Dielectric heating device and liquid ejection system

A dielectric heating device comprising:

• a first electrode unit that has a first electrode and a second electrode facing a medium and that heats the medium by a dielectric heating method;
• a voltage applying section that applies an AC voltage to the first electrode and the second electrode;
• a carriage on which is mounted the first electrode unit;
• a moving section that causes the first electrode unit to reciprocally move at least above the medium along a scanning direction by reciprocating the carriage along the scanning direction;
• and
• a heating control section that controls the voltage applying section and the moving section, wherein
• the heating control section executes heating control of heating the medium while moving the first electrode unit along the scanning direction in at least one of an outgoing path in which the first electrode unit moves in one direction of the scanning direction and a return path in which the first electrode unit moves in a direction opposite to the one direction and
• in the heating control, the heating control section
• sets an electric field strength formed by the first electrode unit when the first electrode unit is positioned at a first point overlapping one end section of the medium in the scanning direction to a first electric field strength,
• sets an electric field strength formed by the first electrode unit when the first electrode unit is positioned at a second point overlapping a center section of the medium in the scanning direction to a second electric field strength that is stronger than the first electric field strength, and
• causes movement speed of the first electrode unit at the first point to be slower than movement speed of the first electrode unit at the second point.