Microwave treatment device

A microwave treatment device comprising:

• a heating chamber configured to accommodate a heating target;
• a microwave generator operable to generate a microwave having an arbitrary frequency in a predetermined frequency band;
• an amplifier operable to amplify the microwave and output, as incident microwave power, the microwave amplified;
• a feeder configured to supply the incident microwave power to the heating chamber;
• a detector operable to detect the incident microwave power and reflected microwave power that returns from the heating chamber to the feeder;
• a controller operable to control the microwave generator and the amplifier;
• and
• a storage operable to store the incident microwave power and the reflected microwave power together with the frequency of the microwave and time elapsed since a start of heating, wherein
• the controller is operable to cause the microwave generator to execute a frequency sweep over the predetermined frequency band and is operable to control the microwave generator and the amplifier based on the incident microwave power and the reflected microwave power detected during the frequency sweep, wherein
• the controller is operable to, in changing the frequency of the microwave, set a non-operating time during which the microwave is not output, and change the non-operating time according to the frequency of the microwave, the non-operating time for each frequency being fixed in dependence with the reflected microwave power at each frequency.