The biggest part of an average work day is spent behind the computer. During the COVID-19 pandemic, our screen time has increased even more with video calling, online meetings, and webinars. It takes a toll on our muscles, eyes, and eventually affects our productivity. BETTER VISION gives tips and information on glasses for computers, and preventive measures for computer vision syndrome (CSV).
The term computer vision syndrome (CSV) is used to describe problems that result from prolonged computer, tablet, e-reader and smartphone use. It’s also referred to as digital eye strain (DES), because the symptoms are not limited to time spent at computers.
When you use any digital device, it places a unique demand on your eyes, different to any other visual activity. You have to either focus at a screen for a long time on end, or change your gaze between a device such as your phone or a tablet and the environment around you. It can place strain on the eyes, making it harder to accommodate (changing your focus between different distances). For this reason, people who use digital devices a lot, often experience vision- and posture-related problems.
According to the American Optometric Association, the most common symptoms of DES are eyestrain, headaches, blurred vision, and dry or burning eyes, as well as neck and shoulder pain.1 Of course, if you’re older than 40, accommodation problems may also be a result of the gradual loss of the ability to focus on nearby objects that comes with aging (presbyopia). A lot of screen time can worsen the discomfort even more.
With more and more people working from home, having a proper, dedicated space for a home office has become very important. An ergonomic sitting posture at the screen and the right glasses prescription can improve comfort and vision at a computer work station.
Chair and desk
A new chair or even just an adjustment of the chair settings can often help make work less straining. Make sure that the natural curve of your lower back is supported by your chair, so you can comfortably keep your upper back straight.
As a rule of thumb, you should be able to fit a fist between the top of your thighs and the bottom of your desk. If there’s no space between your legs and the desk, your desk is too low and you should either adjust your chair or make the desk a little higher by propping it up on blocks or books. If there’s too much space between the desk and your legs, adjust the chair so it’s a little higher.
Make sure that your feet are flat on the ground, and that your legs form a 90º angle with your body. If you’re short, try a footrest to see if it improves your sitting position.
Screen and keyboard
Make sure that your screen has the highest possible refresh rate and image stability. Adjust your monitor so that the picture is rich in contrast and sharp. Also adjust the font size so that you can read the text easily and comfortably.
The top of the screen should be slightly below horizontal eye level, and about 50 cm away from your eyes. Test the distance so it’s more or less an arm’s length.
Getting the right distance and height can be a bit harder with laptops. Adding on external elements that you can plug into your laptop such as a mouse, keyboard and monitor can up the comfort. There are also various ergonomic laptop stands that can be adjusted to a comfortable reading and typing height, and a lot of these can also fold flat so you can take it with you wherever you go.
When setting up your keyboard, you should be able to rest your forearms or elbows on your chair armrests while typing, without having to hunch your shoulders. The same goes for using a trackpad or mouse.
If you’re constantly experiencing symptoms of DES, it’s important to go for an eye test, or update your current glasses prescription. It’s possible that you simply have an unaddressed refractive error, and the right lenses may correct this and improve your perceived eye strain.
You may find that a new pair of glasses can actually improve the way you work, as research shows that uncorrected refractive errors actually has an impact on economic productivity.2
When your regular prescription or reading glasses don’t improve eye strain, it may be time to consider computer glasses.
Single vision or progressive lenses are generally not optimised for office work. Reading glasses enable optimum vision that’s too close for computer work. Progressive lenses require that you look through the lower area of the lens, so you will unnaturally tilt your head upwards to see the screen. If you wear these types of lenses for office work, chances are good that you’re sitting in an unnatural position, leading to headache and muscle tension.
Your eyes need support in the intermediate zone when you work at a desk on a daily basis. This refers to the distance more or less where your screen is positioned. It’s a little further away than near vision (a book or checking your phone), and closer than distance vision (looking at something far in the distance or driving). When we focus at this distance for an extended time, our eyes tend to converge, and this can be quite tiring for the eye muscles.
Computer glasses are optimised for the intermediate viewing zone. In addition, it can correct any additional refractive errors you may have, such as presbyopia or astigmatism with an individualised prescription.
What to look for when buying computer glasses
- How will you use your computer glasses?
As you will see here, there are different types of computer glasses. It’s important to discuss with your eyecare professional exactly what you will be using your glasses for, so your prescription can be tailored to meet your needs.
- Refraction, fitting and centration
The more exact these processes are, the faster you will adapt to your new lenses. Ensure that you consult a reputable eyecare professional who prescribes lenses from a trusted supplier.
- Anti-glare coating
Anti-glare or anti-reflective (AR) coatings are applied to the lenses to eliminate irritating reflections from the front and back of the lenses. Vision challenges like glare or reflections can decrease the wearer’s vision comfort and may contribute to the symptoms of DES. Discuss your options of anti-glare glasses for computers with your eyecare professional.
Some blue light filter glasses produce a visible blue/purple reflex. This is especially evident during video calls, and it is usually the case with blue light coatings applied to the lens surface. If appearance is high on your list, rather look for lenses with in-material blue light technology, such as ZEISS BlueGuard Lenses. The blue light protection is incorporated into the lens itself, so visible reflections are minimised.
There are different lenses for computer glasses to choose from, depending on the visual requirements of your job.
Generally, there are three types of office setups:
- An indoor workstation with a computer, and some contact with other staff.
- An indoor workstation where the person reads a lot of printed material and looks at sketches (for example architects).
- An indoor office setup with a lot of contact with other staff and customers, as well as some computer work.
With this design, you’ll have natural vision from a closeup reading distance, up to two metres. It’s ideal for intense computer work and reading.
Comfortable vision ranges from a closeup reading distance to a typical room distance of around four metres. It’s ideal if you work at a computer and interact with customers, as you don’t have to take off your spectacles when getting up from your desk and walking around.
These lenses have a maximum distance of one metre, but compared to reading glasses, it will give you a significantly larger field of vision for a comfortable reading experience.
These computer lenses are completely tailored to your personal needs. The viewing distance is customised to the nearest centimetre, and frame data, face shape as well as near working distance is incorporated into the design.
Visible light is the portion of the electromagnetic spectrum that is visible to the human eye. A portion of this visible light falls in the blue/violet band, and is described as high energy visible light (HEV). The sun is the brightest source of blue light. A part of the blue light spectrum is good for us during the daytime, as it boosts attention, mood and reaction time.
Modern digital devices such as smartphones, televisions, computer monitors, e-readers and tablets emit blue light. Even energy saving LED bulbs emit blue light.
At night, overexposure to blue light can affect the body’s circadian rhythm, leading to sleeplessness and fatigue.
The human eye can’t block blue light. In fact, all visible blue light passes through the lens and cornea, ultimately reaching the retina. If you spend a lot of time working on digital devices, you may perceive eyestrain and blurred vision. Too much nighttime blue light exposure can also make it difficult to sleep and exacerbate patterns of insomnia.
It’s important to note that not all computer glasses are blue light blocking glasses. Spectacles for computers are simply designed to improve vision comfort in the intermediate zone, and it doesn’t necessarily feature blue light protective qualities.
However, you can customise your computer lenses or any other glasses lenses with a specialised blue light coating. Such coatings are applied to lenses, and include a blue filter which lessens blue light. It will improve your visual comfort, without losing out on its beneficial effects.
- Take breaks
Get up from your desk whenever you get a chance and go for a quick walk. Fetch a glass of water or make a cup of coffee or tea, just to ensure you give your eyes a rest and that your body doesn’t remain in the same position for too long.
- Rest your eyes
The 20-20-20 rule applies here. Every 20 minutes, look into the distance at least 20 metres away, for at least 20 seconds. This will ensure less eyestrain from focusing in the intermediate zone all the time.
- Blink often
We tend to forget to blink when working on digital devices. Blink deep and hard whenever you remember to, and when you take breaks also make a conscious effort to blink. This will lubricate your eyes and improve symptoms of dry eyes.
- Take care when setting up your workstation
Follow these guidelines when setting up your workstation.
- Exercise and stretch
Try to exercise or walk at least three times a week, and stretch your sore and tired muscles throughout the day. Add on a 10 minute stretching session after a particularly long day’s work.
Speak to your eyecare professional if you perceive increased strain, dryness and blurry vision from devices that emit blue light.