what does the light blue display icon mean?

In ARD, in the pane with the clients, you have a blue dot, then an icon that looks like a display, then the text info....

What does the display icon mean, and what do the different colors represent?

From my experience, dark blue means that everything works...Dark grey means the machine has not been added to ARD...I can't figure out what the light blue is supposed to represent, if anyone can let me know, that would be most useful...

Thanks!