A starter includes an electromagnetic solenoid that generates force for pushing a pinion gear 6 to a ring gear side, and an electromagnetic switch that opens and closes a motor contact point. The system is engaged with a tree so that the needle is disposed into the sapwood of the tree. The set of treatment units is also configured to move along the first direction behind the camera while maintaining the first distance. A portion of the heat spreader device may be optionally exposed. The resulting twice-shifted frequency lies in contraposition to the once-shifted frequency, relative to F2.