Lens Thinning methods

[sportywei]

In Singapore, cosmetic appearance of one's eyeglasses is far more important than the features which the lenses provide.

People would complain about the yellowish tint that makes up the bulk of the ultra-violet protection you would get from the ophthalmic lenses. FACT of life; FIRST impression does really counts.....

Main question, For Minus lenses, we could adjust its overall thickness from a specific material by altering the center thickness of the lens. For plus powers, we could alter by reducing the lens diameter or by applying a edge surfacing technique called: "Knife Edge" and " Ellipse Knife Edge"....

Are there any other more techniques to reduce overall thickness of the lens by such methods?

[Rich R]

On high power lenses where the optical center sits vertically makes an impact on cosmetics and lens overall thickness, picking a frame that sits as close as possible with pupils centered vertically and requesting o.c. heights closer to center will reduce thickness and improve cosmetics considerably.
Rich R

[chip anderson]

I assume you people know about lenticulation, asphericity, tapering and rolling non visual areas.
We can't use knife-edge in the US, not on spectacles anyway. Our government "protects" us from such things.

Chip

[mike.elmes]

In Singapore, cosmetic appearance of one's eyeglasses is far more important than the features which the lenses provide.

People would complain about the yellowish tint that makes up the bulk of the ultra-violet protection you would get from the ophthalmic lenses. FACT of life; FIRST impression does really counts.....

Main question, For Minus lenses, we could adjust its overall thickness from a specific material by altering the center thickness of the lens. For plus powers, we could alter by reducing the lens diameter or by applying a edge surfacing technique called: "Knife Edge" and " Ellipse Knife Edge"....

Are there any other more techniques to reduce overall thickness of the lens by such methods?

We sell a water white lens with 100% UV protection....mainly because most customers DO NOT want a yellow tint!

[cocoisland58]

I've asked for knife edge and if the blanks I recieved weren't they were pretty darn close.

[MarcE]

I've asked for knife edge and if the blanks I recieved weren't they were pretty darn close.

I too get pretty good knife edges. Is my lab not protecting me?

[RT]

The only reference to edge thickness in ANSI Z80.1-2005 is in Annex A, where it states that air tempered glass lenses have an edge thickness of at least 1.0 mm.

[Chris Ryser]

We sell a water white lens with 100% UV protection....mainly because most customers DO NOT want a yellow tint!

I love this one..........................................

To all of you guy's and girls in the optical retail that are doing that...............are cheating the customer and themselves.

Water clear UV treated lenses do not absorb UV to 400nm.

Clear UV stops absorbing UV A at 382 nm and does not even go to 400nm

Every lens made these days absorbs all UV B up to 360 nm. Every lens manufacturer ads this UV absorber so lenses will not yellow by exposing them to daylight.

By treating the lenses with a clear UV solution you will protect the customer only half way to the full 400nm protection the customer expects. So there is nothing to be proud of.

There is only one nearly clear UV Solution on the market that does make it to 397nm that I know of.



check at: http://optochemicals.com/main-english.htm

or at: http://optochemicals.com/prism_article.htm

[sportywei]

xx

[gemstone]

I love this one..........................................

To all of you guy's and girls in the optical retail that are doing that...............are cheating the customer and themselves.

Water clear UV treated lenses do not absorb UV to 400nm.

Clear UV stops absorbing UV A at 382 nm and does not even go to 400nm

Every lens made these days absorbs all UV B up to 360 nm. Every lens manufacturer ads this UV absorber so lenses will not yellow by exposing them to daylight.

By treating the lenses with a clear UV solution you will protect the customer only half way to the full 400nm protection the customer expects. So there is nothing to be proud of.

There is only one nearly clear UV Solution on the market that does make it to 397nm that I know of.



check at: http://optochemicals.com/main-english.htm

or at: http://optochemicals.com/prism_article.htm

The above statement does not jibe with this. http://www.opticampus.com/tools/materials.php

[mike.elmes]

Ahh Chris, always trying to sell your UV chemicals:D....In this day and age, I am moving away from CR39 to better lens materials which have inherently better UV inhibiting properties. No glasses should have to be yellow to inhibit UV, they should be poly, Trivex, TL16 or 167 and then lens is water white & clear as a bell.
Also, we sell more polarized lenses(for sunwear) now than ever. Clips, have also gained in popularity.... so the UV treatment is not a requirement, at least in the everyday glasses if the right lens material is chosen.

[Win C]

Are there any other more techniques to reduce overall thickness of the lens by such methods?

I had a px with a RX of +9.00 DS. He chose a frame with an eye size of 53. I gave him a Hoya 1.7 single vision with METS calculation for min thinkness. It was amazingly thin....shaved off about 3mm of centre thickness from his old lens.

[gemstone]

I had a px with a RX of +9.00 DS. He chose a frame with an eye size of 53. I gave him a Hoya 1.7 single vision with METS calculation for min thinkness. It was amazingly thin....shaved off about 3mm of centre thickness from his old lens.

He was probable fine with the slight yellowis color you get with those Hoya products.