In "power management", backlight is translated "rétro-écl." which is in fact short for "rétro-éclairage".
For my part, I prefer the single word "éclairage". Do you *really* think people will confuse backlight with the ambient light in their room ?
So if you choose the short translation (I agree that there's not many space on the screen), I think you'd better use "éclairage" rather than "rétro-écl." that non-techies may not understand. Keep it simple & stupid
