Ah! Gone are the days of reading the good old Joystick Magazine sitting on the rim of the toilet . Like our co-founder Paul, many prefer to read their favorite authors on tablets or e-readers.

We understand, it has many advantages. But do you know if this extraordinary reading tool emits blue light? Is it dangerous for your eyes? It depends ! We explain everything to you in detail.

In this article :

  • What is blue light?
  • Blue light: what are the dangers?
  • Reading lights and blue light: what you need to know
  • Solutions to avoid blue light from e-readers
  • [BONUS: choice of reader with blue light filter]

What is blue light?

Light is made up of electromagnetic particles that travel in waves. So far nothing complicated.

Woman reading her kindle paperwhite e-reader

These waves emit energy and vary in length and intensity. For example, the shorter the length of this wave, the higher the energy will be.

Each wavelength represents a different color and is grouped into categories: gamma rays, X-rays, ultraviolet (UV) rays, visible light, infrared light and radio waves .

🌈 These wavelengths constitute what is called the electromagnetic spectrum.

Are you still with us?

The human eye is sensitive to only one part of this spectrum: visible light. – Kind of like vampires, you know?

This part of the spectrum is split into colors, ranging from purple, indigo, blue, green, yellow, orange to red – it reminds us of Power Rangers, but it's not exactly the same.

So-called blue light has a very short length and therefore projects a large amount of energy. ⚡

Where is blue light found?

Blue light is everywhere, since sunlight contains this wave – from the electromagnetic spectrum. It is necessary for good health but the more you get closer to purple and the more it is intense and that is the problem.

Kindle stored with other books in a bookcase

Since the democratization of digital devices, many other sources of blue light added to that of the sun . We are talking about the brightness of digital screens (computers, tablets, TVs, and smartphones), in addition to other electronic devices or fluorescent or LED lighting.

Blue light: what are the dangers?

The evolution of digital display technology has advanced considerably over the past two decades. The vast majority of electronic devices we use feature high-tech LED backlighting .

This technology emits high intensity blue light waves. Phones, our computer screens, flat screen televisions, tablets and e-readers use this type of lighting.

Kindle e-reader on a table next to a cup of coffee

Our daily use of these machines increases our exposure to blue light and this over longer and longer periods – and yes, if we played the PS4 a little less, we wouldn't be there!).

Many studies confirm that over time, exposure to this spectrum light can cause serious damage to our eyes .

Some numbers :

  • 📱In 2022, 95% of French people use a mobile phone or smartphone daily and 83% a computer.

  • 🌐 Almost all young people surf the Internet from a mobile phone: 85% of 12-17 year olds, 97% of 18-24 year olds and 92% of 25-39 year olds¹.

  • 📅 In 2019, Internet users connected on average 22 days in a month , i.e. 4 days more than 10 years ago².

  • ⏱️ On average, the French spend 2h12 each day on the Internet ² (to this are then added all the other digital devices).

¹. Data from the digital barometer of the Ministry of the Economy - Link .
². Data taken from the results of a Médiamétrie survey.


Logically, this new time of digital use acts on our ocular system and causes various pathological manifestations.

Eye fatigue

There digital eye strain tends to become an increasingly recurrent pathology in people who spend very long hours in front of the screen – waiting for a response from their crush on Instagram, for example .

blue eye exposed to blue light

Eye fatigue can cause a variety of symptoms, ranging from mild to severe . This pathology can also affect learning and our productivity.

The symptoms of this fatigue (also called computer vision syndrome) are as follows:

  • 🫣 blurred vision
  • 😵‍💫 Dry and irritated eyes
  • 🤯 Of the headache
  • 😵 Difficulty concentrating
  • 🦒 Neck pain

Good to know : Digital eye strain doesn't just affect adults who spend their days in front of a computer analyzing long graphs like the loading time on Team Fortress 2. No, children are also at risk individuals .

Indeed, major users of digital tools, children are not spared. You should know that before the age of 10, children 's eyes are not yet formed , they are still cute little pokemon in full evolution.

Until adolescence, their pupils are still very fragile, which is why parents must be very careful about the time they spend in front of screens.

If you are interested in this subject, we have given a long article on this subject, to read again on this link: Protect children from blue light .

Age-related macular degeneration (AMD)

Although still debated, scientific studies are increasingly highlighting the risks associated with overexposure to blue light. It could thus cause retinal photochemical damage, causing eye damage and destroying the cells in the center of the retina.

These enemy attacks could play an important role in age-related macular degeneration, leading to accelerated loss of vision .

Disruption of your biological cycle

The white LEDs used in our screens emit a lot of concentrated blue light (Like natural sunlight , even if it doesn't look like it).

This powerful artificial light stimulates our internal biological clock, adding to that already present from the sun , and totally disrupts our circadian cycle (day/night rhythm). That's why you sometimes end up with wide, wide eyes staring at your bedroom ceiling all night long.

Altering your biorhythm will also affect your rest time , which will affect your morale, concentration, mental and physical health, muscles, and your innate ability to win all your fights on Dead or Alive.

To learn more about sleep problems related to blue light, we advise you to read our article: Am I getting enough sleep?

Reading lights and blue light: should we protect ourselves?

E-readers are not exempt from blue light. Their screens can – in the vast majority of cases – give off this harmful brightness although their lighting remains less dangerous than devices with LED screens .

young man reading on his kindle screen sitting on the ground

Some readers have a backlit screen, more concentrated in blue light than natural light, even if most of them today use electronic ink screens.

Electronic ink screen: what is this thing again?

Electronic ink readers are very quickly recognizable since they seem to emit no light. When you read a book on this type of device, you have the impression of reading on a real sheet of paper .

Today, the majority of e-readers ( Kindle Paperwhite, Kobo forma, Vivlio ) use this E-Ink technology, although they still offer integrated lighting (which can be activated/deactivated according to your needs).

On the latest readers, this lighting does not come from under the screen, but from the sides, allowing a less aggressive blue light. But ! There is still blue light.

Do e-readers have blue light filters? 

It depends. From one brand to another, readers may or may not have a filter option.

  • At Kindle for example, the Classic 2019 model and the Kindle Paperwhite 2018 model do not offer this feature, while the Oasis 2019 model does.
  • The same at Kobo : the Clara, Libra and Forma models have a blue light filter to read your code book in the dark, while its Nia model does not.
  • At Vivlio , on the other hand, the last four models in the range (Touch, Color and InkPad3) are equipped with a so-called blue light filter. smart light – which adjusts according to the surrounding brightness.

So what are the dangers?

Reading lights do not entirely eliminate the emission of blue light which may come from their internal lighting . Even if the manufacturers seem to make prodigious efforts to overcome this problem, the emission of this light still exists.

In favor of prevention before cure, we prefer to recommend some solutions to be sure that your retinas will not get tired.

What are the solutions to avoid these dangers?

The enemy is there, before your eyes, everywhere, hidden behind every screen of your daily life. Like a wise man with good advice, we listed you below are some defense techniques to protect yourself from the opponent almost invisible, aka the blue light from your e-reader.

man with blue light blocking glasses reading his kindle e-reader tablet

Wear blue light blocking glasses

There are, in our view, very few solutions either. effective than wearing blue light blocking glasses to protect yourself from the effects of this light wave.

The advantage of glasses is that they can accompany you everywhere with their blue light filter : at work, at home, at your crush, in front of the television, when you use your phone, when you read your latest science fiction novel late at night on your beloved e-reader.

If you're still hesitating to join the Horus-X goggle team, take a look at the blue light filtering goggles from our shop .

Avoid reading at night on your e-reader

Even if the end of the day seems the best time for reading, perhaps prefer a good old dusty grimoire-style book rather than your e-reader.

We understand that this can be a radical solution, but if your device does not reduce blue light, you should avoid using it before going to bed – it might keep you awake longer than expected.

Reduce brightness

As we explained above, some e-readers have anti-blue light features or offer to reduce their backlights to provide a warmer and less aggressive light for our pupils.

Reducing the brightness of your eReader can help reduce the impact of blue light that is emitted from the device . Nevertheless, it must remain comfortable for reading, otherwise you will end up with a big headache from applying yourself to reading the long descriptive paragraphs of the Discworld Annals by Terry Pratchett.

Apply a filter on your eReader

In addition to adjusting the brightness, anti-blue light filters are an interesting solution to block harmful waves from the lighting of your e-reader.

If you wonder how these physical filters work or if they are really useful, we invite you to read our article on this question: Anti-Blue Light Screen Filters . As far as your reader is concerned, we don't necessarily advise you because this solution is permanent and risky if you do it wrong (air bubbles that will deteriorate your reading comfort).

BONUS: Which reader without blue light to choose?

Any reading light with lighting will necessarily emit a little light, but it is possible to dim this lighting to a minimum and drastically reduce the blue light emitted. All of these e-readers are a great choice:

  • Kindle Paperwhite
  • Kindle Oasis
  • Vivlio Touch Lux 5
  • Sony DPT-RP1/B
  • Kobo Clara HD
  • BOOX Nova Air

Kindle Blue Light: All That Can Be Read in Your Eyes…

The latest eReaders are equipped with features to reduce the intensity of their backlighting, there is always a small risk of exposure to blue light even if it is much less than on PC, Smartphone or other LED screens.

When it comes to protecting your pupils, your retina, your cornea, you shouldn't do half measures. If you want to read in peace, remember to put in place some useful little practices to give your eyes the rest they deserve.

Protective glasses, filters, brightness settings… These are all ways to protect yourself against the blue light of your eReader.

Tagged: Lumière bleue