Issues with my Lenovo laptop. Black screen?

Issues with my Lenovo laptop. Black screen?

Added (1). So, only happens VERY rarely, usually once a day when I'm using it. It IS plugged in, but when it goes black, it is almost like as if it was updating the display as if I had changed it under the appropriate settings area. Nothing stops running, and it is kind of freaking me out. I use this same laptop for my IT classes, so I can't afford to have something ruin it. If I can stop whatever it is from ruining my computer any further, I WILL NEED to do so.

Did you press f9 t turns of the screen