I would not worry about burn-in. Modern LCDs are much more resistant to this, it's not like the old rear-projection or plasma TVs. The worst that can happen is backlight or inverters wearing out, and even that is very rare as long as the manufacturer doesn't cheap out on those parts.
Simply turn the backlight down to minimum or close the lid if your laptop does not enter sleep mode (test this!).
Otherwise I suspect adding power management features opens the pandora's box of compatibility issues.
Good luck!
Simply turn the backlight down to minimum or close the lid if your laptop does not enter sleep mode (test this!).
Otherwise I suspect adding power management features opens the pandora's box of compatibility issues.
Good luck!