Screen started acting up, now is all black. Why?

Last night battery was fully charged, put it in airplane mode and fell asleep.This morning worked fine, then all of a sudden the screen was black with horizontal green lines across. Then it went back to normal but some of the lighting would flicker. Was most noticeable wherever it was displaying something gray or white. Then it went back to straight black but when you tapped the screen the blue corner lights would still illuminate. Now it doesn't even do that.

But I am still getting notification alerts via the different colors of the dot in upper left corner.

Phone has not been abused.