Half-silvered glass behind a LCD screen

Instead of having a back-light at the back of an LCD screen, I'm wondering if you could have half-silvered glass(which will create a mirror in the light). You have a back-light behind the half-silvered glass(which would allow light through when it is on). You have a light sensor that detects light, and when too much light hits it, it shuts off the back-light, so the half-silvered glass will be a back-light for it.

Would this work, or would you(if you're in front of the screen) be imprinted in the background of the screen display?