Well, it seems that you are trying to protect your eyes and improve your vision. So, as a matter of fact, yes it is harmful for us if we try to get much too close to the computer screen which gives out a lot of harmful lights to our eyes. And in order to reduce the harm as much as possible, we should keep the distance at at least 3/4 meter. Also, we need to take breaks from time to time. and pay due attention if we want to be healthy.
It is the 60cm that is the proper distance between your distance and the computer which will make your eyes not that tired. Now many people use the computer during work for much time. We should keep notice of this distance. Or else, our eyes will get tired and become short sighted.
The distance of computer screen and eyes can affect our eyes health. Excessively closing to the computer screen would develop more vulnerable to radiation damage. To protect eyes, the first to have good posture, the distance should maintain 60 centimeters or more distance. Putting screen lower appropriately, because the line of sight down about 30 degrees, the eye muscles in a rather relaxed state, can maximum relax eyes,