Foggy eyeglass lenses have always been annoying, but since most of us have been wearing masks to protect ourselves and others from COVID-19, the problem has become widespread.

A growing number of suppliers are now producing special lenses and coatings that fight fog, as VMAIL has previously reported. And some VMail readers have made suggestions for how to minimize the moisture that collects on our lenses when we breathe.

We’ve asked dispensing expert and 20/20 Magazine contributing editor Palmer R. Cook to weigh in on the discussion. Here’s his take on the topic.

X-Soap for De-Fogging Lenses
Prior to the advent of standard plastic, the most common ophthalmic lens material was glass, as I am sure most VMAIL readers know. In the 1960s there was quite a marketing battle between the glass ophthalmic lens manufacturers and those that wanted to promote plastic lenses. For a short period, the plastic lens promoters recommended telling patients that plastic lenses would not fog up as readily as glass lenses. This is a true statement however it does not pass the test of being a “patient perceptible” difference. Patients who made the lighter weight choice of plastic with its greater “scratch-ability” and a lower Abbe value returned with complaints including, “They still fog up and they are not as clear.” The not-as-clear part was primarily due to chromatic aberration. The blowback from dispensers to the manufacturers led to an abrupt withdrawal of the less fogging claim.

A fair home test for any reduction in fogging due to some treatment would be to treat one lens and not the other, and then chill the lenses in the freezer. After a thorough chilling, the lenses can be removed to a warm, moist environment and a comparison can be made. If you are an ECP, you can use samples of fog-resistant products to test their efficacy in your home or office.

Many men are aware that if they want to use the mirror when shaving in a warm and steamy bathroom they can dab some shaving cream on the mirror and gently clean the foam away, leaving a thin film of soap on the mirror. This causes the mirror to become temporarily more hydrophobic and the cleaned area will not fog up. Shaving cream is not practical for spectacle lenses because the shaving cream gets into the eyewire groove and other parts of the eyewear and must be rinsed away generally cause a loss of the needed soap film on the lenses.

The face masks with built-in relief valves might reduce fogging somewhat if the upper seal of the mask is tight, however these masks expose others to the virus if the wearer is infected, an issue the CDC recently addressed.

It might surprise you to know that patients in colder climates are sometimes critical of the fact that their new spectacle lenses fog more than their old lenses. Because I was teaching, I did 10-day follow-ups on spectacle lens patients for many years and I repeatedly heard this comment. In fact, those patients’ reports were quite accurate. Older lenses tend to have a thin film of oils that inhibit fogging to some extent, while pristine, new lens surfaces do not have the same resistance to fogging. While some anti-reflective products have an oleophobic coating to make the smudge resistant, they seem to be not very efficient in reducing lens fogging while wearing a mask.

Here’s What Works

A good seal at the top of the mask that compels the moist exhaled breath to escape through the filtering mask or from the bottom of sides of the masks might work, but there could be a risk of inhaling unfiltered air through those portals.

A more practical solution is to clean the lenses thoroughly with a recommended lens cleaning product. Then use the corner of a bar of hand soap to draw a large X on all four lens surfaces. Next use a clean tissue to gently clean the soap while leaving a thin soap deposit over each surface. This can be used for face masks, and for people whose work takes them in-and-out of large freezers or cold environments of any kind to warm moist areas.

Unfortunately, this does not work well on a AR lens surfaces because the soap film smears, and if the film is completely removed the anti-fogging effect is likewise removed. An alternative is to use the X-Soap method on sunglasses, which rarely have AR lenses, and wear them while you are shopping or in other risky environments. X-Soap could be any common hand soap that does not contain abrasives (e.g. Lava) or soaps containing hand creams.

Because the eyes can be portal of entry for infections, reminding people to wear some kind of eye covering when exposure to the virus is possible and to keep their hands away from their eyes is a responsibility that all ECPs should shoulder.

As an aside, I sometimes open my front door so my two indoor cats can watch the birds and squirrels in the yard. In cold weather the storm door’s lower panel totally fogs up. I use a dab of shaving cream to clear the window and treat the all-too-spoiled felines.