2D Lightning area in a Top-down game

Hi! I need help with some illumination. The question is: How do I make a light that just show you (the player) in the game screen, and, when you are NEAR to an other scene object, it will be revealed to you. Here have some wireframes to be clearer.

Sorry for any English mistake!

You could draw a full-screen image of a black area, with a circle cut out of it, over the top of everything else afterwards.