We have already talked about how much computer screens and smartphones can ruin sleep because of their blue light. For this reason, many clinical studies advise not to use the smartphone or tablet in bed before going to sleep, if you do not want to have problems falling asleep and during sleep.
Fortunately, this is not true in an absolute sense and it is still possible to use the mobile phone or smartphone in bed before sleeping, without ruining sleep and rest.
The important thing is to limit the blue lights of the LCD screen which is primarily responsible for sleep problems.
The scientific explanation says, in a nutshell, that the light of electronic screens can interfere with the production of melatonin, which controls the natural sleep-wake cycles.
However, the Mayo Clinic has found the minimum brightness to be used in order not to interfere with melatonin .
The secret is to lower the brightness of the smartphone or tablet to at least 30, keeping the device at least 14 cm from the face during use.
The researchers found these values by experimenting with the use of two tablets and a smartphone in a dark room, measuring different degrees of brightness and various distances from a person's face.
The result is that when the brightness settings have been lowered and the screens are far enough away from the eyes, the risk of light suppressing melatonin secretion and disturbing sleep is reduced.
Basically, if you want to read a book or play on the tablet in bed, there is no problem, as long as you lower the brightness, perhaps to the minimum, keeping it far enough from your eyes.
To support this way of using the mobile phone in bed there are some applications.
In other articles we have found and tried automatic apps for Android to change screen brightness and also an app that creates a filter to rest your eyes in the evening, without lowering the brightness.
For PC you can use F-Lux which changes the brightness and coloring of the screen according to the time.
From 2016 you can activate the night mode on iPhone and iPad
