaha on this board about 10 years ago with an Essilor rep about this subject, and I was almost thrown off the board (I got a lot of interesting private messages on the subject).
Love it!Originally Posted by WFruit
And the entire industry has had it pounded into their head that Poly is the greatest thing ever. Fortunately some of us have thick heads and it didn't pound all the way through.
I figured cost could be part, but I get asked "Will my edger cut it?" on a regular basis. On the bright side if I know the person in question I get to let my snarky side out a little with the "Lets find out." Followed by the "smoke" when it cuts. I usual get them a drink if I pull the joke.
I would imagine it'd be hard to have time in the lab and not have a soft spot for Trivex. Still, some patients are very much out for the thinnest they can get on a budget. Plus poly gets a bum rap in some respects--(Uillean's profile has a blog link to a terrific DiSanto article on the powers necessary to manfiest abberation issues with poly. Got the chart printed for a cheat sheet at my dispense table. Thanks, U!)
Still, I've had all the stress marks and stress fractures I care to in this lifetime.
Many of us tend to oversimplify our pricing when it comes to upgrades---when we do it's easy for the trivex markup to exceed necessity on many lenses. In progressive lenses I find the difference pretty nominal and make sure to pass it through to the patient. In fact, when I think of all the work and hassle trivex saves me, I'm not averse to factoring that into Trivex' price.
Damn it! Why did you shatter the ideas I had due to exaggerated information on the abbe values?!?!? ;^)
I agree about the stress marks and cracks, and in drill mounds...poly is the devil.
So it does make progressives a bit better then?
Poly gets the rap it deserves. I just read the DiSanto article, and all that math is very nice and all, but I personally experienced horrendous chromatic aberration with polycarb in the reading area of a +4.50 -1.50@90 degrees, +2.00 add power progressive about 10 years ago. By horrendous, I mean very noticeable green and red fringing of text viewed with reading area of lens.Not to mention the distortion that was present in other areas, but not bad enough to color fringe. Problem was resolved by switching to 1.60.
Playing devils advocate here, but with a higher + rx and a 1.5 cyl is when I understand that poly becomes evil. Trust me though with a Rx like that I would say 1.6 min 1.67 is what I would give a person first.
In the pre digital age, trivex was almost an after thought when it came to availability, so nothing new was ever available in trivex (or so it seemed). In other words, it got frustrating to talk about trivex, then next thing you know, it isn't available with transitions or some other option. Also, Phoenix was terrible when it came to photochromics and yellowing.
AH HA!
I can see that. Does Have you, or any one still had the yellowing? I have a 2 year old pair that's fine, but wonder if I'm an out side stat.
Historically, there have been several issues, none of which was particularly easy to overlook:
1. Cost - even to this day, it's still more $ on average when compared against an equivalent poly product.
2. Availability - while it's better today than say 5 years back, it still lags behind poly in lens design options across many labs offerings.
3. Thicker - while it is lighter in SG than poly, it's thicker profile tends to negate much weight savings.
4. Yellowing - this appears to be largely solved now, but until fairly recently, these lenses often yellowed even worse than HI materials.
It's slowly making inroads nationwide, but I would guess that overall it will be hard pressed to compete with poly. I think it will take a new material entirely to really jump start interest in something beyond poly or 1.60. A few have shown promise (at least on paper), but have yet to make any sort of industry wide roll out of course.
I shy away if we are edging it because trivex is mean to edgers. personally, I've never had an issue with poly and I've had very few patient's who have had issues with poly so I take no issue selling it. if they do, i'll put them in something else dammit!!availability is also an issue.
"what i need is a strong drink and a peer group." ... Douglas Adams - Hitchikers Guide to the Galaxy
Not as easy to process on the lab side so powers are inconsistent on some Rxs which leads me to wonder if digital pals loose design details when processing.
On the finishing side causes extra wear and tear on equipment if you don't have the dedocated wheels for it.
On the plus side very nice clarity, tensile strength, and scratch resistant comparef to poly.
Poly and trivex both have a place in a dispensary, stock lenses tend to mitigate the negatives better for trivex.
Abbe tends to be less an issue in SV compared to MF, but a shorter corridor design with no prism thinning helps in poly.
I haven't had to deal with the yellowing problem yet, but trivex is a big pain to polish and groove on rimless/semi-rimless mounts.
I would propose that it has more to do with how one presents material benefits. I don't see a big difference in the price point when comparing trivex with polycarb, it is No 2 lens material behind Asph HI-1.60 in my dispensary. As to restrictions, you will find that their are limitations in one form or another with any material. I try to limit my patients lens options dependent upon, frame choice, optimum acuity/performance of RX, decentration, and past history.
I didn't attend the funeral, but I sent a nice letter saying I approved of it. Mark Twain
I love Trivex. It doesn't starburst fracture like poly when you drill it. Higher abbe value then poly. Tougher then poly (tensile strength). A little more expensive? Bah I say! It's not a huge amount like going from cr-39 to high index. Tougher on your edger you say? Sure, its a tougher material then poly. The life of your grinding wheel may shorten a bit if your cutting Trivex all day long, but its not like cutting 1.74. Your wheels will need to be changed if you cut plastic and poly eventually. I haven't really had a smoking problem edging trivex, but the Topcon I use has a trivex setting. It may take the speed and pressure down so it doesn't grind as hard. Iv'e read a few articles saying that the industry is trying to change the gold standard for safety glasses from poly to Trivex. To do that they need only to lower the price a small amount. After that, poly will go the way of glass.
What in the ....... Howdid this end up in my favorite places list?
http://www.2020mag.com/l-and-t/41604/
Barry did you write this? You sly fox......Fanstastic!
Last edited by chaoticneutral; 10-27-2014 at 12:58 PM.
Trivex is my friend; we do 96% and the rest is 1.67 because we do 70% drill mounts and we love to edge it! We are built to run trivex and so is our surfacing lab. We get high plus and minus re's that are the lightest possible with the best optics; that is what our clients want and expect!
Get your edger fixed if you cannot edge it.
Everyone here is piecing together all the correct reasons for it's not so full embrace, however it will happen in due time. It is a fantastic material that provides incredible optics, durability and tensile strength, far superior to poly.
Since E mostly controls the marketplace and is so committed to their deep investment and marketing spin on poly, they can't back out now. Although interesting enough up here in Canada they are expanding their availability on Trivex on both surfaced and stock lenses more and more.
To those ECP's that complain about the minimal cost difference of a few bucks, suck it up and dispense with quality and assurance. Your redo percentage due to poly's crankiness will drop substantially and actually provide better profit and loyal patient satisfaction.
Agreed, I have had more WOW's with trivex than anything other than 1.67 and that's for the thinness of it.
I'm amazed how many people love it here and glad to know I'm not crazy for holding it in such high regard. Thank you all again!
I personally think that lack of progressive thinking towards trivex leads people to not use it. Certain stuck in their ways opticians just don't want to believe that anything new can be good.
The majority of opticians (not all) are creatures of habit, not progressive thinkers that embrace technology. They are more price driven and concerned about how much they will make on each individual sale rather than upselling and providing the absolute best products on the market to their customers. Stepping over a quarter to pick up a nickel will never advance one's retail practice.
So if it's a mix of both lack of experience and price sensitivity seems like an easy fix. I know most of the time lab is not that much more, far less than 1.60, and stock might as well be the same. Though when I worked as a CSR at a lens distribution I would get chewed out for $.60 so there is that.
Sort of OT, but, a question in re: Trivex. What are other opti's experience with its' scratch resistance? I work in one of those rare offices to have embraced Trivex, and it's easily 90% of our jobs. But since the switch, I've also tracked a significant uptick in scratch warranty use since the days of a CR-39/Poly split (and CR is still our least-scratched material). Should I be looking at our AR coatings, or is there another culprit?
Are the scratches deep enough to penetrate the coatings? If not, I think you're on the right track. I'd suspect other variables before I suspected the trivex. (And I'm not above doing the sound test on lenses to make sure they're not poly when I didn't order poly. Haven't caught many mistakes this way, but I've caught a couple over the years.)
90% trivex! I thought I was hard core with my 50-55%!
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