Zeiss Individual vs. J&J Definity

**skirk1975** · 10-28-2005, 09:49 PM

This has probably been discussed before but I need a comparison of the Zeiss Individual vs. The J&J Definity. It is my understanding that although they are both classes as free form lenses, they are actually different. The Zeiss is a true freefrom and the J&J is not. Explain why ..............

please.:D

**For-Life** · 10-29-2005, 01:22 AM

They are exactly the same. They use the same technology

**Chris Ryser** · 10-29-2005, 04:55 AM

Originally Posted by For-Life

They are exactly the same. They use the same technology

Good For=Life, .............you are strating to catch on.........the all use the same tricks.....................but change the advertising.

**hcjilson** · 10-29-2005, 06:24 AM

Chris, its the advertising that sells the product. If the advertising sells my customer a better, more expensive product, then, I'm all for it!

**Chris Ryser** · 10-29-2005, 09:33 AM

Originally Posted by hcjilson

Chris, its the advertising that sells the product. If the advertising sells my customer a better, more expensive product, then, I'm all for it!

Harry, Of course you have a good point.............to almost being right.................

If your closest competitor does some smart advertising the other way round convincing YOUR customers that he has a good point.............would you not loose some business?

I believe you would customers are being convinced that product A is similar to product B but retails for a lot less.

In today's newpapers I saw the newest add by Ford promoting heavily the Focus, with all the fancy equipment of more expensive cars, trying to cash in on the economic squeeze plus the expensive gasoline.

Don't you think this policy is a smart move, diverting the customer interest to a smaller less expensive vehicle that will get you where you want to go for less than you could do in your Hummer where a tank full of gas is over a hundred dollars.

Dont you think that this way of thinking will eventually, or even very fast carry over into the optical business according to the economic foecast's ?

**Mikef** · 11-01-2005, 09:13 PM

Originally Posted by Chris Ryser

Harry, Of course you have a good point.............to almost being right.................

If your closest competitor does some smart advertising the other way round convincing YOUR customers that he has a good point.............would you not loose some business?

I believe you would customers are being convinced that product A is similar to product B but retails for a lot less.

In today's newpapers I saw the newest add by Ford promoting heavily the Focus, with all the fancy equipment of more expensive cars, trying to cash in on the economic squeeze plus the expensive gasoline.

Don't you think this policy is a smart move, diverting the customer interest to a smaller less expensive vehicle that will get you where you want to go for less than you could do in your Hummer where a tank full of gas is over a hundred dollars.

Dont you think that this way of thinking will eventually, or even very fast carry over into the optical business according to the economic foecast's ?

So Harry spends no money to advertise his lens the other guy does. Now the other guy has to charge more money for the no name lens.

If any Vendor advertises a product and you can sell it for more why is that bad. Why spend time and money to try to get a customer to spend less money so you can make less money! That makes not no sense in any business.

**QDO1** · 10-29-2005, 07:35 AM

Originally Posted by For-Life

They are exactly the same. They use the same technology

are they the same because they use the same technology? or the same because they are exactly the same? A D28 and C40 use the same technology, but clearly are not the same

**For-Life** · 10-29-2005, 09:34 AM

Originally Posted by QDO1

are they the same because they use the same technology? or the same because they are exactly the same? A D28 and C40 use the same technology, but clearly are not the same

IF they are actually different designs, the differences would be so small that one would not warrant any benefit over another.

**Chris Ryser** · 10-29-2005, 09:37 AM

Originally Posted by QDO1

are they the same because they use the same technology? or the same because they are exactly the same?

They are all the same technology .............but never exactly the same. They have to make a little change here and there to make the claim = NEW.

**Darryl Meister** · 10-29-2005, 11:33 AM

Originally Posted by For-Life and Chris

They are exactly the same. They use the same technology

That's like saying a Hummer is exactly the same thing as a Ford Contour, because they both use internal combustion engines. Not only that, but these two lens designs are fundamentally different in terms of both their performance and their implementation, even in the context of progressive lenses, in general.

For starters, Definity is currently a non-customized free-form progressive lens, which means that it really isn't much different from a semi-finished lens design.

Gradal Individual, on the other hand, is fully optimized for the wearer's prescription, pantoscopic tilt, vertex distance, PD, and reading distance. The physical design is changed, for instance, to account for the effects of the interaction between the prescription, oblique aberrations, and the optics of the progressive surface with the lenses in their position of wear. This ensures the widest fields of clear vision possible. The ECP is also provided with a small device to measure these position of wear parameters.

Additionally, the inset of the corridor and near zone of Gradal Individual is adjusted depending upon the reading distance, distance prescription (prism), and wearer's distance PD. Very few free-form designs currently do this, I might add. To the best of my knowledge, most -- including Definity -- use a fixed inset.

Gradal Individual is also available in two corridor lengths in order to allow fitting heights down to 15 mm. Definity has a single, relatively long corridor by today's standards.

Definity uses an ultra-soft lens design, similar in look and feel to a progressive lens like SOLA's XLGold. Gradal Individual has larger central viewing zones, and is very similar to Zeiss's Gradal Top progressive lens (at least until the prescription optimizations are applied).

Definity has split the progressive optics between the two surfaces for reasons that I won't get into (since it makes very little difference to the overall performance of the design). Gradal Individual uses a traditional toric back surface and a free-form progressive front surface. Gradal Individual is available in both 1.67 and 1.6 high-index.

But, yeah, other than that, they're both exactly the same. ;)

That said, now that Essilor owns the product, I would expect them to improve Definity's implementation if they continue to market it actively. So some of these statements may be subject to change eventually.

**sjthielen** · 10-29-2005, 11:51 AM

But it's easier to say that they are the same.;)

**Robert Martellaro** · 10-31-2005, 05:44 PM

Originally Posted by Darryl Meister

Gradal Individual uses a traditional toric back surface and a free-form progressive front surface.

The add is on the front surface? Are there any free-form PAL's with the full add on the back? Obviously it needs to be one that is free-form on the back surface. My understanding was that both sides of the Zeiss lens were surfaced and I assumed they were both direct surfaced or free-form. Looks like I need to take a closer look at how this new technology is implemented.

Regards,