yellow fringes

[dmitrijsg123]

Px seeing yellow fringes just below the upper rim (along it) when looking at bright source of light. + 2.50 or so Rx. Anti-glare coating. the lenses have polished edges. I "unpolished" the edges, it made it better but still Px complaining that some of it can be seen, even though not as much. Is it TCA? Will removal of the MAR help it or make the aberrations even worse?

[uncut]

What is the index of refraction/material used for the lens, dmitrijsg123?

[Judy Canty]

What color is the frame?

[obiwan]

It's chromatic aberration. Polycarb lenses?

[dmitrijsg123]

it is Pentax Thin and Light 1.6 plastic.

[dmitrijsg123]

It is metal double-rimmed purple frame.

[uncut]

it is Pentax Thin and Light 1.6 plastic.

I think obiwan is correct, the cause is likely the chromatic abberation of the 1.6 material. Find out the abbe value from the manufacturer, and compare it to other "brands" to help in the future. Unpolishing the edges helped, as you state. Removal of the anti-reflection coating would only exacerbate the color fringe issue. A change to a different index, or brand, that has a better Abbe value would remove this phenomena.

[MakeOptics]

As a last resort you may consider checking the curves and powers against a chart for ghost images. On rare occasion a faint double image can be seen if the clients focal power and the reflected secondary image are focused just right. If the problem is due to the edge of the lens you may even consider a edge coat to darken the edges or a quick dip in the tint tank.

[dmitrijsg123]

Thanks very much!!

[Robert Martellaro]

Px seeing yellow fringes just below the upper rim (along it) when looking at bright source of light.

Don't look up at a bright light source when looking through the superior bevel of the lens!

+ 2.50 or so Rx.

CA is unlikely at this power, even if the material is very dispersive, poly, for instance.

Anti-glare coating. the lenses have polished edges. I "unpolished" the edges, it made it better but still Px complaining that some of it can be seen, even though not as much.

There's your answer. Keep working the edge, maybe introduce some color by dye, or one of those edge tinting pens. Reduce the vertex distance and/or panto tilt.