Blue light filter: all the information ?? 【Best explanation】

In this article we are going to deal with the blue light filter issue and how its use beneficially affects our eyes to prevent the amount of it that we are exposed to, let's get in trouble!

We are surrounded by them from the time we get up until we go to bed, at home and at work. Screens and monitors are an important part of our lives for almost all areas, and with them come issues like vision problems, visual overload, or eyestrain.

Index of contents

Light and wavelength

Before getting into the blue light concepts, let's start with the basics: we call the radiation that we perceive in the visible aspect, which is between 380 and 750 nanometers (one nanometer equals one millionth of a meter). However, the existing total light wave range (visible and invisible) varies in astronomical amounts from kilometers to less than one picometer (one thousandth of a nanometer). To avoid turning this article into a science class, let's skip the "invisible" light section (infrared, thermal, and so on).

Electromagnetic light scheme made by Horst Frank.

In the narrow range that we perceive as Visible Light between 380 and 750 nm, all the colors that we perceive are divided, from blues (380nm) to reds (750nm). The purplish and blue range has a much shorter wavelength and as we move towards warmer colors it lengthens. This translates to Christian by saying that the blue lengths are short and have more energy (UltraViolet), while the red ones are long and weaker (InfraRed). Take a look at the outline:

What is blue light?

Blue stripe wavelength showing the difference between the two

Seeing all this, the fact of the matter comes: around 25% of the light that surrounds us is blue (from 380nm to around 495nm). As in all other colors, we can find various shades depending on their wavelength. For the topic that brings us here today, we will focus on two in particular:

Light blue violet

the violet blue * transmits a deceptive sensation: it may seem like a "darker light", but its wavelengths are the highest in the visible spectrum and are therefore the most aggressive with our vision. Prolonged exposure to this lighting produces short or long term negative effects such as:

• Tiredness Visual stress Damage to the retina Photokeratitis (corneal burns) Macular degeneration (commonly associated with age)

* Note: we should not confuse violet blue with what we commonly call "black light", whose lighting depends both on its insulating screen (Wood glass) and the use of a single phosphor.

Light turquoise blue

On the opposite side of blue wavelength, there is turquoise. Obviously we do not want you to think that blue light is the Antichrist, far from it, and although it may surprise you, we must tell you that this type of blue also has beneficial effects:

• Regulates the biological circadian cycles (it is the light associated with dawn). It stimulates memory and learning capacity. It increases brain activity and performance. It helps protect the eyes from solar radiation. It improves mood.

How the blue brightness of the screens affects us

You can imagine where the problem is: all the screens of our monitors, mobile devices and televisions emit in a violet blue spectrum. Added to the specific adverse effects of blue violet that we cited above there are other issues to consider:

• There are studies showing that LED light stimulates cell degeneration due to its high lumen frequency. This is especially notable in the macula (posterior area of ​​the retina), which is extremely sensitive to light and does not have regenerative properties. All screens and monitors transmit using blue light, the problem for our eyes is that it is more intense and bluer (worth the redundancy) than the light that we naturally perceive in the environment. Our eyes, designed to allow us to see with great sharpness, color gamut and depth perception, are not physiologically prepared to filter this excess blue light. Continued use of screens produces dry eyes. This is due to the effort required by the eye to maintain the same focus for a long time generates alterations in the rhythm in which tear cells usually hydrate our eyes when blinking. Irritation from prolonged exposure to screens causes what we know as red eyes, which do not It is another thing that an inflammation gives the blood vessels due to various causes. In these cases, it is associated with visual fatigue due to light overexposure or ocular hypertension. Other discomforts that can be suffered are blurred vision or burning. Using our screens in low-light environments or as the only light source generates glare. The same is what produces the alterations in the rhythms of sleep, given that due to its intensity our eyes exposed to blue light receive stimuli associated with sunlight. This reduces the production of melatonin in our body, the hormone that makes them drowsy.

With regard to this last point, that of using the devices before going to sleep, this is what we address in the next section: night mode.

Blue filter and night mode

Wavelength of the two types of blue: violet and turquoise

Something that not everyone knows is that the famous "blue light filter" is not called that because it is a blue filter as we might think, but because it counteracts this color range. Although it may surprise, the blue light filter is made to have reddish or yellowish tones.

Depending on the operating system or applications, the night mode itself can be customized to some degree, giving users more freedom to calibrate it. There are also options to program the time they are activated, or devices that include the option of automatic brightness depending on the lighting of the environment.

Why a red filter?

As we discussed at the beginning of this article, blue and red light are on opposite sides of visible light, the first having short high energy waves and the second long low energy waves. In short: it is more relaxing on screen. This makes red an ideal color to create a "protective layer" to counter the default blue lighting. Red changes the temperature of the screen, it is also designed to decrease its brightness and in fact we can see these measures in the technology of e-books, designed to be able to read for long periods of time without resenting our sight.

For phones and tablets, night mode is intended to reduce glare, introduce warm undertones, and, through some applications, create environments where dark colors dominate more than whites to reduce contrast.

Solutions to blue light

Today we have a much deeper knowledge of the negative effects that this world of screens exerts on our eyes and vision, which is why we find more and more palliatives to increase our comfort when using them (since stopping makes it seem impossible). Here we leave you some applications the sea of ​​patches with which to reduce the problems of blue light.

Windows, MacOs and Linux

Night Light (Windows 10)

Exclusive to Windows, Night Light arrived in the Windows 10 update in April 2017. It can be programmed in two ways: either the screen can change its tone at a specific time (21:00 for example) or it can do so progressively throughout the day. Activating it is simple:

1. Press the Window key s + "i". The Configuration window will open. Click on System and then enter Screen (the first item in the list, which should open automatically when entering System). We activate night mode.

   

   Route to activate Night Mode

F.lux (F.lux Software LLC)

F.lux is an open multi-system program (Microsoft Windows, macOS, GNU / Linux, Android, iOS) and was one of the first to appear and bring blue light solutions from devices. In a section of its website you can find a dynamic table with which to interact and observe how it makes changes to the light emission of the system. It is free for private use and has a business license.

Night Shift (Mac OS)

The Night's Watch is an exclusive Apple software for all its devices and is available for those of its products that have the MacOS Sierra version 10.12.4. These are, models released from mid-2012 onwards. For them, the way to activate it is as follows:

1. Select Apple Menu > System Preferences, then click Screens. Click the Night Shift tab.

   

   Path to activate Night Shift

Iris mini (Iris Tech)

Iris is blue light protection software compatible with all operating systems (Yes, Linux users, we know you are there and we love you). We can also find it for smartphone and tablet as it is totally multi-platform and you can even download it only for your Chrome browser. More facilities impossible.

Smartphones and tablets

Twilight (app.)

Twilight is a blue light filter app available on the Play Store only for Android. Programmable and with filters of different intensity, it is a very complete application to install on our mobile or tablet.

Ascendik (app.)

Like Twilight, it has a catalog of filter modalities to customize and its settings can be saved. Available in the Play Store only for Android.

F.lux and Iris mini

We mentioned them in the section of laptops and desktops, but we remind you that you can also install their tablet and smartphone versions.

Debate on blue light and rest

Just as the view that blue light from devices is adverse to us is quite widespread, there are also voices that differ. According to some experts, it is not the blue light of devices that neutralizes our ability to be drowsy, but the activities we carry out with them are stimulating.

Many argue that, in fact, blue tones are associated with night and rest. The moonlight itself is bluish. Blue is considered a relaxing and cold color, especially those that move in the paler ranges. Also in defense of blue light we can find as an argument that phototherapy treatments to treat problems such as stress and insomnia use blue light among other colors.

We know that the use of applications and social networks are activities that generate endorphins in our body, which is why they are stimulating to us. This delays the melatonin production necessary for drowsiness. However, we can assume that in many cases the circadian cycle mismatches are also due to using screens with excessive brightness in low light or loud sounds. A responsible use of them in the hours prior to rest may be the best measure to take.

Conclusions on the blue light filter

Taking into account our pace of life and its relationship with new technologies, it does not look like it will slow down in the short term. It is beneficial that we are aware of the drawbacks that the use of screens both due to excess brightness and in low light conditions have for our vision.

We believe it is important to take care of our eyes, especially since we only have one pair. The number of people with vision problems or the need to wear glasses continues to increase. We must maintain healthy lifestyle habits, such as not using screens an hour before bed, respecting the minimum recommended distance and not using them with excessive brightness are great tips.

It is for this reason that for those who live glued to a monitor, activating the blue light filter or using the night mode if available will increase our comfort in the short and long term. We leave you here some related topics that we have discussed on our website:

• Our guide on the best monitors on the market Computer glasses and blue light Reduced blue light in new versions of iOS

With nothing more to add, we hope that today's article has been useful to you, comment as always with any questions that may arise. Until next time!