Aspheric polycarbonate vs hi index lenses

**monicafaye** · 09-09-2006, 08:56 AM

Are aspheric polycarbonate as thin as high index lens for high power rx? Which has less visual distortion but also good cosmetic appearance? Thanks

**chip anderson** · 09-09-2006, 09:22 AM

High index has less visual distortion, probably better cosmetic appearance. As to thickness it would depend on individual application and design of asphericity.

**HarryChiling** · 09-09-2006, 10:14 AM

You wil also find that most high index lenses will be aspheric, my personal preference is for high index. As Chip mentioned poly has a high amount of chormatic abberation. Most people will never even notice the difference, but there is the small percentage of people who notice. Also high index is a little less prone to scratches and their are even tricks to removing small scratches from high index.

**Happylady** · 09-09-2006, 12:03 PM

Originally Posted by HarryChiling

You wil also find that most high index lenses will be aspheric, my personal preference is for high index. As Chip mentioned poly has a high amount of chormatic abberation. Most people will never even notice the difference, but there is the small percentage of people who notice. Also high index is a little less prone to scratches and their are even tricks to removing small scratches from high index.

What tricks are there to removing scratches from high index?

**chip anderson** · 09-09-2006, 12:29 PM

Under present Govermental guidelines, the only method of removing scractches permitted seems to be new lenses on any material.

**HarryChiling** · 09-09-2006, 01:50 PM

What tricks are there to removing scratches from high index?

Check this link out:

http://www.laramyk.com/learn/tip_remove_scratches.html

**chip anderson** · 09-09-2006, 02:11 PM

I stands corrected. Now what effect will the hot water and microwaves have on the various coatings on the lenses?

Thanks Harry,

**HarryChiling** · 09-09-2006, 02:23 PM

Originally Posted by chip anderson

Now what effect will the hot water and microwaves have on the various coatings on the lenses?

That is a good question, I don't know how the coating would be affected, but I would venture to say that it wouldn't be too different than tinting a high index lens. This of course is only a hypothesis.

**Happylady** · 09-09-2006, 02:55 PM

Originally Posted by chip anderson

I stands corrected. Now what effect will the hot water and microwaves have on the various coatings on the lenses?

Thanks Harry,

Do this work if the lenses have an AR Coat?

**thep** · 09-09-2006, 03:33 PM

No, you don't want to subject ANY A.R. coated lens to ANY type of heat process. It works miracles on 1.6 and on 1.66 without harming the scratch coating though!!