I was asked this question the other day and didn’t quite know the answer. So in this article, we’re going to talk about what “blue light is” why you should care, and whether e-readers like the Kindle, Kobo, Nook, and other emit Blue Light.
First, let’s just answer the briefest version of the question, and then we’ll get a bit more in-depth.
Do e-readers like the Kindle emit blue light? Yes, most e-readers, even the ones that use e-ink displays like the Amazon Kindle paperwhite do use blue-light spectrums for the backlighting. However, newer versions of these devices use better filtering for the blue light. Many e-readers that have tablet-like functionality, such as the Amazon Fire tablets emit blue light at all times.
Now let’s break this down, talk about which devices actually emit blue light, and how you can protect yourself from it.
What is Blue Light and Why Should I Care?
Let’s just take a second and talk about what Blue Light is, because not that many people actually understand it.
All light is made up of electromagnetic particles that travel in waves of different lengths. These lengths have an inverse relationship to the energy they produce. So, shorter wavelengths have higher energy, and longer wavelengths have lower energy.
The wavelengths are divided into colors and grouped into categories called:
- Gamma Rays
- Ultraviolet Rays (UV)
- Visible Light
- Infrared Light
- Radio Waves
Now, for the purposes of this article, it’s important to understand that your eye is only sensitive to the visible light portions of the spectrums, colors such as blue, green, yellow, orange and red. Blue light, and shades of blue have extremely high amounts of energy and have been shown to not only affect your sleep but to have long term health affects.
Is Blue Light Always Bad?
This is a common misconception, that blue light is always artificial and always bad. In fact, the sun produces blue light and when we’re outside on a sunny day we’re exposed to it constantly. In fact, this is why the sky looks blue because the blue light particles collide with air molecules scattering the blue light.
When we’re outside, that blue light can help boost our alertness, improve our moods and well-being, even give us energy. It also helps our bodies know that it is light outside, and we should be awake. In this way, it helps to regulate our sleep cycles in a positive way.
However, the issue with blue light comes from artificial sources, especially at night.
Why Is Blue Light Bad?
All kinds of devices emit blue light, such as computer screens, cell-phones, smartwatches, tablets and yes, even e-readers like the Kindle. Sometimes this blue-light comes from the screen itself, and sometimes it comes from the backlight for the screen.
Artificial blue light such as this causes our eyes to strain, can give us headaches, even causes macular degeneration and can damage our eyes over time. Blue light exposure has also been linked to certain kinds of cancer, heart disease, diabetes, depression and more.
Besides eye strain, the other most common issue with blue light is how it affects our sleep. Exposure to blue light in the hours before bed inhibits our bodies ability to produce melatonin and affects our circadian rhythm, reducing the quality and quantity of our sleep.
Our eyes do not do a good job of filtering out blue light, which is why so many device manufacturers have started building in blue light filters, and why products such as blue light blocking glasses have become so popular.
Now that we understand a bit better what blue light is, what the benefits are, and what the negatives are, let’s get back to the topic at hand.
Do E-Readers Emit Blue Light?
Like we talked about above, the short answer is obviously yes, most e-readers do emit blue light.
However, how much blue light they emit and from what sources completely depends on the brand and product.
So, I’m going to break this down into individual sections and answer each product individually.
Does The Kindle Paperwhite Emit Blue Light?
Check out the product I’m referring to here.
I’ve talked in other articles about the fact that Kindle tablets do emit a small amount of EMF radiation, but the question today is whether they emit blue light. So, first, let’s talk about the popular paperwhite Kindle tablet from Amazon.
The Kindle paperwhite uses a 300 PPI E-Ink Carta display with a built-in light. That built-in light illuminates the text from the frame so that you can read it clearly day or night.
Although the Kindle paperwhite is one of the least obtrusive blue light-emitting e-readers on the market, it does still emit some blue light.
In fact, a study examining blue light emissions from the Kindle paperwhite along with other devices determined that it still emits enough blue light to disrupt the circadian rhythm.
Does The Kindle Paperwhite Have A Blue Light Filter?
At the time I’m writing this article, there is not a way to disable the blue light other than turning down the lighting in general for the device. Amazon’s other tablet, the Kindle Fire, does have a setting called “Blue Shade” that uses a warmer light to significantly reduce the amount of blue light you’re exposed to, but the Kindle paperwhite does not have this feature.
Some users prefer at night to use their own nightlight to illuminate the screen, instead of the paperwhite’s internal LED lighting.
Or, if you want to permanently filter the blue light from your Kindle Paperwhite, you can use a stick on one like this from Amazon.
Does The Kindle Fire Emit Blue Light?
See the Kindle Fire here.
Unlike the Kindle Paperweight, which is just an e-reader, the Kindle Fire is a full functioning tablet. You can browse the internet, watch Netflix, and read your favorite book.
The Kindle fire, just like any tablet, does emit blue light while you’re using it. It emits about the same amount of blue light that any other tablet will.
Can You Disable Blue Light on Kindle Fire?
Yes! Sometime around 2015, Amazon added a feature to it’s Kindle Fire tablets called “Blue Shade.” It works similar to Apple devices “Night Shift” mode by adjusting the warmth of the light.
To enable blue shade on your kindle fire, just drag your finger down from the top to open the shortcut settings. Then, simply tap on “blue shade.”
You’ll notice that your device will look dramatically orange all of a sudden. That is because by default “blue shade” starts at its maximum settings. You should see a popup at the bottom of your screen, where you can tap to get to blue shade’s advanced settings. There you can reduce how orange the screen is, although doing so will slightly increase the blue light you’re exposed to.
Do Kobo E-Reader Tablets Emit Blue Light?
See products here.
The Kobo line of tablets by Rakuten includes the Kobo Libra, Forma, Clara, and Aura. All of these tablets use similar e-ink displays to the Kindle Paperwhite, in fact, the tablets function very similarly.
The kobo e-books are all backlight e-ink displays, so they will emit a small amount of blue light. However, they have a really cool built-in feature called “Natural Light.” I’ll let their help page describe how it works:
The Natural Light feature gradually changes the color of the screen over the course of the day to make reading more comfortable.
During the day, the screen displays a small amount of blue light. As the day progresses, the light gradually changes to an orange candlelight and contains less blue. Blue light helps keep you alert during the day, but can also keep you awake at night.
The Natural Light feature limits the amount of blue light exposure at night and can help you fall asleep more easily.
Limiting blue light from the eReader’s screen also makes it more comfortable for your eyes when you read in low light or in the dark
So, although the Kobo E-readers do emit blue light, a built-in feature gradually reduces how much blue light you’re exposed to as it gets later in the day.
Does the Nook Glowlight Ereader Emit Blue Light?
See the Nook here.
Just like the Kindle Paperwhite and the Kobo Clara, Barnes & Noble’s signature e-reader, the Nook, does emit some blue light.
It has a similar display to the other tablets, and the LED backlight does give off some blue light. However, just like Rakuten’s Kobo e-readers, the Nook has a built-in feature to combat this.
The Nook Glowlight 3 has “advanced front light technology” that changes the tone of the screen depending on the time of day, filtering out a large portion of the built-in blue light.
In a press release about the feature, Barnes & Noble wrote:
“The automatic setting mimics the sun’s natural progression throughout the day, gradually changing the color on the screen from a cool white during the day to a warmer orange tone – perfect for bedtime reading. Readers will notice and appreciate the reduced amounts of blue light emitted by the LED used in the front light when reading at night.”
Those are the most popular e-readers on the market, so now that we’ve covered those, let’s answer a few related questions.
Which Kindle Tablet Is Easiest On The Eyes?
The Kindle Paperwhite is by far the easiest tablet on your eyes, especially during the day. At night, when you’re using the backlight LED, more blue light is emitted.
The Kindle Fire operates more like a typical tablet and will emit blue light at all times. However, the Kindle Fire does have a blue light filtering mode called Blue Shade that will reduce the blue light quite a bit.
If you do want to reduce the blue light emitted by the Kindle Paperwhite, you can use a stick-on filter like this one from Amazon.
How Can You Block Blue Light From E-Readers?
There are a few strategies you can use to reduce the blue light emissions from e-readers like the Kindle, Kobo, Nook, and others.
1. Use Built-In Technology If Possible
The first thing you should check is whether there is blue light filtering technology built into the device. For example, the Kindle Fire has “Blue Shade” which will adjust the tone to be warmer and emit less blue light. The iPhone and iPad have “Night Shift” which will also reduce the blue light.
Some other e-readers like the Kobo and Nook have light adjusting technology built-in that will slowly adjust the warmth of the light as the day goes on. This means that by the time you’re reading at night, it will be emitting far less blue light.
2. Use A Stick On Filter
This is a great solution to reduce the blue light from any e-reader tablet. They make them for just about any e-reader on the market and are so simple to use. The good ones will filter nearly all the blue light while still maintaining the ability to use the touch screen.
Here is an example of a stick-on filter for the Kindle Paperwhite, but you can find one for your tablet by just searching on Amazon.
3. Use Blue Light Blocking Glasses
Blue light blocking glasses have been gaining popularity for a while, especially if you stare at screens all day. There are tons of great articles out there outlining the best blue light blocking glasses, but my personal favorite is this pair from Amazon.