A system for preparing food that includes a holder for holding the food and an apparatus. The apparatus includes a processing chamber that is RF-impermeable and air-impermeable, a holding device for holding the holder inside the processing chamber, an RF-antenna to radiate RF-energy to the inside of the processing chamber for heating the food inside the holder, a fan for circulating the air in the processing chamber through an air-permeable side and through the holder, and a heater to provide heat to the circulated air. The fan and the heater are to air fry the food inside the holder. The processing chamber includes a top shell having a top inner space and a top rim forming an access opening to the top inner space, and a bottom shell having a bottom inner space and a bottom rim forming an access opening to the bottom inner space. In a closed position, the top shell and the bottom shell are to envelop an interior space that includes the top inner space and the bottom space. The processing chamber is shaped such that the RF-wave has a node substantially at the top rim and/or the bottom rim in the closed position.

A system for preparing food that includes a holder for holding the food and an apparatus. The apparatus includes a processing chamber that is RF-impermeable and air-impermeable, a holding device for holding the holder inside the processing chamber, an RF-antenna to radiate RF-energy to the inside of the processing chamber for heating the food inside the holder, a fan for circulating the air in the processing chamber through an air-permeable side and through the holder, and a heater to provide heat to the circulated air. The fan and the heater are to air fry the food inside the holder. The processing chamber includes a top shell having a top inner space and a top rim forming an access opening to the top inner space, and a bottom shell having a bottom inner space and a bottom rim forming an access opening to the bottom inner space. In a closed position, the top shell and the bottom shell are to envelop an interior space that includes the top inner space and the bottom space. The processing chamber is shaped such that the RF-wave has a node substantially at the top rim and/or the bottom rim in the closed position.

A microwave treatment apparatus includes a treatment chamber, a microwave supply, and a resonator unit. The treatment chamber is surrounded by a plurality of walls, and accommodates a heating target. The microwave supply supplies a microwave to the treatment chamber. The resonator unit is provided on one wall of the plurality of walls, and the resonator unit has a resonance frequency in a frequency band of the microwave. In this embodiment, the impedance of the surface of the resonator unit can be changed by controlling the frequency of the microwave supplied to the treatment chamber. This makes it possible to control the standing wave distribution within the treatment chamber, that is, the microwave energy distribution within the treatment chamber. As a result, in the cases where a plurality of heating targets need to be heated simultaneously, desired dielectric heating is conducted for each of the heating targets.

A microwave treatment apparatus includes a treatment chamber, a microwave supply, and a resonator unit. The treatment chamber is surrounded by a plurality of walls, and accommodates a heating target. The microwave supply supplies a microwave to the treatment chamber. The resonator unit is provided on one wall of the plurality of walls, and the resonator unit has a resonance frequency in a frequency band of the microwave. In this embodiment, the impedance of the surface of the resonator unit can be changed by controlling the frequency of the microwave supplied to the treatment chamber. This makes it possible to control the standing wave distribution within the treatment chamber, that is, the microwave energy distribution within the treatment chamber. As a result, in the cases where a plurality of heating targets need to be heated simultaneously, desired dielectric heating is conducted for each of the heating targets.

Disclosed are 3D printing equipment, a system, and a method for food design and production. The 3D printing equipment has a bipolar microwave heating antenna for focusing heating on a material in an extrusion nozzle. The extrusion nozzle is between the anode antenna and the cathode antenna of the bipolar microwave heating antenna. The anode antenna and the cathode antenna limit a microwave electric field between them, thereby implementing focused heating on the material.

An embodiment of a microwave heating apparatus includes a solid state microwave energy source, a chamber, a dielectric resonator antenna with an exciter dielectric resonator and a feed structure, and one or more additional dielectric resonators each positioned within a distance of the exciter resonator to form a dielectric resonator antenna array. The distance is selected so that each additional resonator is closely capacitively coupled with the exciter resonator. The feed structure receives an excitation signal from the microwave energy source. The exciter resonator is configured to produce a first electric field in response to the excitation signal, and the first electric field may directly impinge on the additional resonator(s). Impingement of the first electric field may cause each of the additional resonators to produce a second electric field. The electric fields are directed into the chamber to increase the thermal energy of a load within the chamber.

An embodiment of a microwave heating apparatus includes a solid state microwave energy source, a chamber, a dielectric resonator antenna with an exciter dielectric resonator and a feed structure, and one or more additional dielectric resonators each positioned within a distance of the exciter resonator to form a dielectric resonator antenna array. The distance is selected so that each additional resonator is closely capacitively coupled with the exciter resonator. The feed structure receives an excitation signal from the microwave energy source. The exciter resonator is configured to produce a first electric field in response to the excitation signal, and the first electric field may directly impinge on the additional resonator(s). Impingement of the first electric field may cause each of the additional resonators to produce a second electric field. The electric fields are directed into the chamber to increase the thermal energy of a load within the chamber.

An embodiment of a microwave heating apparatus includes a solid state microwave energy source, a first dielectric resonator antenna that includes a first exciter dielectric resonator and a first feed structure in proximity to the first exciter dielectric resonator, one or more additional dielectric resonators stacked above the top surface of the first exciter dielectric resonator to form a vertically-stacked dielectric resonator antenna array. The first feed structure is electrically coupled to the microwave energy source to receive a first excitation signal, and the first exciter dielectric resonator is configured to produce a first electric field in response to the excitation signal provided to the first feed structure.

An embodiment of a microwave heating apparatus includes a solid state microwave energy source, a first dielectric resonator antenna that includes a first exciter dielectric resonator and a first feed structure in proximity to the first exciter dielectric resonator, one or more additional dielectric resonators stacked above the top surface of the first exciter dielectric resonator to form a vertically-stacked dielectric resonator antenna array. The first feed structure is electrically coupled to the microwave energy source to receive a first excitation signal, and the first exciter dielectric resonator is configured to produce a first electric field in response to the excitation signal provided to the first feed structure.

A method of forming a microwave applicator comprising forming a body comprising dielectric material so that there is a void in the dielectric material, and depositing conductive material in the void to form a feed for coupling energy into the dielectric material.