Dell Lattitude E7440 screen not appearing

Hello,
I was using my laptop from the last 4 hours and then i just close the lid of my laptop wothout putting it to sleep mode. And when i tried to power on my laptop after 10 minutes nothing appears on the screen while the power light is on... i tried to force shut down the laptop and also removes it battery and put that again but that also didn't work... can u please help me in this issue...?
Thanks