Microwave and far infrared drying under reduced pressure

An apparatus for drying the objects, comprising:

• a pressure reduction tank into which the objects to be dried are placed;
• a microwave heating device equipped with a control board arranged outside the pressure reduction tank to control intermittent or continuous microwave heating at either a prescribed or variable power level;
• the microwave heating device arranged outside the pressure reduction tank, with a forking waveguide to introduce microwave energy into the pressure reduction tank;
• a far infrared heating device equipped with a control board arranged outside the pressure reduction tank to regulate the temperature generated by such far infrared heating;
• the far infrared heating device equipped with far infrared heaters arranged inside the pressure reduction tank;
• a metallic element having a single or plural number of sharp edge arranged inside the pressure reduction tank;
• the metallic element located where an electrical discharge can be detected except where a metallic element disturbs the objects to be dried;
• the metallic element making an electrical discharge occur due to microwave energy;
• a device for detecting an electrical discharge that occurs at the metallic element due to microwave energy;
• and
• the device for detecting electrical discharge that is linked with a microwave power unit to stop or pause the microwave heating.