We’ve all heard that blue light is harmful for our eyes and that we should avoid using screens at night in order to limit exposure to this harmful type of light, but what exactly is blue light and why is it so harmful?
What is blue light?
Blue light has the highest energy wavelength of all visible light and is located next to ultraviolet (UV) light on the visible light spectrum. Because blue light has such a high energy wavelength, it is able to penetrate through the protective filters of our eyes, reaching vulnerable parts of the eye such as the retina. However, there are two classifications of blue light, which vary in the amount of danger that they pose to the human eye. As explained in this video by SPY optics, while both types of blue light can occur naturally and/or artificially, long-wave blue light is beneficial for the body while short-wave blue light, also known as High-Energy Violet (HEV) light, can damage the skin and eyes.
What are the effects of blue light?
Some exposure to blue light is actually necessary for good health, and blue light has been shown to benefit memory and cognitive function. Blue light can also improve mood and is used in light therapy to treat seasonal affective disorder. Blue light also helps with alertness and regulation of the body’s circadian rhythm.
On the other hand, an excessive amount of short-wave blue light has been found to decrease melatonin production in the body, which affects the body’s natural sleep cycle. Excessive exposure to blue light can also cause dry eyes, digital eyestrain, and can even retina damage. Blue light exposure can also lead to more serious, long-term problems such as macular degeneration.
How can I protect my eyes from blue light?
So, what is the best way to avoid harmful blue light in your everyday life while also making sure that you don’t miss out on the benefits of long-wave blue light? There are several blue light filtering apps that can help reduce the amount of blue light emitted from electronic devices, but reading glasses or sunglasses with built-in HEV blocking lenses are great options for those who plan to be in front of screens all day. Lenses with blue-block coating offer an additional layer of filtering by removing harmful blue light rays from the light that makes it through the initial anti-reflective coating. Wondering if your current lenses offer blue light protection? Take this simple and quick test to see how effective your current lenses are at blocking blue light!