Why do some helicopters have painted (color – schemed esp. three concentric white circles) rotor blades?
It makes them more visible to aircraft above them. Helicopters often fly at low altitudes when working (fighting fires, heli logging, etc) and then exit the work area by climbing. This can create a potential hazard for low flying fixed wing aircraft that are looking for traffic at around their altitude, not helicopters climbing rapidly from below. The painted lines create a flashing effect that can be noticed even if the observer isn’t looking directly at it.
