Our digital screens, fluorescent lighting, LEDs—they not only can cause pain (particularly for light-sensitive individuals), but they can lead to other visual symptoms like blurry vision. In fact, it is a pretty common experience for many of us to feel this discomfort at the end of a long work day under artificial light or after extended time on our devices. Our eyes struggle to focus, become irritated and our vision even starts to get cloudy or fuzzy.
And a primary reason this happens: exposure to light. Indeed, there is a clear link between lighting, light sensitivity and the onset of blurry vision. It can stem from the light source itself or even develop due to another condition, but regardless, it is often a big concern for patients.
Light Sensitivity and Blurry Vision: Possible Causes
Properties of various light sources
We have extensively discussed how the inherent characteristics of certain lighting can affect our eyes, and it is absolutely relevant to light-induced visual problems too. The following characteristics all can contribute to our eye-related symptoms:
- Ultraviolet (UV) light
- Visible and non-visible flicker
- Wavelengths of blue light
Fluorescent lighting is perhaps one of the biggest offenders when it comes to the harmful effects on our eyes. It is already well known to cause visual sensitivity in many people, but why do many also report that it makes their vision cloudy as well? One possible explanation revolves around the high concentration of ultraviolet (UV) light it emits. Evidence suggests that some fluorescent lights—mostly older models—operate outside the safe range for UV exposure; as a result, it might enhance the risk of eye diseases like macular degeneration and cataracts.1 Both of these are known to lead to visual symptoms like blurriness.
Visible and non-visible flickering is another mechanism necessary for lighting function (particularly for fluorescents and LEDs) but negative with respect to the eye problems it can cause.
LED lighting offers a more efficient way of producing light, but the constant flickering is believed to cause issues like blurred vision and light sensitivity, particularly when exposure times are high.2 Although fluorescent and LED lighting both can lead to similar symptoms, LED flicker may be even more nasty in its consequences because of the full spectrum dimming required to operate. This means they turn on and off hundreds of times per second. Here’s how leading light researcher Arnold Wilkins described it:
This description is consistent with similar experiences from other patients. One of the most common is the effect of car headlights at night. Directly staring into an LED headlight and then looking at another object creates what is called a ‘phantom array,’ or a blurry after-image that trails off behind the object. Dr. Wilkins directly argues that LED flicker is responsible for this temporary disturbance of vision, not glare or even brightness.3 And you do not have to be chronically sensitive to LED light to experience this blurriness in your eyes, although photophobia can absolutely make it worse.
Lastly, blue light is another instigator of the dual combo of light sensitivity and cloudy vision. LEDs, fluorescents, even sunlight produce a significant amount of these wavelengths. In studies of LED lighting, blue light exposure was shown to cause the pupils to constrict and lead to ocular deficiencies like blurry and double vision. It can also lead to temporary sensitivity to light for a healthy person and enhanced photophobia for an already-sensitive individual.
Other experts have added that children may be more vulnerable to the negative outcomes associated with blue light and flicker since they are generally more intolerant to it.3 But again, anybody can have these same physiological ramifications due to light exposure.
Onset of temporary visual syndromes
We live in a digital world, many times glued to our electronic devices for personal or professional reasons. Increases in multigenerational digital device usage have led to computer vision syndrome (CVS), also known as visual fatigue and digital eye strain (DES)—with the most common symptoms including blurred vision as well as eye fatigue and pain, headaches, dry eyes and neck/shoulder pain.4
And just how often does computer vision syndrome and eye strain result from our exposure to screen light? Here are a few incredible statistics:
- It is estimated that at least two-thirds—but perhaps as many as 90 percent—of computer users have visual symptoms (including blurred vision) after prolonged use.5
- Among a survey of hundreds of New York City office workers, one in five had blurry or clouded vision at least half of the time they worked on the computer. This affected both near and distance vision.4
It’s important to note that other factors may complicate and worsen the likelihood of blurry vision brought on by screen light exposure and sensitivity. For example, people with existing visual correction who need to wear glasses have a greater chance of dealing with this specific sensitivity.
Another key factor is the viewing and environmental conditions. The viewing distance from the screen and the duration of use also factors into the photophobia and blurry vision people might experience. Within an hour of use, people naturally reduce the distance at which they view their smartphone devices and also begin to experience the blurriness, eye fatigue and discomfort.6 This is a hallmark indicator of computer vision syndrome starting to manifest.
And of course we are all probably guilty of using our smartphones in darkened theaters, before bed or in other low light settings, but this behavior can damage our eyes too. In this darker setting, the brightness and blue wavelengths further strain our eyes and make it difficult to focus—thus leading to the development of blurred vision and ocular dryness or irritation.7
Presence of a light-sensitive condition
Light sensitivity can occur simultaneously with blurry vision and even function as a trigger for visual blur and other eye complications. Usually this is the result of a previously-diagnosed condition, of which several can lead to both symptoms.
Migraine with and without aura
Migraine has long been associated with visual disturbances like cloudiness of vision and photophobia—so much so that many have adopted the unofficial term "ocular migraine" as a type of headache disorder that directly strikes the eyes. Of course, these issues can occur before, during or after an attack, but generally those who experience an aura (approximately one-third of patients) have the greatest likelihood for blurry vision. And it is one of the most commonly cited eye-related issues, affecting between 25-54% of those with migraine aura.8,9 Of course, since light sensitivity co-occurs with migraine aura, then light exposure can similarly trigger or aggravate foggy vision.
Interestingly enough, these same disturbances may be regular occurrences for people who do not have a typical ‘headache’ phase and even for some that do not meet the diagnostic criteria for migraine.10
Concussion, post-concussion syndrome and TBI
The eyes are profoundly impacted after a head injury, which may be a direct result of the trauma or as an add-on problem from other ocular or neurological dysfunction. Fuzzy vision, double vision and light sensitivity are common complaints, regardless of severity. Moreover, they can have a negative impact on academic performance for children and even become a persistent problem when recovery is delayed.11 In fact, among post-concussion symptoms, visual blurriness hits about half of those with the disorder.
Further, it is well established that veterans with combat-related brain injuries may have longer recovery times and more intense physical problems—including blurred vision and sensitivity to light. In fact, those vets who went on to develop post-traumatic stress disorder (PTSD) self-reported these specific visual complaints at a higher rate than those without PTSD. Similarly, bright and artificial light exposure can sit at the center of it all, serving as an instigator of TBI-related blurry vision.
Dry eye disease
Dry eyes can represent temporary discomfort from a rough environment or from extended light exposure; for instance, looking at a computer screen for several hours can reduce your blink rate, which affects tear production and thus leads to ocular dryness and irritation. In addition, dry eyes can also signify a chronic problem for some patients that similarly have a set of triggers that can make symptoms worse. And guess what: persistent photophobia and cloudy or fuzzy vision are frequent side effects of the disease. In fact, about the same percentage of dry eye patients have one or both symptoms.12,13
Other ocular disorders can overlap with dry eye as well and share similar causes and therefore share symptoms. And light sensitivity is often one of the precursors to dry and irritated eyes, among other environmental triggers.
Most probably would not associate lyme disease with having extensive eye-relate symptoms, but they can definitely develop at any stage of the disease. More specifically, about 15% of lyme patients get either photophobia and/or visual focus problems, although those numbers are likely underreported.14 It is unclear exactly how often bright light exposure directly precipitates these ocular symptoms, but at minimum they are known to occur together on a regular basis.
Tips for relief
Dealing with these symptoms, especially both of them on a persistent basis, can lead to isolating feelings; after all, artificial light is everywhere and it can be difficult to escape it. But we want to emphasize that there are certain things you can do to improve the situation. Specifically:
- Get your eyes and brain checked: Seeing a physician and specialist can help identify any possible biological explanations for your experiences and lead to more targeted therapies for relief.
- Keep your eyes well lubricated: Even if you do not have dry eye disease, we all can feel dry or irritated eyes from light. Since visual blurriness is an after effect of dry eyes, it is important to keep them lubricated with artificial tears and other solutions.
- Be sure to wear your corrective glasses: One of the simplest tips to avoid eye strain is to make sure you wear your prescription glasses while looking at a screen or working under artificial light.
- Avoid light exposure in later-evening or low-light situations: While you may still experience blurry vision and photophobia in normal lighting conditions, the risk seems higher in dark environments because your eyes have to work harder to focus.
- Try tinted glasses designed for light sensitivity: TheraSpecs are a leading brand of custom-tinted glasses that improve photophobia, particularly when worn regularly around know triggers or during painful episodes.
- Take regular eye breaks: Spending hours under fluorescents or in front of a computer screen is a sure-fire way to bring on these problems, and giving your eyes a break every hour or so can limit the negative effects.
Hopefully, some of these suggestions can positively enhance the outcomes for you.
Without a doubt, being subjected to bright light—whether from fluorescents or screens—can create blurriness in the visual field. In addition, sensitivity to light often presents as a co-occurring symptom with cloudy or fuzzy vision, usually due to an underlying disorder like migraine or dry eye. And if you are one of these people that deals with light-triggered vision issues, there are some basic practices you can follow that can help improve it.
More Tips for Relief:
1Walls HL, Walls KL, Benke G. Eye disease resulting from increased use of fluorescent lighting as a climate change mitigation strategy. Am J Public Health. 2011;101(12):2222–2225. doi:10.2105/AJPH.2011.300246
2Batra S, et al. LED Lighting Flicker, Its Impact on Health and the Need to Minimise It. Journal of Clinical and Diagnostic Research. 2019;13(5):NE01-NE05.
3Lehman, B and Wilkins, AJ. Designing to Mitigate Effects of Flicker in LED Lighting: Reducing risks to health and safety. IEEE Power Electronics Magazine. 2014;1(3):18-26.
4Sheppard AL, Wolffsohn JS Digital eye strain: prevalence, measurement and amelioration BMJ Open Ophthalmology 2018;3:e000146.
5Rosenfield M. Computer vision syndrome: a review of ocular causes and potential treatments. Ophthalmic Physiol Opt. 2011 Sep;31(5):502-15. doi: 10.1111/j.1475-1313.2011.00834.x. Epub 2011 Apr 12.
6Long J, Cheung R, Duong S, Paynter R, Asper L. Viewing distance and eyestrain symptoms with prolonged viewing of smartphones. Clin Exp Optom. 2017 Mar;100(2):133-137. doi: 10.1111/cxo.12453. Epub 2016 Sep 8.
7Antona B, Barrio AR, Gascó A, et al. Symptoms associated with reading from a smartphone in conditions of light and dark. Appl Ergon. 2018 Apr;68:12-17.
8Petrusic I, Pavlovski V, Vucinic D, Jancic J. Features of migraine aura in teenagers. J Headache Pain. 2014;15(1):87. Published 2014 Dec 12. doi:10.1186/1129-2377-15-87
9Viana M, Tronvik EA, Do TP, et al. Clinical features of visual migraine aura: a systematic review. J Headache Pain. 2019 May 30;20(1):64. doi: 10.1186/s10194-019-1008-x.
10Wijman CA, Wolf PA, Kase CS, Kelly-Hayes M, Beiser AS. Migrainous visual accompaniments are not rare in late life: the Framingham Study. Stroke. 1998 Aug;29(8):1539-43.
11Swanson MW, Weise KK, Dreer LE, et al. Academic Difficulty and Vision Symptoms in Children with Concussion. Optom Vis Sci. 2017;94(1):60–67. doi:10.1097/OPX.0000000000000977
12Latkany R. Dry eyes: etiology and management. Curr Opin Ophthalmol. 2008 Jul;19(4):287-91. doi: 10.1097/ICU.0b013e3283023d4c.
13Barber L, Khodai O, Croley T, et al. Dry eye symptoms and impact on vision-related function across International Task Force guidelines severity levels in the United States. BMC Ophthalmol. 2018;18(1):260. Published 2018 Sep 29. doi:10.1186/s12886-018-0919-7
14Aucott JN, Rebman AW, Crowder LA, Kortte KB. Post-treatment Lyme disease syndrome symptomatology and the impact on life functioning: is there something here?. Qual Life Res. 2013;22(1):75–84. doi:10.1007/s11136-012-0126-6