Progressives

**opticianbart** · 10-28-2009, 02:52 PM

I know everyone has a different opinion concerning progressives. For that matter different progressives are better for different things. Our shop uses a Zeiss lab, and almost all the progressives we do are the Zeiss ones. I've been told that they don't have hardly any soft focus in the distance peripheral area. I've also been told that they are the only ones in which this is true. However, I've also learned to take what the Reps say with a grain of salt... (or two) So I'm wondering what ya'll's thoughts on progressives are. Are the Zeiss ones the only ones where you'll not end up with peripheral distortion in the distance area? Do the Zeiss progressives even do that?

thoughts? comments? unrelated ramblings?

**braheem24** · 10-28-2009, 03:00 PM

There are a lot of progressives with no distortion above the 180 line, most of them also happen to be the cheapest, oldest designs.

2 popular ones are image and concord.

**Happylady** · 10-28-2009, 04:36 PM

When they compare different progressives they usually compare them with a plano distance and a +2.00 add. In reality, when you add a distance correction it completely changes how the lenses look when they are plotted.

And often lenses that have a really good distance have a smaller reading area and are harder in design. Harder design lenses can be swimmier and less comfortable to wear.

**TLG** · 10-28-2009, 07:05 PM

I have personally worn over a dozen PAL designs, including freeform. They ALL had peripheral distortion, some more or less than others of course. I don't think it's realistic to believe that peripheral clarity will be equal to straight ahead in any lens. If anyone disagrees, I would love to try your suggestion (I'm monovision-amblyopic-so would love to find a great solution).
The best I've tried as far as peripheral clarity happens to be the Image as noted above. I have them in polarized only and although the reading area is dinky, the clarity across the periphery is impressive (I believe that dark lenses help to mask problems in PALs so that may be a part of it).

**FVCCHRIS** · 10-28-2009, 07:33 PM

Originally Posted by TLG

I have personally worn over a dozen PAL designs, including freeform. They ALL had peripheral distortion, some more or less than others of course. I don't think it's realistic to believe that peripheral clarity will be equal to straight ahead in any lens. If anyone disagrees, I would love to try your suggestion (I'm monovision-amblyopic-so would love to find a great solution).
The best I've tried as far as peripheral clarity happens to be the Image as noted above. I have them in polarized only and although the reading area is dinky, the clarity across the periphery is impressive (I believe that dark lenses help to mask problems in PALs so that may be a part of it).

Your comment about the tint intrigues me and makes sense. Any increase in the amount of light reaching the eye would make seeing anything better- including BAD things. I think I'll figure out a way to tint only the peripheral areas of progressives so they are less annoying to patients. Or how about a drill mount frame where we just wack those areas off with a jigsaw?? That would make for some interesting lens shapes and make patients use only the "sweet" parts of their lens. I think it would look really high-tech also. What should we call it Tony??? :shiner: Very-Lucks?

**braheem24** · 10-28-2009, 09:18 PM

Originally Posted by TLG

I have personally worn over a dozen PAL designs, including freeform. They ALL had peripheral distortion, some more or less than others of course. I don't think it's realistic to believe that peripheral clarity will be equal to straight ahead in any lens. If anyone disagrees, I would love to try your suggestion (I'm monovision-amblyopic-so would love to find a great solution).
The best I've tried as far as peripheral clarity happens to be the Image as noted above. I have them in polarized only and although the reading area is dinky, the clarity across the periphery is impressive (I believe that dark lenses help to mask problems in PALs so that may be a part of it).

pm me your rx and address.

**Yeap** · 10-28-2009, 09:31 PM

As i have told by the Zeiss rep, that is something called optimize design which means no matter what Rx you have change the vision for far, inter and near also peripheral distortion will be about the same. also we have some wearer that play golf very frequent said that it is very good for far vision. but sad thing for frequent reader they still prefer the Sola One design..

**Chris Ryser** · 10-29-2009, 02:57 AM

Originally Posted by opticianbart

Are the Zeiss ones the only ones where you'll not end up with peripheral distortion in the distance area? Do the Zeiss progressives even do that?

thoughts? comments? unrelated ramblings?

No, the Zeiss are not the only ones with distortion...............ALL of them have it. The only difference is, that they have found a new term for the word distortion and call it now lateral astigmatism.

Ug......Ug eat bug......Ug eat slug......Ug choke on slug..........Ug. Ug. Ug.

Freeform or not, they still all of them have it. Distortion or lateral astigmatism whatever you want to call it.

They were originally made as an invisible bifocal with a progressively increasing power (which is the origin of the distortion) to replace trifocals, but the main reason for wide acceptance specially by women was the hiding of their age being over 40, given away by wearing conventional bifocals.

The higher the reading add gets, and it will, due to advancing age, the distortion gets more visible and disturbing and the reading area gets drastically smaller.
With a reading additions over + 2.25, progressive lens users can not even get a wider reading area than 1 column in a newspapers classified ads.

Due to the late fashion of very small frames over the last few years, progressive lenses have been prostituted by manufacturers as well as retailers by supplying short channel lenses that leave the wearer of glasses with minimal areas of clear vision. There must be millions of people in North America alone that are wearing progressive lenses in tiny frames that barely have a few millimeters of reading area left.

When todays Essilor came out with the first Varilux they gave courses for opticians in every area in Europe. They taught the professionals how to fit those lenses. They recommended to sell them to first users when there was a small reading addition involved so they would have the widest areas with the smallest distorted areas and the progressively get to higher add as customers got older and were used to them.
They also warned opticians not to convert older people from bifocals to progressives as they would not adapt to them and the lenses were a loss by then. There was no warranty for non adapt.

In 1963 they made advances to introduce them in Canada first. There was a lot of feelings against these lenses among professionals at the time. I know because I did the feasibility study for them. It took a long time to get them going and only after introducing the non adapt warranty, which got optical retailers off the hook financially, progressives finally took off.

Many more have been introduced over the years by just about very lens manufacturer, new names, new features, new materials old ones repacked as new ones. Sold at lower prices to chains under other names. Everyone claim to be better than the other........................but they are still the old hat, with plenty of distortion, whatever name you want to call it, and superbly small reading areas when you get into higher additions.

However due the brainwash advertising by the large manufacturers to wards the unknowing public and being a very profitable item for everybody, these optically impure lenses will continue to glow as the ultimate solution for good and perfect vision.

Ug......Ug eat bug......Ug eat slug......Ug choke on slug..........Ug. Ug. Ug.

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**thep** · 10-29-2009, 09:28 AM

However, I've also learned to take what the Reps say with a grain of salt... (or two)

you may want to add some kool-aid to that..I'm just say'n

**DragonLensmanWV** · 10-29-2009, 10:15 AM

Originally Posted by FVCCHRIS

Your comment about the tint intrigues me and makes sense. Any increase in the amount of light reaching the eye would make seeing anything better- including BAD things. I think I'll figure out a way to tint only the peripheral areas of progressives so they are less annoying to patients. Or how about a drill mount frame where we just wack those areas off with a jigsaw?? That would make for some interesting lens shapes and make patients use only the "sweet" parts of their lens. I think it would look really high-tech also. What should we call it Tony??? :shiner: Very-Lucks?

How about this? I call it the Sweet Spot shape.

**FVCCHRIS** · 10-30-2009, 05:06 PM

Now that's what I'm talkin' about!:shiner:

**sandeepgoodbole** · 10-31-2009, 07:39 AM

Oh ! Steve, Seeds above may germinate in to 'Anti Progressive' Forum ?!The fact that they cannt fool billions the contemporary time, suggests that the tolarance of all the peripheral, corridorial and the bottom most distortion is within acceptable levels of the majority as compaired to what they face if not using any aid at all, or using any thing like multiple svs, bifocals trifocals. Better not to over look the Filled portion of the Glasses and the Rxs.!!!

**ilanh** · 10-31-2009, 12:06 PM

Originally Posted by TLG

I have personally worn over a dozen PAL designs, including freeform. They ALL had peripheral distortion, some more or less than others of course. I don't think it's realistic to believe that peripheral clarity will be equal to straight ahead in any lens. If anyone disagrees, I would love to try your suggestion (I'm monovision-amblyopic-so would love to find a great solution).
The best I've tried as far as peripheral clarity happens to be the Image as noted above. I have them in polarized only and although the reading area is dinky, the clarity across the periphery is impressive (I believe that dark lenses help to mask problems in PALs so that may be a part of it).

What Braheem told you is true. Image, Concord (and others) will give you absolute undistorted vision above the 180 line. The problem lies with their interm and near.

**Barry Santini** · 10-31-2009, 12:37 PM

I think a partial answer to the observation we've all encountered where clients will comment that the tinted or sun tinted glasses they're just getting "look better" or less distorted is that the tint lowers the contrast gradient.

This makes the reduced clarity (contrast) of the periphery less noticeable compared with the higher contrast of central vision in progressive (and other) lenses.

My take, FWIW

Barry

**opticianbart** · 11-03-2009, 03:53 PM

thanks everybody!
:)
I love being able to pick brains on here.

**Darryl Meister** · 11-04-2009, 12:05 AM

No, the Zeiss are not the only ones with distortion...............ALL of them have it.

Keep in mind that, while all progressive lenses have unwanted astigmatism and distortion in the peripheral regions of the lens as you suggest, not necessarily all progressive lenses have these aberrations in the distance periphery, which was the original question.

ZEISS progressive lenses do indeed maintain extremly low levels of unwanted astigmatism and distortion above the "180" line of the lens. This is not to say, however, that ZEISS lenses are the only progressive lenses with this feature.

The only difference is, that they have found a new term for the word distortion and call it now lateral astigmatism

In optics, "distortion" refers to a specific type of magnification effect. "Astigmatism," on the other hand, refers to a power effect, which in progressive lenses is produced by differences in curvature in the periphery of the lens.

Although these terms may be used interchangeably or even misused in some cases, neither term is new. When describing the optics of a progressive lens though, it helps to distinguish between the two effects.