My dragons live in our lounge, and we tend to go to bed after they do. Some of them aren't bothered in the least, but some tend to stay awake until you turn all the lights off.
If in doubt, you could pop a cover over.
depends on your beardie, if he stays sound asleep with his light off and yours on, I wouldn't worry. but you could put a blanket over the tank when his lights go off if you're worried about it