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Helping Treat Migraines, Blepharospasm, and Other Light-Sensitive Conditions

The FL-41 filter is a "boysenberry-ish" colored tint that can help ease:

  • migraine headaches,
  • blepharospasm,
  • light-triggered seizures,
  • CVS (Computer Vision Syndrome), and
  • other light-sensitive/triggered conditions.

FL-41 was first described in a research project that took place in Birmingham, England in the early 90s. In this study, children with migraine headaches wore FL-41 filtered spectacles.

The researchers found that wearing the FL-41 filter improved the light sensitivity in these children, as well as lessened the frequency and severity of their migraine headaches. Since that time, FL-41 filtered lenses have been used to treat these and other conditions.

Aided by funding from the Benign Essential Blepharospasm Research Foundation, we have found that blepharospasm and migraine patients suffer more from light sensitivity, vs. people who do not struggle with these conditions. We have also found that when these patients have had their light sensitivity treated, their blepharospasm and migraine symptoms have improved.

Recently, we have tested FL-41 filtered lenses, head-to-head, against conventional gray sunglasses and standard rose tinted spectacles. We have found that the majority of patients prefer wearing FL-41 filtered spectacles.

Tray of FL-41 eyeglasses.
FL-41 Lens Samples
A sample of FL-41 lens colors.

How to Order FL-41 Lenses

To order FL-41, please download our order form and patient release form.

For more information, contact:
Mr. Patrick Shaw
Phone: 801-581-2352, Option 5

Toll Free: 877-248-6374
Fax: 801-587-3764

Frequently Asked Questions


How does the FL-41 filter work? 

Although we are not completely sure why FL-41 improves light sensitivity, it seems to have something to do with the wavelengths/spectrums of light that are filtered out.  FL-41 filters out certain wavelengths of blue and green. These colors are thought to be particularly bothersome to patients with light sensitivity. By blocking these wavelengths of light, this filter also improves contrast and sharpness which increases visual acuity.

Can the FL-41 filter be added to any lenses? 

The FL-41 filter can be applied to most any lens material – providing it DOES NOT have any coatings applied to it beforehand – i.e. – no hard coats, scratch coats, UVA/UVB filters, anti- reflective (AR) treatments, or other tints/filters, etc. These coatings, if wanted, can be done after the FL-41 filter has been applied to the lenses. If you’re wanting a dark FL-41 filter, CR-39 plastic would be the best lens material, as it is a more porous material and can absorb the filter more deeply. Light to medium FL-41 filter can be done on pretty much any lens material.

Does insurance cover the cost of FL-41 filter? 

Most insurance plans, including Medicare and Medicaid, do not cover the cost of adding filters to lenses. However, there may be exceptions, so contact your individual insurance provider.

Are there any side effects from wearing FL-41 filter?  There are no known side effects from wearing the filter.

Can the FL-41 filter be worn indoors and outdoors? 

The FL-41 filter can be worn indoors and/or outdoors. However, that having been said, the FL-41 filter is typically used and seems to be more beneficial in an indoor arena and setting. The "FL" in FL-41 stands for "fluorescent." We’ve found that most patients prefer some type of polarized lens out of doors. There are a few, though, who do prefer the FL-41 filter outdoors, as well as indoors. Some will get one pair (lighter) for indoors and one pair (darker) for outdoors. If you’re wanting them for multiple settings/environments, more than one pair will typically be needed.

How much does the FL-41 filter cost? 

The FL-41 filter, alone, is $35, plus tax. From there, it just depends on your prescription and what "add-ons" you’re needing/wanting.

Can I still get the FL-41 filter if I live out of state/country?  Yes. In this case, we send you an FL-41 filter order form – which we will need you to fill out completely. You would then mail that order form, along with your own frame(s) – (we ask that you provide your own frame(s) to ensure style, fit, comfort, etc.) - and we will build the lenses from there. We do not accept lenses from other facilities/opticals. Should you be needing Rx lenses – and not just the filter – we will need a current, dated and signed spectacle prescription, as well as Rx/lens measurements – i.e. – PD (pupillary distance) and/or a seg. ht. – for any type of multi-focal.

Shipping costs, for in and out of state orders, are a flat $10 – in addition to your order total. Out of country shipping costs will vary. We do charge sales tax on orders – even if your state or country does not charge sales tax. The current Utah sales tax rate is 6.85% on the dollar.

Where can I get the FL-41 filter?

  • Any Moran Eye Center location with an optical shop, throughout Utah, 801-587-3765 
  • Frameworks Eyewear in Sandy, Utah, 801-576-6433
  • Eyeworks Optical in Ogden, Utah, 801-479-1100
  • Mr. Peabody’s Optical Shop in Boise, Idaho, 208-344-1390
  • Tanner Clinic in Layton, Utah,  801-773-4840, extension 1844
  • Wolcott Optical in Salt Lake City, Utah, 801- 485-4474