Glasses acquire tinge

**Pato** · 12-10-2018, 01:41 PM

I have just had my prescription glasses changed, and over the last week they appear to have obtained a yellow tinge.

This is something new to me and am wondering if anyone else has experienced this.?

**wainuitech** · 12-10-2018, 02:28 PM

Could be several reasons, never had the problem myself, but doing a google search found some causes: https://www.quora.com/Why-do-eyeglas...es-turn-yellow

Mighty be an idea to contact the place you got them from and ask them, in case there is some sort of problem. Better to get it sorted sooner than later.

**Pato** · 12-10-2018, 03:18 PM

I intend seeing the optician but just thought I would ask on here in case someone else had seen this problem. I have had many changes of lens over the years and I haven't seen this before either.

They cost an arm and a leg so I will certainly get it sorted.

**1101** · 12-10-2018, 04:22 PM

Slightly offtopic (sorry) ,but whats good to clean reading glasses ?

**Lurking** · 12-10-2018, 04:36 PM

Specsavers Lens Bright is good.

**wainuitech** · 12-10-2018, 08:15 PM

Originally Posted by Lurking

Specsavers Lens Bright is good.

Also good for cleaning Computer screens

**Bryan** · 12-10-2018, 08:17 PM

Wash them and dry with toilet paper

**dugimodo** · 12-10-2018, 09:01 PM

I use specsavers for my prescription and 1 pair of glasses, I buy a second pair and some precscription sunglasses at Zenni online for a fraction of the cost.

Never seen any lenses turn yellow though.

**Kame** · 13-10-2018, 12:22 AM

A lot of lenses nowadays are made out of CR39, a plastic polymer, rather than glass because its cheaper, lighter and more impact resistant. However, it has a shorter life when exposed to sunlight a lot which causes it to turn yellow. Chemical reaction or oxidisation, like car headlights. It's life expectancy is around 2 years if you're lucky. The only way I know how to increase it's life is to clear coat (transparent paint) your lenses but it affects the visual clarity and is only worth it if you continue to buy them here and don't want to replace them as often.

The cost is not cheap in NZ, which is why I use my eye report to purchase my glasses overseas. Glass is better at an optical scale but it's heavier, can shatter easier and as a result, cause your eyes harm.

CR39 isn't bad but NZ definitely does not reflect its cheaper manufacturing cost appropriately here, they continue to ride the value of what glass would have cost. Definitely avoid their sales pitch.

If you don't mind the weight, glass is better with helping your eyes. If you use your glasses as safety too, then you may want polycarbonate lenses but I wouldnt use them as your regular glasses, as again its lower on the optical scale but has higher impact resistance.

Glass > CR39 > Polycarbonate

**Paul.Cov** · 13-10-2018, 10:06 PM

Oooh, well informed reply up there from Kame.

I'll add a couple of other possibilities... the lenses might be photochromic (aka Transitions or 'ChangeLight'). These commonly have a slight residual tint. The older generation of the tech in particular has this mild yellowing.

Or, there might have been a UV block added to the lenses, which also tends to add a low degree of yellowing.