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Blue Light FAQ

Eyeglass Basics Guide 600x

Q: What is Blue Light?
All the light we see is a form of energy which is composed of tiny electromagnetic particles that travel in waves. This visible light is a spectrum of colors – each falling into a band of specific wavelengths. Blue light has a wavelength of between approximately 380nm and 500nm; making it one of the shortest, highest-energy wavelengths.

Q: How are we exposed to Blue Light?
Digital screen technology has advanced dramatically over the years, and many of today’s electronic devices use LED back-light technology to help enhance screen brightness and clarity. These LEDs emit very strong blue light waves. Cell phones, computers, tablets and flat-screen televisions are just among a few of the devices that use this technology. Because most of us are spending increasing amounts of time using digital devices, our exposure is increasing.

Q: What are the negative effects of Blue Light?
Blue light has both positive and potentially negative effects. On the beneficial side, it elevates mood and alertness. It has also been shown to boost memory and cognitive function as well as to help regulate our sleep/wake cycle (circadian rhythm). Its potential negatives, however, have been associated with digital eye strain, greater risk of certain types of cancers, diabetes, and heart disease. Increased exposure has been implicated in greater risk of age-related macular degeneration which can lead to permanent vision loss.

Q: How can we counter the negative effects?
While we cannot control all risk factors, proactively modifying common behaviors and using protective eyewear can help prevent eye strain and reduce exposure to high energy visible light. Here are some tips:
• Use dim red lights for night lights. Red light has the lowest effect on our sleep/wake cycle.
• Avoid looking at bright screens beginning two to three hours before bed.
• Expose yourself to lots of bright light during the day, which will boost your ability to sleep at night, as well as your mood and alertness during daylight.
• Take frequent breaks while working on computers.
• Remind yourself to blink frequently.
• Do not sit too close to your screen (aim for a minimum distance of 22 inches)
• Wear prescription or non- prescription protective ophthalmic glasses

Q: What can my optometrist do to help me in this area?
Your eye care provider will prescribe and design eyewear specific to your focusing and prescription needs. These special ophthalmic lenses will reflect the high energy blue wavelengths, thereby reducing penetration through the lenses and into your eyes.

Q: What is the relationship between Computer Vision Syndrome and Blue Light?
Because they are shorter, these “Blue” or High Energy Visible (HEV) wavelengths flicker more easily than longer, weaker wavelengths. This kind of flickering creates a glare that can reduce visual contrast and affect sharpness and clarity. This flickering and glaring may be one of the reasons for eyestrain, headaches, physical and mental fatigue caused by many hours sitting in front of a computer screen or other electronic device.

Q: What type of lenses / eyewear do you offer to combat the negative effects of Blue Light?
We combine a premium antireflection lens coat with a blue light filter unique to the manufacturer of the lenses we choose to prescribe in each case. This adds an extra absorptive filter to the lenses. We work with technology that can be tailored to indoor or outdoor light, or both.

Q: Anything else you wish to say about Blue Light and what your practice does in that area?
While media attention to this issue is just ramping up, we at Drs. Farkas, Kassalow, Resnick and Associates have been proactively prescribing and fabricating eyewear to protect against blue light exposure for the past few years. Given the frequency and duration of use of all sorts of visual devices by patients of all ages, we are recommending that your everyday eyewear, your computer glasses as well as any eyeglasses you wear over your contact lenses, offer this important measure of protection.