Blue light has grabbed a lot of attention recently, most of it negative. However, not many people seem to understand what blue light is, why it is supposed to be harmful, and if blue light filters make any difference.
What is Blue Light?
Blue light is one of the seven colours which make up the visible light spectrum.
The spectrum colours are often memorized by the acronym ROY G BIV. Each colour of the visible light spectrum has a different wavelength and level of energy. Of the seven, blue has the shortest wavelengths and highest energy. The sun is the most significant source of blue light, but fluorescent and LED (Light Emitting Diode) lights are also sources of blue light.
Why Do People Say that Blue Light is Harmful?
Blue light became the centre of studies linking eye damage and short-wave blue light. One study reported that blue light wavelengths between 415 and 455 nanometers could cause eye damage. Most of the light from computers, smartphones, TVs, and tablets has wavelengths between 400 and 490 nanometers. Hence the idea that blue light will harm our eyes. Optometrists, ophthalmologists, and researchers have not reached a consensus as to the degree of harm blue light from computers and smartphones causes.
Does Blue Light Cause Vision Problems?
There is not enough research on humans to directly conclude that blue light harms the eyes. Most of the data on blue light comes from animal research, which shows evidence that light can damage cells in the retina.
The degree of intensity is another point of interest in these studies. According to Andrew Anderson, an associate professor of optometry at the University of Melbourne. “The blue light from a computer screen is nothing even remotely close to the sorts of intensities required for it to cause damage.” However, many are quick to point out that because our LED devices are relatively new, there is not enough long-term research to say what impact blue light could have over a lifetime.
What Are the Other Eye Health Concerns?
A body of research does show that exposure to blue light may increase the occurrence of age-related macular degeneration (AMD), but the results are not definitive.
Studies show blue light can cause a condition called phototoxicity, which is damage to the retinas. Animal studies show that damage can occur over relatively short periods of exposure.
Blue light is often a contributing factor in cases of eye strain because of using computers and similar devices.
One study demonstrated that blue light triggered the release of toxic molecules in photoreceptor cells.
Ways to Protect Your Eyes
Reduce screen time to help limit exposure to blue light. If you must use a computer or other device, take regular breaks.
Anti-reflective lenses can increase contrast and reduce glare. They also block blue light from the sun and various computer devices.
Computer glasses are another option. These have yellow-tinted lenses that block blue light.
Blue light filters are available for most electronic devices and can reduce the amount of blue light given off by the screens.
How Does a Blue Light Filter Work?
Blue light filters are a convenient way of protecting your eyes from blue light emissions while you use computers, tablets, smartphones, and other similar devices.
The filters work by reducing the amount of high-energy visible blue light (HEV light) that reaches your eyes without changing your ability to see your screen.
The effectiveness of the blue light filter is closely tied to its blocking abilities. Studies on animals have shown that using a blue light filter that cuts 94 per cent of blue light can lessen damage from blue light exposure.
You can purchase blue light filters for electronic devices online and at electronic stores. Some are made of tempered glass to protect your screens as well as your eyes. Check for the amount of blue light the filter will block, and beware of cheap filters. Some filters will only block around 30 per cent of blue light, a nearly negligible amount.
Do Blue Light Glasses Work?
A product similar to blue light filters, blue light glasses are another way to protect yourself from blue light. Unlike the filters, which cover the screens of your electronic devices, the glasses will offer protection from other sources of blue light such as the sun or flat-screen televisions.
You do not need a prescription to get the blue light glasses that come without any vision correction. This popular type of blue light glasses in Australia is ideal if you wear contact lenses or if your vision needs no modification.
If you need corrective lenses for mild nearsightedness, farsightedness or astigmatism, your eye care professional can modify your prescription glasses. A coating is added to block the blue light to achieve blue light blocking. It will not impact the vision correction your eyeglasses provide.
For patients over 40 who usually wear glasses with progressive lenses or bifocals, eye doctors often recommend a pair of computer glasses. These are glasses with a single power lens and a blue light blocker. The glasses will correct your vision for up-close work at about arm’s length. It is vital that you only use these glasses when you are trying to see screens or another close-up viewing. These glasses will not provide you with any assistance with seeing things from long distances, such as driving.
Are There Other Kinds of Protective Coatings That Can Help Block Blue Light?
There are anti-reflective coatings for eyeglasses and computer glasses. Additionally, photochromic lenses provide UV and blue light protection indoors. Once you go outside, these lenses darken in sunlight, increasing comfort and reducing glare.
The Importance of Thorough Eye Exams and Eye Care
Medical professionals frequently say preventing a health problem is easier than correcting it. The statement is true for all branches of medicine, including eye care.
Visiting your eye doctor for regular checkups is key to the prevention, early detection, and treatment of numerous eye maladies, including those linked to blue light exposure.
Many people mistakenly believe that vision screenings are the equivalent of an eye examination. Vision screenings are assessments designed to find significant vision abnormalities. An eye exam is comprehensive and aimed at finding and treating significant eye disorders such as,
You can ask your eye doctor for more information about blue light glasses during your eye examination. It is possible to add the filter to your prescription eyeglasses, so you have consistent protection.
One of the best ways to ensure your eyes are healthy is to have regular comprehensive eye exams. E Eye Place has a friendly and experienced staff committed to providing the best care. If you would like to make an appointment or have questions about blue light glasses, feel free to contact us.
**Please Note** The material provided here is for informational use only. It is not binding medical advice and is not meant to replace an examination from a licensed doctor of optometry.
Stephanie is an owner optometrist, researcher and educator. She has held clinical, teaching and research roles in Australia and overseas, and has extensive training and clinical experience. Stephanie is also the head optometrist at E Eye Place, on top of this, she is also currently a PhD candidate at UNSW. Dr Stephanie Yeo Optometrist BOptom (HC1) GradCertOcTher DOPT (Merit) CO Ophthalmic Medicines Prescriber.