Not backlit at all, good news is this means it reads as well in direct sunlight as it does in low light conditions. Bad news is you need a bedsight light, book light, etc.
I have used mine in bed several times using a book light clipped to the bill of a baseball cap. Pointed at the Jetbook, if your book light is good its more than enough to read by.
Plus it automatically goes where you point your head.
Jetbook also sells an "ear light" that clips onto your ear for doing the same thing.