Blue Blocker Lenses and Beating the Blue Light Blues

Blue Blocker Lenses and Beating the Blue Light Blues

You are exposed to all kinds of light and other forms of electromagnetic radiation everyday from sources such as sunlight, fluorescent lights, computers, laptops, smartphones, and TV.

What is Blue-Violet Light?

Blue-violet light is the most energetic out of all the light that can be seen by the human eye, also known as the visible spectrum. You already know the visible spectrum if you can name the colours of the rainbow (hint: ROYGBIV).

What Makes Blue Light Different?

Blue-violet light has the highest energy because it has the shortest wavelength on the electromagnetic spectrum because energy and wavelength are inversely related. That means the shorter the wavelength, the higher the energy and vice versa.  The wavelengths of the visible spectrum range from approximately 400-700 nanometers (nm).

So red light, at around 700 nm, has the least energy and blue light, at around 400 nm, has the most.

What is Ultraviolet Light?

Even more powerful than Blue-Violet light is Ultraviolet Light, X-Rays, and Gamma Rays. Ultraviolet light, also known as UV light, is invisible to the human eye and can cause cancer! It’s the reason why we wear sunblock and sunglasses when we’re out in the sun and its wavelengths range from around 10-380 nm.

The Good

Ever notice how a little sunshine can improve your mood? That’s because moderate exposure to certain types of blue light is essential to your well-being, and along with elevating your mood, it can make you feel more alert and even help with memory. Blue light exposure also keeps your biological clock ticking on time – one of the biggest sources of blue light is the sun, and when it sets, your body takes the hint that it’s time to start getting ready for sleep.

What we call light is only a small range on the spectrum of electromagnetic radiation, which also includes radio waves, microwaves, ultraviolet rays, X-rays, and gamma rays. (Images provided by Dr. Shaun Pati)

The Bad

Prolonged and constant exposure to blue light can cause your eyes discomfort such as strain and glare. Also, since blue light is important in regulating our circadian rhythms by letting our body’s natural clock know when it’s time to sleep, too much blue light exposure right before bed will negatively affect the quality of your sleep and can make you feel more tired and less alert the next day. This is becoming an increasing issue as some of the main sources of blue light (aside from the sun) are our electronic devices (such as your smartphone, notebook, TV, and computer). That’s why you should think twice about using your phone and computer right before bed!

The Ugly

Blue light exposure puts you at increased risk of Age-Related Macular Degeneration, especially for people over the age of 50. This condition, which affects the part of the retina known as the macula, is non-curable and affects the sharpness and clarity of your central vision, which you depend on to drive and read. Too much exposure to UV light can cause cataracts and even temporary blindness (known as photokeratitis) due to sunburns on the cornea. Just another reason why you should NEVER stare directly at the sun!

What Can You do?

You can’t (and shouldn’t) try to avoid all blue light, but instead take steps to reduce your exposure. This can take on many forms- from reducing your time staring at a screen (especially right before bed), to using blue blocking filters and lenses. At Real Eyes Optometry, we recommend using Crizal Prevencia No Glare lenses which not only blocks harmful blue light (while letting the good blue light through), it also offers comprehensive UV protection.

If you use Sun block for your skin, you should use Blue block for your eyes. It’s that simple.

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