Blue Light & Digital Eyestrain


Experiencing eye strain and headaches when looking at electronic devices? You may have computer vision syndrome (CVS). Especially now during COVID-19 pandemic, many of us are working from home in front of our computers and devices.


What is Computer Vision Syndrome?


Computer Vision Syndrome (CVS), also referred to as Digital Eye Strain, is an umbrella term for eye- and vision-related conditions caused by prolonged usage of digital devices such as computer, smartphones, ipads, and e-book readers


What are the symptoms?

The most common symptoms associated with CVS are:

  • Eyestrain.
  • Headaches.
  • Blurred vision.
  • Dry eyes.
  • Neck and shoulder pain.




  • Improper lighting.
  • Improper viewing distances
  • Glare on a digital screen.
  • Poor sitting posture.
  • Uncorrected vision problems.
  • A combination of these factors.


What is blue light?


Sunlight is made up of red, orange, yellow, green, blue, indigo, and violet light. These lights have different wavelengths and energy, and when combined, it becomes the white light we see. Computers and digital devices are, as sources of light, also contain blue light

Blue light produces high energy. Exposure to blue light has its own benefits during daylight hours because it has been found to boost attention, reaction times, and mood. However, due to its nature, blue light flickers easier and longer than other types of weaker lights, and therefore casts a glare that reduces your visual contrast, affecting clarity and sharpness.

For the urban lifestyle, where we spend a significant amount of time using computers and digital devices, prolonged exposure to blue light can cause digital eyestrain and, sometimes, long-term vision damages. In fact, a survey released by the Vision Council suggests that 43% of adults have a job that requires prolonged use of a tablet or computer, while 70% of adults that regularly use electronic devices report symptoms of digital eye strain.



Digital eye strain or CVS, can be diagnosed through a comprehensive eye examination, with special emphasis on the usage of computers and digital devices, may include:

Patient history to determine any symptoms the patient is experiencing and the presence of any general health problems, medications taken, or environmental factors that may be contributing to the symptoms related to computer use.

Visual acuity measurements to assess the extent to which vision may be affected.

A refraction to determine the appropriate lens power needed to compensate for any refractive errors (nearsightedness, farsightedness, or astigmatism).

Testing how the eyes focus, move, and work together. In order to obtain a clear, single image of what is being viewed, the eyes must effectively change focus, move and work in unison. This testing will look for problems that keep the eyes from focusing effectively or make it difficult to use both eyes together.


In some cases, such as when some of the eyes’ focusing power may be hidden, eye drops may be used to temporarily keep the eyes from changing focus while testing is done. Using the information obtained from these tests, along with the results of other tests, an optometrist can determine the presence of CVS or digital eyestrain and advise treatment options.




1. Computer viewing position


The Canadian Center for Occupational Health and Safety (CCOHS) suggests that viewing angle and viewing distance are the most important factors to proper computer viewing position:

Viewing angle refers to the degree above or below an imaginary horizontal line at the level of the viewer’s eyes and the center of the screen, which should be between 15-30 degrees (see Figure 1).

Viewing distance refers to the space between the operator’s eyes and the screen, which should be between 40-70cm or 16 – 28in (see Figure 1). A poor angle leads to postural (neck and shoulders) discomfort, while the wrong distance can contribute to eyestrain.


2. Lighting


Poor lighting affects not only the ocular system but can also contribute to stiff necks and aches in the shoulder area. These problems can occur when people adopt poor or awkward postures when trying to read something under poor lighting conditions.

A good visual environment will:

Have sufficient light, coming from the right direction and not cause obscuring shadows.

Provide good (but not excessive) contrast between the task and the background.

Limit glare and extreme contrasts.


Position the computer screen to avoid glare, particularly from overhead lighting or windows. Use blinds or drapes on windows and replace the light bulbs in desk lamps with bulbs of lower wattage. If there is no way to minimize glare from light sources, consider using a screen glare filter. These filters decrease the amount of light reflected from the screen. To minimize the chances of developing dry eye when using a computer, try to blink frequently. Blinking keeps the front surface of the eye moist.


3. Blue Light filter glasses!


The concern about blue light exposure and its consequences on our vision has long been acknowledged by the eyecare industry. There are various technologies developed by reputable lens manufacturers in Canada to help users of computer and digital devices combat this issue with premium quality.

Some of the best blue-light filter technologies we provide at Saigon-Eyelike Optical include:

  • Choice BluSelect – by Kodak Lens

CHOICE BluSelect lenses block 100% of UV light and filter blue light to protect your eyes from the harmful effects of the blue-violet light spectrum. How? The lens material feature works on the principle of absorption and has embedded protection that is built into the lens to reduce harmful blue light exposure.

  • Crizal Prevencia – by Essilor

Crizal Prevencia lenses reduce exposure to harmful Blue Light while still allowing beneficial blue-turquoise light to pass through. Plus, they provide all the benefits of no-glare lenses and help protect your eyes from blue-violet light. They are suitable for those with a family history or exhibiting signs of age related macular degeneration, and working professionals, children, teens, and gamers.

  • SeeCoat Blue coatings – by Nikon

With the same purpose, Nikon developed and updated their SeeCoat Blue coatings with add-ons appealing benefits that are unique to their lenses. Lenses with SeeCoat Blue coatings provide high contrast by cutting blue light and optimizing transparency. They are 2 times more scratch-resistant and have longer durability. They also resist the accumulation of dust and are easier to clean.