Tips to reduce digital eyestrain:
- Reading or computer glasses help reduce eyestrain
- Time flies: Set an alarm every 20 minutes of digital device time to complete the 20-20-20 exercise
- Move devices farther away from you – especially important for kids.
- Blink – and keep your eyes hydrated with preservative free artificial tears
- Avoid digital devices before bed
Dr. Mindy Blumberg
Computer vision syndrome is a type of eyestrain, headache, dry eyes, fatigue associated with computer use. It is common in our digital lives as adults spend an average of 11 hours per day watching screens. We are going to provide you with resources you need to decrease the visual symptoms associated with computer vision syndrome.
Computer vision syndrome is eyestrain caused by prolonged time spent on digital devices. Digital devices include phone, computer, and tablets. This eyestrain can cause headaches, dry eyes, blurred vision, double vision, reduced reading comprehension and fatigue. These symptoms are caused by excessive time your eyes are spending accommodating and converging. Accommodation is when your eyes must focus to see an object at near. Converging is when your eyes cross to get both eyes pointing at an object at near. When viewing in the distance your eyes get to relax accommodation and convergence, meaning that your eyes relax focus and uncross.
Computer vision syndrome can be prevented by using a variety of techniques. To relax your eyes from having to accommodate and converge for many hours there are a few techniques you can use.
The 20-20-20 rule is simple and easy. For every 20 minutes of focusing, you allow your eyes to relax by looking 20 feet away for 20 seconds.
Eyestrain can be relieved with reading or computer glasses. Glasses in the correct prescription can help reduce accommodative demand meaning it makes it easier for your eyes to focus on near devices. Reading glasses can also reduce convergence demand if needed by using prisms. Prisms change where the light is coming from so that more parallel light enters your eyes to reduce the ability of your eyes to cross and therefore reduce eyestrain. These glasses should be prescribed by your optometrist in order to get the best glasses for your lifestyle needs. A blue light anti-reflection coating will reduce the amount of blue light passing through the glasses and therefore will help reduce eyestrain.
To promote more relaxed visual experience, move your device further away. A longer distance between your eyes and the device reduces accommodation and convergence demand. When reading or using your phone the distance should be no closer than the length of your forearm (Harmon’s distance). When using a desktop computer, the farther away you move the screen the less your eyes must focus and cross to view it clearly.
Computer vision syndrome caused by dry eyes can be prevented by taking blink breaks. Surprisingly, some people may find that they blink less frequently and incompletely when working on digital devices. Blink breaks means taking a moment to fully blink your eyes to coat your eyes with tears in order to prevent dehydration. Artificial tears work well too, non preserved eyedrops with hyaluronate, or hyaluronic acid are proven to reduce dry eyes. Artificial tears typically only last up to 2 hours on the surface of the eye so use them regularly if you have severe dry eyes.
Dry eyes can also be improved by moving your screens lower so that your upper eyelids are partially covering your eyes. This can be beneficial to keep your eyes moist by a smaller surface area being exposed to the elements. A humidifier at your workstation may also be helpful.
Computers and digital devices emit blue light. Blue light has been a big debate as there are misconceptions. The sun regulates our sleep wake cycle, and the sun is the largest producer of blue light in our natural environment. In our eyes, there are cells called intrinsically photosensitive retinal ganglion cells (ipRGC) which absorb light and send information via the retinalhypothalamic tract to the suprachiasmatic nucleus of the hypothalamus in the brain. This area of the brain is responsible for the circadian rhythm or sleep wake cycle. When blue light is being absorbed by our bodies, melatonin is suppressed so that we feel awake. Melatonin is the hormone responsible for helping us fall asleep. Later in the day, after sunset, the blue light from the sun has disappeared so our bodies start producing melatonin to stimulate us to fall asleep. Therefore, nighttime use of computer screens, LED lights, LED TVs, and digital devices may be harmful to a good night’s sleep due to the blue light and lack of melatonin production. A blue light filter on screens is beneficial to regulate our natural circadian rhythm.
Digital devices are primarily a central vision task. The visual system has two primary pathways, the central vision pathway and the peripheral vision pathway. The central vision pathway also known as the ventral pathway is responsible for ‘what’ or object recognition. This central vision pathway is what is primarily used when focused on a near task. The peripheral vision pathway also known as the dorsal stream is responsible for ‘where’ or object positions in space.
Blue light is the shortest wavelength on the visual light spectrum. Blue light has a short wavelength of 400-450nm, red has the longest wavelength at 680-700nm. A shorter wavelength means that the light will focus in front of your retina, so your eye will focus and accommodate to bring the blue light in focus. Blue light is a short wavelength which means that your eye must accommodate to have clear vision. This is also partially why it is more difficult to see an LED clock with blue numbers instead of red numbers.
The effect of blue light on eye health is currently unknown. UV light is damaging to our skin and eyes and UV wavelengths are 290-400nm. Current evidence does not support blocking blue light for health reasons, however if we can consider UV exposure to be damaging to eye health maybe blue light could be damaging as well.
I recommend blue light filters (night lighting) on all digital devices. I also recommend blue light anti-reflection coatings on glasses for patients who spend over 2 hours per day on digital devices, patients who suffer from eyestrain when working on computers, patients who have post-concussion visual symptoms, and headaches or migraines with triggers associated to lighting. With these tips you can reduce computer vision syndrome to make your day more comfortable and productive.