Eyes problems (computer related)

I am a computer programmer and I have problems with my eyes (started two years ago and worsening all the time): they start to hurt after a few hours of work in front of the computer and it is very difficult for me to continue working in this state. I also believe that there can be many people with conditions resembling mine, who also work with computers throughout the day. And if anyone can recommend a treatment or exercises, to improve my eyes – I would like very much to read them. My eyes are constantly red and I’ve already done the regular things: giving a rest every hour or so, spending less time in front of the computer screen, using the artificial tears eye drops. My eyeglasses are perfect for me – I’ve been to 2 optometrists. Sadly, my eyes continue to deteriorate. I have visited three doctors – they haven’t said anything. I cannot believe that there’s nothing to be done!