Say a person had no eyelids, how do they sleep?

Question

Is it even possible for someone to go into deep sleep with their eyes fully open and how can they protect their eyes from germs and dust if they cannot blink?

Answer 1

I think when you go to sleep your eyes roll back so its just the white bits showing

Answer 2

They don't.

Answer 3

I know a guy. An insect bit him on the face and he could not close one eye but that's how he slept, with one eye open. Maybe its the same principle as fish. Sorry, don't know about the germs.