Are you sensitive to light?
Does light trigger painful migraines or headaches? Is hiding in a dark room the only relief, or is something better out there?
Because not everyone shares this form of light discomfort, others may be inconsiderate to people with light sensitivity, or “photophobia”. People without this sensitivity cannot understand or imagine why anyone would find something as common as indoor lighting to be so offensive. Moreover, there is clearly a reason why some of us are more sensitive to light. Science is only beginning to understand the brain pathways that underlie photophobia.
What we know about light sensitivity:
Anyone who looks at the sun feels pain. It’s a protective mechanism that we share with all animals. The pain keeps us from damaging our eyes by exposing them to bright light; much in the same way that pain keeps us from touching something that’s hot or sharp. In light sensitivity sufferers, this protective mechanism is juiced up such that exposure to normal levels of light is painful.
It’s clear that some forms of light are more annoying to photophobia and migraine sufferers than others. Non-incandescent indoor lighting, especially fluorescent lights, can be especially irritating. The reason some of us don’t like these artificial lights is because the spectrum of light emitted is very different from the light that’s given off by the sun. You can see that the sun radiates the different colors of the spectrum in a relatively smooth curve that extends from red, to orange, yellow, green, blue, indigo, and violet:
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Incandescent lights, because they have a burning filament in them, also radiate a similar spectrum as the sun. However, fluorescent lights, LEDs, and gas discharge lamps, can have a much more “spikey” pattern of emission:
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In the above example, this particular artificial light emits in blue, yellow, orange, and red bands of the visible spectrum, but many of the other wavelengths are missing, giving the light an “unnatural” appearance. With fluorescent lights and LEDs in particular, strong emission occurs in the violet or blue parts of the spectrum.
Lighting manufacturers are working to improve the spectrum of fluorescent lights and LEDs to achieve a more pleasing color rendering index (CRI). When buying non-incandescent lighting, it may be better to choose bulbs with lower color temperatures (below 3000K), which are often confusingly called “warmer” colors.
Relief for Light Sensitivity:
Why not just wear sunglasses indoors? Most sunglasses make all colors of the spectrum dimmer, not just that portion of the spectrum that’s especially irritating. As a result, one must wear glasses that are fairly dark in order to get the desired effect. Unfortunately, by wearing dark glasses, even though one may feel better temporarily, once the glasses come off, the light sensitivity can become much worse! By wearing dark glasses, the eye “dark adapts” and becomes more sensitive to light. Think of what it’s like to go outside after being in a matinee for 2 hours. The afternoon light is blinding until your eyes re-adapt to the light.
A rose tint, called FL-41, was specifically engineered to help people with sensitivity to fluorescent light, partly due to the spectrum of emitted light and partly to the flickering fluorescent lights.
FL-41 is not a “cure”, it is only a treatment for light sensitivity, migraine, or blepharospasm, many sufferers have found it to be extremely helpful, enabling them to return to work, school, and church. Because it primarily blocks that portion of the visible spectrum that’s irritating, FL-41 tinted spectacles provide comfort without “dark-adapting” the eyes.