Kenton Optometrists Blog

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Screen time and blue light

How to protect your eye against blue light?

Have you ever found yourself with a headache and unable to sleep after a day in front of the computer? Many people are in front of a screen all day, protecting ourselves from blue light exposure is becoming more important.

Studies show that the average adult spends more time each day staring at screens than sleeping. It is easy to spend the whole day in front of a screen without realising the damage it is doing to your eyes. This is especially the case when using multiple devices such as phones, tablets and laptops.

So, what is blue light? All visible colours are used to make up white light; however, those at the blue end of that range can be harmful to our eyes. Screens produce high levels of blue light, and this can lead to eye strain and long-term damage to your eyesight.

These 5 Simple ways can help protect your eyes from blue light.


1. Screen Protection

While spectacles may not be needed specifically for distance or near activities, you may find that spectacles prescribed specifically for digital screen use can be helpful.

This applies to younger individuals as well, and not just people with presbyopia. In fact, a quite common problem amongst a large number of short-sighted individuals is that their distance spectacles, whilst giving reasonably good distance vision, causes specific difficulty for near work. Thus, by making some slight adjustments to the distance prescription can go a long way in promoting comfort for screen use. 

Special coatings like Anti-glare and Blue Protect on the lenses are also helpful to maximize comfort and vision. Anti-glare spectacles help improve contrast with the digital screens by reducing the amount of light reflecting off the front and back surfaces of your lenses. Individuals who do not actually have any spectacle prescription may also find it more comfortable to be using a pair of anti-glare lenses and Blue Protection spectacles.


2. Proper lighting

Eye strain often is caused by excessively bright light, for example from sunlight through a window or from excessively bright interior lighting. Determining how much is too much is sometimes a matter of trial and error.

Ideally, computer screens should be positioned such that they are not near windows with sunlight streaming in, or with bright sunlight behind them, causing discomfort as some computer screens are reflective.


3. Ergonomics

As surprising it may be, the positions of your computer screen, reference materials, and seating position all do matter.

Most people find it more comfortable to view a screen whilst looking slightly downward. The optimal position of the computer screen should be about 10 to 15 degrees below eye level, which is about 7 to 10 centimetres from the centre of the screen and the screen should be 50 to 70 centimetres from your eyes.

Trial and error usually gives the optimal distance for ease of viewing and to avoid excessive head movements which can tire you out and sometimes result in a sore neck. If possible, reference materials can be placed at about the same eye level on a document stand.

Chair height settings should therefore take into consideration these requirements, as well as the need to allow the arm and wrist to rest comfortably for keyboard usage.


4. Display settings

Firstly, adjust the display settings of your computer, which can help to keep your eyes comfortable.

Secondly, adjust the brightness of the display, so it is approximately the same as the brightness of your surroundings. This reduces wide variations in the contrast between your surroundings and your screen, which make it more difficult for prolonged reading work.

Finally, adjust the text size and contrast, especially for long articles. Also, black print on a white background is the best combination to facilitate reading.


5. Rest and blink

To prevent eye strain, try to rest your eyes when using the computer for long periods. Rest your eyes for 15 minutes after about one or two hours of continuous computer use simply by closing them. Closing the eyes allows your eyelids to bring a good layer of tears to moisten your cornea.

A good rule of thumb is to rest your eyes after every 20 minutes of computer viewing by looking into the distance for 20 seconds to allow your eyes a chance to refocus. Do this for about 10 times.

A good habit is to blink frequently. With prolonged screen time, we often forget to blink, and so conscious effort is necessary. Blinking has a milking effect on the expression of oil from the eyelid glands into the tear film, which coats the cornea with a nice layer of tears.