This is not a Halloween post, it is about an issue that can happen any time of year – I had been wearing my favorite progressive sunglasses for over a year, the frame is named after me: “Shirley” by frieze frames, just kidding not really named after me, pure coincidence! I had a beautiful silver flash mirror coat applied. A couple of months ago I thought I had scratched the lenses but over the next couple of weeks I realized they were not scratched but I could see the progressive ink markings coming through. Two weeks later the markings were even more visible. Yikes, I was the victim of “ghosting”, very Halloween like but I was not amused and just a bit irritated as I could no longer wear my favorite prescription sunglasses.
But being in the optical industry I do have back up so not so bad for me. However, I thought this would not be a good experience for a regular eyewear consumer so I researched the topic for more information.
Michael Bellomo of Opticote informed me that this issue is known as “ghosting” and not an uncommon problem. I checked in with a couple of our lens sponsors and searched for it on Optiboard and found a 9 year old running thread on the subject! Bottom line it seems that not cleaning the progressive lens markings off completely is the most common cause of “ghosting”! Ways to avoid it…..
Sue Klein from the tech department at Vision-Ease Lens was very helpful and explained that this ghostly and costly lens issue can be caused by the lens manufacturer or the lab. If the lens manufacturer does not cure the coating completely before the progressive ink markings are applied it can cause a ghosting issue later. But the most common reason is not removing the markings completely after the lens has been surfaced. Vision-Ease recommends using isopropyl alcohol, not acetone, especially for polycarbonate.
Opti-Board Thread Comments: (Special thanks to Chris Ryser who responded to my question this week!)
- Aberdeen Angus: “Hilco do products called “solves it” and “solves it for poly” as you would expect the second is safe for polycarbonate. It’s what we use and it takes the marking of all of the brands we sell. Essilor marking take a bit longer though, so if its not polycarb I use acetone. It’s very handy because it comes in a pen applicator, so no need to worry about spillage.”
- VSTAR: “I have been using for 20 years a product that is non-acetone and works great. In fact there are now 2 products available in the Toronto area. I found the problem with Acetone to be not on the lenses but on the frame. Some plastic frames and some of the finishes on metal frames (and not always the cheap ones) would react to the acetone and the finish was ruined. Strong rubbing alcohol would work – with a lot of effort. But the specific products made for the optical industry with no acetone work fantastic. If you need the contact in Ontario Canada send me a reply and I will look it up at the office.”
- Chris Ryser: Use a proper ink remover made for that purpose that does not harm lens material nor coatings. There are several different ones available on the market. They will properly dissolve the markings and you can wash off the residues so that you will not start to see them again because they were not properly rubbed off.