The Translation Times blog features a useful review on a tool that can help translators protect their vision:

“This nifty tool should help you protect your vision. It’s a simple and free online tool that will black out the screen at pre-defined intervals. You can either set up a custom break rule, meaning that you tell the system how long of a break you’d like to take every X minutes, or you can use some of their pre-defined rules. Try the 20-20-20 or 60-5 rule. The 20-20-20 rule means a 20-second break after 20 minutes of work,. During the break, you should focus eyes on something that’s 20 feet away. The 60-5 rule means a five-minute break after 60 minutes of work.

Evo, a cute little robot, will be your personal vision-protecting assistant. The program is completely free to use. Get started here. There’s also a handy section for eye gymnastics.”

See: Translation Times