It was the little muscles in the back of my eyeballs that help focus.
Once I woke up with double-vision in my eye that didn't go away for two days and I thought I was going blind.
Just keep eating your vegetables and you should have decent sight until the singularity when we'll all have super cyber eyes.
I probably shouldn't have said that because I'll probably get super-cancer when I'm 50 and not be able to afford the "cheap" cancer pills to keep me alive.
Assuming they have such a thing as cancer-curing pills by then. Assuming we're even here.
You'll get used to it, trust me.
In a few days you'll use a computer terminal at default color temperature and wonder how the fuck you ever used them that way.
Just change the color temperature to somewhere between 2000 and 3000K or install f.lux, I wouldn't bother with buying glasses.
Helps with the eye strain a little.