Blue light: What is it all about?
Throughout our day, whether at home, work or being outdoors, we are exposed to a variety of visible and sometimes invisible light rays that can have an effect on our eyes.
The sunlight or “white light” we see is a combination of visible colored light rays that contains red, orange, yellow, green and blue light rays. All of these light rays have energy and a wavelength. It is also called the electromagnetic spectrum.
Electromagnetic rays beyond the red end of the Visible Light spectrum are called infrared. The heat we feel from sunlight, a fire, a radiator or warm sidewalk is infrared. On the opposite side of the visible light spectrum we find the highest energy. This is why the electromagnetic rays beyond the blue-violet or violet light are called ultraviolet (UV) radiation.
Ever wondered where your suntan came from? Moderate amounts of UV radiation help the body to manufacture adequate amounts of vitamin D. Too much exposure to this invisible UV radiation can cause skin cancer or sunburned eyes (a condition called photokeratitis or snow blindness, affecting the cornea)
Because of the short-wavelength, high energy visible (HEV) rays on the blue end of the visible light spectrum scatter more easily, than other visible light rays, when they strike air and water molecules in the atmosphere and that is what makes the cloudless sky look blue.
Natural blue light exposure is essential for good health. Research has shown that high-energy blue light, during daytime, boosts alertness, cognitive function, helps memory and elevates mood. The body also uses this exposure to regulate our wake and sleep cycle, known as our circadian rhythm.
Artificial blue light comes from digital screens although it appears “white”, like TVs, smart phones, gaming stations, computers, laptops and tablets, even fluorescent and LED lighting. Because of these shorter blue wavelengths it flickers more easily than longer wavelengths and it creates a glare that can reduce visual contrast and affects sharpness and clarity.
This flickering may be one of the reasons for headaches and eyestrain. Too much of this blue light exposure late at night can disrupt our circadian rhythm and potentially cause sleeplessness and daytime fatigue.
Blue light filters are a convenient way to reduce blue light exposure. If you aren’t wearing glasses there are screen filters available for your devices. Some are tempered glass that also protects your device’s screen from scratches.
With prescription glasses there are coatings that act as a blue light filter that protects against the harmful effects of UV rays and blue-violet light. You can also consider photochromic lenses, when we’re constantly alternating from indoor and outdoor activities, protecting your eyes from UV rays and glare of the sun.
What about outdoor activities like hiking, mountain biking or just a visit to the park? Polarized lenses not only reduce glare, they make images appear sharper and clearer, increasing visual clarity and comfort
Protect your eyes! Contact us for advice on these options.