Ah, the good old days when Mum said your eyes will turn into squares if you sat too close to the TV… What if, that was sort of true? Will sitting too close cause you to go blind?

Mopani Pharmacy had a chat with optometrist Dave Kenyon on how to optimise your screen time safely, with the least strain on your eyes.

About those square eyes…


Obviously, your eyes will not turn into squares. However, the myth came from somewhere, right? Old TV’s used to be squares. Now, most people love watching TV in the dark. Horror movies are more intense, there are no distractions and the contrast of the bright screen in the dark is awesome!

“Generally, a dark room with a bright TV will bleach a square on the back of the eye. It is important to have a soft light at least behind the screen, so without knowing it, your eyes are not so fixed on the screen”, Dave explained.

Sitting too close to the screen?

With a TV screen you can probably use your discretion, but a computer screen may be tricky.

“With a laptop screen you can sit around 40cm away from the screen. With a large computer screen, you can sit about 70cm away. Some gamers have huge screens, they can sit three meters away and still see everything!” said Dave.

Dedicated computer glasses

You can invest in a dedicated computer lens as well; just make sure to measure the distance to your screen before your appointment at the optometrist – but how do they work?

“The strength of the lens varies according to the distance away from the screen, as does the focal length. The latest accepted advice on computers is the 20/20/20 rule. Work for 20 minutes, then for 20 seconds try and look at 20ft (6 meters to us) in front of you. And remember, the rest does not mean looking at your cell phone!” Dave explained.


With computers, posture is very important. As we’ve mentioned, in a previous article, there are a few things you can do to adjust for a healthy posture. Your back and neck will thank you, but what about your eyes?

“Your eyes adjust with your movement and surroundings. The area around you may reflect light off your screen, or you are catching something from the side of your eye. The screen should be straight in front of you if you want to work efficiently. As soon as your eyes have to compensate for a vertical change, they will also tire quicker”, Dave explained.

“If you happen to use multi-focal glasses, your eyes will need to adjust between the bottom part of the lens for your keyboard use that may be close, and upward for your screen. Make sure that your screen is around eye-level, so you don’t need to physically lift your head to see it”, Dave explained, “This way your computer use won’t be such a pain in the neck!”

Eye dryness and fatigue

“Adjust the brightness to a comfortable level and be aware that if you concentrate you may forget to blink. Make sure that you blink properly with full lid closure,” said Dave. As mentioned before, it is important to look away from the screen every 20 minutes or so.

Will my eyes get lazy if I wear spectacles?


“The greatest myth about vision is the belief that wearing spectacles will make your eyes weaker. Without specs, something blurry far is just too far if you are short-sighted. Put your specs on and wow, I can see. Remove them later and you will suddenly realise that you cannot see. The same goes for readers. One factor is discernment of a blur. You get used to seeing shapes and making a decision. A bit like birding – an experienced birder will tell you the type of bird, whilst you only see a little brown dot! It is in the way they landed on a branch, they say. With specs you can see the details that you otherwise could not” Dave explained 

So, when you are over 42, you start holding things further away. You avoid reading in your favourite armchair in the poorly lit corner of the living room. Don’t even bother reading the fine print or the prices in the shops! Cheaper than buying readers, is the common reason…

Eventually you realise that you have to get your glasses and voila, the world is a brighter and clearer place, until you lose or break them!

“Time has marched on and unfortunately, accommodation reduces with age, so life is a bit of a blur because your eyes have weakened – not due to the specs, but because you are older, and because you got used to the clear vision. I guess it shows how much you do need them”, Dave explained.

What if I just buy a pair of reading glasses?

“Off the shelf readers are not harmful to your eyes as such. The main problem is that an eye test is avoided that could potentially identify a disease or problem that could result in blindness or loss of the majority of your vision. Eye tests can also identify other chronic conditions such as diabetes and cataracts”, said Dave.

“For general purposes, if your eyes are not too close together or too far apart readers are a starting point. Optical centres in your eyes play a major role in causing or reducing eyestrain.  If you are aware of your ocular health, and if both eyes see perfectly far, then readers are fine for the over 40’s” he explained.



If you would like to consult Dave on your eye health and have an eye-examination done, you can book an appointment on 013 755 2276. His practice is located at Crossing Centre, near the pet store.

We have a large range of eye-care products, reading spectacles and supplements available at Mopani Pharmacy. If you need help choosing the correct product for you, have a chat with our pharmacists or knowledgeable sales staff.

We can deliver your supplements and other Mopani online shopping, nationwide! Contact us for info: mopani.co.za | crossing@mopani.co.za | Tel: 013 755 5500 | WhatsApp: 066-192-1703