Yes, I also agree with what your father has told you. So you'd better not watch too much TV or be sitting in front of the computer for a long time. They do damage you eyes. Let's talk about the reasons. According to the experts, watching the television or the computer is enough exposure of the eyes to a constant light source. In this way, Strong light from them can cause serious damage not only to the cornea, but also to the lenses. At this moment, just like you feel, it can just like there is sand in the eyes and it will also lead to constant pain when eyes encounter some light of particular wave lengths. Besides, when too much light goes into your eyes, especially for a long time, it will increase the eye strain and then can lead to many other eye diseases. So just don't watch tv or computer in a long time. And also, you should control the distance between you and the machine.