Blue Light Exposure: What Is It?

Blue light is produced naturally by the sun and generated by computer monitors, smartphone screens and other digital devices. Although the light has some beneficial effects, exposure can increase your eyestrain risk and even affect your central vision.

What Is Blue Light?

The rays of the sun may appear to be colorless, but they're actually made up of red, blue, orange, yellow, green and violet hues. Red and orange are located at one end of the visible light spectrum, while blue and violet are at the other. Red rays have long wavelengths, but produce less energy. At the other end of the spectrum, the wavelengths are shorter, but the energy is stronger. Because blue rays emit higher amounts of energy, they're more likely to affect your eyes.

Most of your exposure to blue light comes from the sun, but you can't avoid exposure simply by staying indoors. In addition to computer monitors and smartphones, blue light is produced by tablets, LED and fluorescent lights, LED light from TVs and compact fluorescent light bulbs. Although blue light plays an important role in maintaining the sleep/wake cycle, regulating your mood and keeping your memory sharp, it may harm your eyes.

Blue Light Exposure Can Cause Eyestrain

Have you ever experienced blurred vision, headaches or burning, itching eyes after spending hours in front of a digital screen? Long exposure to blue light may have been responsible for your symptoms. Blue light lowers the contrast on screens, causing the condition. Other factors that can contribute to eyestrain include poor lighting, failing to take regular breaks, less frequent blinking and dry air.

Central Vision May Be Affected by Blue Light

Long-term exposure to blue light may increase your risk of developing age-related macular degeneration (AMD). AMD occurs when the macula, the area of the retina responsible for central vision, is damaged. The condition is more likely to occur after age 60, according to the National Eye Institute, and is more common in Caucasians and people with a family history of the condition.

You may notice a blind spot or blurriness in your central vision if your macula is damaged by blue light exposure.When researchers studied 838 men who worked on the Chesapeake Bay in 1992, they discovered that the men with advanced AMD had higher exposure to blue light over the previous 20 years.

Your risk for AMD rises if you've recently had cataract surgery. Although your cataracts may have been a huge annoyance, they also prevented a large portion of blue light from reaching your retina. Once the cataract is removed, your exposure increases.

Israeli researchers noted an increase in photodynamic therapy used to treat the wet form of macular degeneration in people who had cataract surgery. Their study, published in the February 2007 issue of Ophthalmology, discovered significant increases in the therapy at both six months and one to 1 1/2 years after surgery.

Protecting Your Eyes from Blue Light

Following these tips can help protect your eyes from AMD:

Buy a Filter. Adding a blue light filter to your screens can improve contrast and lower the amount of blue light that your eyes absorb.
Take Breaks: Taking frequent breaks from your computer, tablet or smartphone helps lower your blue light exposure and also gives your eyes a chance to rest. Breaks don't have to be long. If your day is hectic, simply looking away from your computer for a minute or two every 20 minutes can be helpful. When you take a longer break, avoid screens completely. Checking your smartphone after working on your computer doesn't count as a break.
Try New Glasses. If you spend much of your day working on a computer, you may want to consider buying a pair of prescription computer glasses. The glasses block blue light, improve contrast and help reduce eyestrain.
Consider Blue Light-Blocking Lenses After Cataract Surgery. Special lenses that reduce blue light transmission can be used in place of clear lenses after your cataract surgery.

Are you concerned about the effect of blue light on your eyes? Regular eye examinations and glasses that offer blue light protection can help you protect your eyes. Call us today to schedule your next appointment.

Sources:

AllAboutVision: Blue Light: It’s Both Bad and Good for You, 2/17

http://www.allaboutvision.com/cvs/blue-light.htm

PubMed: Archives of Ophthalmology: The Long-Term Effects of Visible Light on the Eye, 1/92

https://www.ncbi.nlm.nih.gov/pubmed/1731731

National Eye Institute: Facts About Age-Related Macular Degeneration

https://nei.nih.gov/health/maculardegen/armd_facts

Ophthalmology: Cataract Surgery is Associated with a Higher Rate of Photodynamic Therapy for Age-Related Macular Degeneration, 2/07

http://www.academia.edu/17812980/Cataract_Surgery_Is_Associated_with_a_Higher_Rate_of_Photodynamic_Therapy_for_Age-Related_Macular_Degeneration

Prevent Blindness: Blue Light and Your Eyes

http://www.preventblindness.org/blue-light-and-your-eyes

Review of Optometry: The Lowdown on Blue Light: Good vs. Bad, and Its Connection to AMD, 2/14