Proof-reading On Screen - The Bane of a Writer's Eyes?

When I was a kid, there was a saying that if you watched too much television you would end up with square eyes. Fortunately, it was something I didn’t have to worry about as I didn’t watch much television – and I still don’t – but the saying came to mind a few days ago after spending much of the last three weeks in front of a computer preparing my next novel for publication. Not that I really think I’m developing square eyes but, at the end of a day of intense focus on a computer screen, they often feel that way.