New glasses - acceptable workmanship?

[Kiwi79]

Got a new pair of glasses recently. Went for slightly thinner lenses and I've noticed that the optician (well their lab) seem to have ground the back of the lense to make it sit flush with the plastic frame when viewed from the side. The downside of this is that when viewed from the front you get a visible white mark area where the lense which has been ground at the back shows through.

Is this standard practice on a clear lense into plastic frame? (FYI prescription is -4, lenses 1.6, frames plastic) - just seems weird.

[cringle]

Yes that’s normal. You’d need a thicker frame to hide it. Just double checked with OH who is an optometrist

[Kiwi79]

Thanks for checking Cringle, I was just curious as on previous glasses I have the lenses just overhang the back of the frame a bit (not a problem IMO) but you don't get this odd look from the front from the grinding on the back. Maybe it's all edged automatically by machine nowadays and there's no control over that depth aspect.

[HelenT]

I'm an optometrist but we do our own glazing, generally we don't polish the edges unless requested as many people find it causes annoying reflections. The contrast between the edge and the rest of the lens is probably more noticable with modern coated lenses which appear so clear.

[Kiwi79]

HelenT said:

I'm an optometrist but we do our own glazing, generally we don't polish the edges unless requested as many people find it causes annoying reflections. The contrast between the edge and the rest of the lens is probably more noticable with modern coated lenses which appear so clear.

Interesting wasn’t aware of that. Would it be fair to say there are several options for edge finish:

-Polished
- Unpolished
On the actual edge

And then whether the lense it left to reach its natural curvature (e.g has a sharper feeling/right angle to the edge and side on Would potentially stick out beyond the frame depending upon frame/index/prescription) or is ground flat to frame?

If you go for unpolished as these appear to be do you normally then grind the back of the edge flush to the back of the frame so from side on they don’t protrude from the frame?

[HelenT]

Kiwi79 said:

Interesting wasn’t aware of that. Would it be fair to say there are several options for edge finish:

-Polished
- Unpolished
On the actual edge

And then whether the lense it left to reach its natural curvature (e.g has a sharper feeling/right angle to the edge and side on Would potentially stick out beyond the frame depending upon frame/index/prescription) or is ground flat to frame?

If you go for unpolished as these appear to be do you normally then grind the back of the edge flush to the back of the frame so from side on they don’t protrude from the frame?

Frame shape and size is a big factor, fashion is going bigger frame wise which gives more edge thichness on a myopic lens, lens design is also a balance between cosmetic appearance and optical performance, so thinner flatter lenses tend to have more peripheral distortion.Depends on whether your Optician has in house glazing or not but you could ask them to polish the lens edges.