The Re-Birth of the Bifocal via FreeForm

[Barry Santini]

I think its time to let Bifocals enjoy the say correction-enhancing benefits that Profressives and SV lenses enjoy from iterated, personilized, Free form lenses.

Just start with the Bifocal style and material of your choice, and *digitize* it.

What say you, Optiboarders? Can the "lowly" bifocal be reborn in the digital age?

Barry

[drk]

What would a backside FT 28 look like??

[Chris Ryser]

As bifocals would be fused on the backside where you surface they would look like "easter eggs" and out of shape. :bbg:

[HarryChiling]

I think its time to let Bifocals enjoy the say correction-enhancing benefits that Profressives and SV lenses enjoy from iterated, personilized, Free form lenses.

Just start with the Bifocal style and material of your choice, and *digitize* it.

What say you, Optiboarders? Can the "lowly" bifocal be reborn in the digital age?

Barry

Barry your the man. How about someone block it upside down and FF a progressive onto the back for an Occupational, or utilize differing seg powers and back side blended segs to create a wider variety of trifocal that 50/50, 60/40 or Double segment lenses with more variety than just 100% or 60% add up top. I think their is potential for improvement to a bifocal or any style lens with FF.

[Jacqui]

Why not just put an atoric curve on the minus side of a D-28 or 35 or exec or...or...

This is no big deal, current software allows it.

[Barry Santini]

Why not just put an atoric curve on the minus side of a D-28 or 35 or exec or...or...

This is no big deal, current software allows it.

Jacqui. *this* is what I had in mind....

Barry

[HarryChiling]

Jacqui. *this* is what I had in mind....

Barry

This is what they should be doing with all progressives IMO with a digital upcharge, instead of createing or calling it a whole new lens.

[Jacqui]

This is what they should be doing with all progressives IMO with a digital upcharge, instead of createing or calling it a whole new lens.

I think they should do it with almost all lenses. :D

[Craig]

I think its time to let Bifocals enjoy the say correction-enhancing benefits that Profressives and SV lenses enjoy from iterated, personilized, Free form lenses.

Just start with the Bifocal style and material of your choice, and *digitize* it.

What say you, Optiboarders? Can the "lowly" bifocal be reborn in the digital age?

Barry

You are on the right track again!

I have thought this was a natural extension of free-form and the bi-focal zone is almost invisible from the front and no shelf for coating issues. THis would allow for a "digitial dual zone lens" where you could set it up on an 8 base wrap sunglass with an extra drop of 5mm from the OC to the seg ht. This would be done with compensated optics and prism thinning if necessary.

There is a huge need for a high tech free form dual zone lens. The new NXT polarized is only available in Semi finished blanks and any bifocal will have to be done with free form technology anyway.

I presented this over the summer and the legal patent issue dealings along with Essilor rumors have certainly slowed new projects.

I am going to follow up again today on this project.

Craig

[Robert Martellaro]

I think its time to let Bifocals enjoy the say correction-enhancing benefits that Profressives and SV lenses enjoy from iterated, personilized, Free form lenses.

Just start with the Bifocal style and material of your choice, and *digitize* it.

What say you, Optiboarders? Can the "lowly" bifocal be reborn in the digital age?

Barry

Should be doable right now in cr39 because the BCs are available, problematic for the mid and hi-index, where additional BCs will have to be manufactured, an expensive proposition. I'd probably want an aspheric/flatter BC, which I asume would make the software more complex and expensive, and further limit the material choices. Yes, I want it all.

Didn't Optical dynamics have an atoric segmented? If I remember correctly, the cyl topped out at two diopters, making me wonder what was the point?

Regardless, I could easily fit five to ten a month if I could get it in Trivex and 1.70 or 1.60.

[Jacqui]

Should be doable right now in cr39 because the BCs are available, problematic for the mid and hi-index, where additional BCs will have to be manufactured, an expensive proposition. I'd probably want an aspheric/flatter BC, which I asume would make the software more complex and expensive, and further limit the material choices. Yes, I want it all.

Didn't Optical dynamics have an atoric segmented? If I remember correctly, the cyl topped out at two diopters, making me wonder what was the point?

Regardless, I could easily fit five to ten a month if I could get it in Trivex and 1.70 or 1.60.

We're working on it, Robert. We have software written for CR-39, with Trivex and 1.60 next. 1.67, 1.70 and 1.74 will be later.

SV blanks in one diopter base curve steps are avilable in all materials, so this is no problem.

[Newyorkoptician]

As bifocals would be fused on the backside where you surface they would look like "easter eggs" and out of shape. :bbg:

Chris if memory serves me correctly didn't the ultex series come in a few that were back side?

[Newyorkoptician]

Jacqui. *this* is what I had in mind....

Barry

I agree with Robert. I thought a few years ago there was all this talk about atoric's. I would think that is basically the same principle all you would have to do is adapt it for a st.top 28 or 35 which should not be that hard since most of the work has been done in the atoric design.

[chip anderson]

If the bifocal were fused on the backside I think the patient would have less trouble with glare off the top, especially on sunglasess. The lens would also not be prone to scratch at the topmost portion Most used) of the bifocal In fact if it were fused with a higher index plastic as the glass lenses were, there would be no need for a seam or glare. There are other plastics out there with varieng indices and obviously the ones we have can be modified to change the indice.
How come no one is doing any research into this?

Chip

[rinselberg]

If the bifocal were fused on the backside I think the patient would have less trouble with glare off the top, especially on sunglasess. The lens would also not be prone to scratch at the topmost portion Most used) of the bifocal In fact if it were fused with a higher index plastic as the glass lenses were, there would be no need for a seam or glare. There are other plastics out there with varieng indices and obviously the ones we have can be modified to change the indice.

How come no one is doing any research into this?

Anyone who has been following this thread may also be interested in the technology that has been used in the new atLast! multifocal lens. I'm not endorsing the atLast! lens. But if you haven't already, read about the technology:

http://www.atlastlens.com/pages/composite.html

[chip anderson]

Riselberg:

Looks a little like some of the fused segment bifocal contact lenses from back in the PMMA days. Odd it's taking ophthalmic lenses so long to notice the technology.

Chip

[Jacqui]

If the bifocal were fused on the backside I think the patient would have less trouble with glare off the top, especially on sunglasess. The lens would also not be prone to scratch at the topmost portion Most used) of the bifocal In fact if it were fused with a higher index plastic as the glass lenses were, there would be no need for a seam or glare. There are other plastics out there with varieng indices and obviously the ones we have can be modified to change the indice.
How come no one is doing any research into this?

Chip

Probably is research going on, we just don't hear about it.

[JerryR]

Pixel Optics with their atLast lens has has 2 different indices infused together, Trivex and 1.67.

[Robert Martellaro]

We're working on it, Robert. We have software written for CR-39, with Trivex and 1.60 next. 1.67, 1.70 and 1.74 will be later.

Cool.

SV blanks in one diopter base curve steps are avilable in all materials, so this is no problem.

Now I'm confused. I thought we were talking about an atoric back surface using free-form on a semi-finished one-piece segmented. How can you make a ST with free-form? As doctor K said, what would it look like? An indention on minus spheres and a bump on the plus powers? How would the Add power blend into the carrier? Something like a younger blended?

If the bifocal were fused on the backside I think the patient would have less trouble with glare off the top, especially on sunglasess. The lens would also not be prone to scratch at the topmost portion Most used) of the bifocal In fact if it were fused with a higher index plastic as the glass lenses were, there would be no need for a seam or glare. There are other plastics out there with varieng indices and obviously the ones we have can be modified to change the indice.
How come no one is doing any research into this?

Chip

Wouldn't it be on the front? I like the idea of a fused plastic- there would be no ledge for dirt to collect and no coating runs. Sounds expensive though. Maybe combined with an atoric back there might be a market. There might be a problem with the diminishing market demand for semented multifocals though. It seems that most of the R&D dollars are going towards progressives, and rightly so considering their popularity. OTOH, vinyl (records) are making a comeback, why not segmented?

Anyone who has been following this thread may also be interested in the technology that has been used in the new atLast! multifocal lens. I'm not endorsing the atLast! lens. But if you haven't already, read about the technology:

http://www.atlastlens.com/pages/composite.html

It looks like a round Smart Seg. If true, no thanks. Regardless, thanks for the heads up.

[Jacqui]

Robert:

I was talking about freeform and SV. You can at times (and places) get segmented bi's in 1 diopter steps, if you are lucky.

[Lee Prewitt]

You are on the right track again!

I have thought this was a natural extension of free-form and the bi-focal zone is almost invisible from the front and no shelf for coating issues. THis would allow for a "digitial dual zone lens" where you could set it up on an 8 base wrap sunglass with an extra drop of 5mm from the OC to the seg ht. This would be done with compensated optics and prism thinning if necessary.

There is a huge need for a high tech free form dual zone lens. The new NXT polarized is only available in Semi finished blanks and any bifocal will have to be done with free form technology anyway.

I presented this over the summer and the legal patent issue dealings along with Essilor rumors have certainly slowed new projects.

I am going to follow up again today on this project.

Craig

Now we know why Essilor bought SA! They needed to stop competing technology for Definity (dual zone progressive)

[Kyle]

No personal endorsement here, but Three Rivers offers their TR-O seg - a digitally surfaced backside "blended" round segment that can go up to (if memory is right) 40mm wide with adds from .5D up to 5D.

Their website is devoid of much information but you can call them for a faxed info sheet.

I received a sample of the lens and it's pretty dang clean with minimal distortion at the blend zone. My sample was clear Poly.

Materials/options available as reported by them:
CR39: clear, Drivewear, Transitions, Polarized
Poly: clear, Transitions, Polarized
Mid index (not given): clear, Transitions, Polarized
Trivex: clear, Transitions
1.60: clear, Polarized
1.67: clear, Transitions

They say it'll take SET, GET, Carat, Carat Advantage or Teflon

I haven't a clue on turnaround times as I've not ordered any for patients, yet, and haven't any experience with this lab beyond a handshake from the rep and the sample they sent.

kk

[Myeyeonyou]

Pixel Optics with their atLast lens has has 2 different indices infused together, Trivex and 1.67.

Any one try this yet. I took the CE course and it looks pretty cool. Reminds a little bit of the smart seg but better. :D


Never mind ~ saw the post in prog. lens forum discussing this lens.