[CentOS] Way to tell if monitor is on or off???

I am looking for a way to tell if the monitor is on or off?
xset q  - seems to only work if DPMS turns off the monitor.

If I or someone actually turns off the monitor xset q still shows on.
If I do xset dpms force off ; sleep 5; xset q the monitor shows off.

So is there a way to tell if the monitor is actually on or off?

Thanks,

Jerry