Double PAL

**omisliebling** · 05-11-2006, 09:09 AM

Electrician patient is looking for a double PAL, one down one up in same pair of glasses. Anybody out there making such a thing ? Our lab says no, but I have heard that many times before and with some research found out they were wrong. So I'm counting on all Optiboarders.

Thanks

**Happylady** · 05-11-2006, 06:38 PM

Are you talking about a progressive that also has a reading area at the top of the lens?

Varilux used to make one called the Overview many years ago. The top had a round seg bifocal at the top. They no longer make it and I know of none availible now.

**chip anderson** · 05-11-2006, 06:51 PM

I think there are a few with St at top (probably better than a progressive at this location) and I also think that there are a couple of power options at top for various working distances, so before you order find out just how far away his upper working distance needs to be.

There is never enough room in the top for a progressive to be effective anyway, not to mention the width is insufficent in a progressive for overhead painting..
If this is no longer available I know there are a few 7/28 with an upper seg available.

Chip:cheers:

**Framebender** · 05-11-2006, 09:17 PM

you can still get double D's in various power configurations and even a couple of 7X28's with an add at the top, but no progressives. I'm not even sure how a lens like that would work. If you needed an 18mm drop in both directions and say 13 mm of static distance power, you'd need a frame with a 50 B and a damn big head to wear it!

Maybe Jacqui or Awtech might know of this animal, but I couldn't find it. Good luck to you!!

**Jacqui** · 05-11-2006, 09:47 PM

I don't know of any, and like Framebender I don't think it's really possible to do.

**Dave Nelson** · 05-11-2006, 09:53 PM

You could try inverted placement of fresnel segments placed on an existing pair of progressives, with the added benefit of being able to remove them at the end of the day.

**Happylady** · 05-12-2006, 07:46 AM

Originally Posted by Jacqui

I don't know of any, and like Framebender I don't think it's really possible to do.

The Varilux Overview had a visible round bifocal at the top, not another progressive. I still have one patient that has one. He even called a number of labs to see if he could find a pair on the shelf somewhere but with no luck. He still uses the one he has.

**chip anderson** · 05-12-2006, 08:00 AM

Dave: You may be a lot better than I at this but it often takes me half an hour to get just a pair of fresnel pasters on without bubbles. They also have a nasty habit of not adhering once they get a little foriegn matter behind them. The possiblity of a non-optical person getting these to work, removing them, and re-applying them is nil. The possiblity of them surviving in a painter's work environement is less than nil.

Chip

**Ory** · 05-12-2006, 08:20 AM

Sorry to disagree Chip but I find fresnel prisms very easy to use. I routinely use them for patients with nerve palsies to prevent diplopia. As long as you cut them to the right shape and put them on under running water the bubbles should be gone just about immediately.

There are drawbacks. They have a tendancy to fall off when going from cold to warm or vice versa (like in the winter from outside to inside). They also will come off if subjected to a significant amount of water. Light rain is ok but not heavy rain. I also lost a pair that I was trying out in my scuba mask because I forgot they were there and I rinsed it out.:hammer:

For the few dollars it would cost, why not try getting the pre-cut D-segs from 3M and see if your electrician will be able to put them on himself.

**chip anderson** · 05-12-2006, 08:29 AM

Sure would like to know your secret, especially if the patient has a steep posterior curve You do put them on the posterior surface, I presume.

**Dave Nelson** · 05-12-2006, 10:59 AM

I was actually referring to the pre-cut d segs. Yes they usually go on wet without bubbles, and they may not be the ideal answer.(if there is one) Other options would be cementing segments on, or simply a clip-on flip-up reader, which I sometimes use for fly fishermen who want to see to put the fly on the line.

**Chris Ryser** · 05-12-2006, 11:05 AM

Originally Posted by omisliebling

Electrician patient is looking for a double PAL, one down one up in same pair of glasses.
Thanks

The poor guy will fall off his ladder full dizziness................with a lens 3/4 full of distortion if you could ever find one to sell to the guy.

Do like they did years ago and sell him a vocational ST and you wont have to worry about a lawsuit for selling him a distorted vision for a high price.. :hammer:

**HarryChiling** · 05-12-2006, 12:41 PM

Originally Posted by Dave Nelson

I was actually referring to the pre-cut d segs. Yes they usually go on wet without bubbles, and they may not be the ideal answer.(if there is one) Other options would be cementing segments on, or simply a clip-on flip-up reader, which I sometimes use for fly fishermen who want to see to put the fly on the line.

This would actually present a solution. Use a clip on frame to edge a pair of progressives into upside down. Make the distant plano in the clip on progressives. I would recommend not using prism thinning in the clip to avoid any wierd image jump. I know this would be an awfull solution, but it acomplishes what you asked for.

**Ory** · 05-12-2006, 05:09 PM

If we're going for awful solutions......

Could you not make a Franklin bifocal out of 2 progressives with the division near centre? Ewwwww......
And Chip, back to the fresnel prisms, I do put them on the back surface. I've found as long as you have enough water trapped under the lens it will work well. You may have to leave it to dry for a while. I just saw a patient that I put a full lens prism on his specs 2 months ago and it is still on there. Sorry, I don't know the posterior curve off the top of my head.

**Dave Nelson** · 05-12-2006, 05:31 PM

Awful solutions is right. Seriously though, the d segs are (or were) available as fresnels, but since the thickness is negligible, they are also made in "full form." they do tend to cling well, and are often used on the inside of sunglasses, so the presbyope can read, but the tint hides the tell-tale seg line. At the end of the day, I tend to agree with Chris R. Just get him the double d vocationals, and live with it.

**Ory** · 05-12-2006, 05:57 PM

Dave: They are still available. I get them from White Ophthalmic. Basically the D-seg ones are just a +2.00 or whatever in a full sized fresnel that is perforated into 2 segs.

Actually an advantage to just getting a full fresnel lens is you could put power anywhere in the lens (top, sides, in a ring around the whole lens). However, I will agree that the double D-segs is the best choice.

**Jacqui** · 05-12-2006, 07:54 PM

Originally Posted by Ory

If we're going for awful solutions......

Could you not make a Franklin bifocal out of 2 progressives with the division near centre? Ewwwww......
And Chip, back to the fresnel prisms, I do put them on the back surface. I've found as long as you have enough water trapped under the lens it will work well. You may have to leave it to dry for a while. I just saw a patient that I put a full lens prism on his specs 2 months ago and it is still on there. Sorry, I don't know the posterior curve off the top of my head.

You could use a Franklin, BUT, you would still have the height problem.

**Clive Noble** · 05-14-2006, 10:47 PM

1) You could get one of the specialist labs to make a wafer lens of the power needed, (say +1.75) and have them cement it at the required position at the top of the progressive lens

2) I have actually made a Franklin bifocal at the top of a PAL for an electrician, not the best looking piece of work, but it did work for him.

3) And just by chance, I saw a Pt in the street still wearing a Fresnel Prism of 5^ out which we 'temporarily' gave him a couple of years ago.... he is unbelievably happy with it even though it has yellowed so badly.....
It looks horrendous.....
I did ask him not to mention to his friends where he had his glasses made!