Object processing state sensing using rf radiation

Abstract

Apparatus and method for applying RF energy to determine a processing state of an object placed in a cavity, during processing of the object. The method includes applying RF energy to the object during the processing via at least one radiating element, receiving RF feedback from in or around the cavity, said RF feedback being indicative of a dielectric response of the cavity and/or the object to electromagnetic (EM) fields excited in the cavity, mathematically manipulating the RF feedback to obtain computed RF feedback, determining one or more processing states of the object based on a correlation between the computed RF feedback and the one or more processing states of the object, and monitoring the computed RF feedback during the applying to monitor the one or more processing states of the object.

What is claimed is: 
     
         1 . A method for controlling energy application to an object, to process the object, in an energy application zone, the method comprising:
 applying energy to the energy application zone according to a first protocol during a first time period before an RF feedback received from the energy application zone meets a criterion; and   applying energy according to a second protocol during a second time period after an RF feedback received from the energy application zone in the presence of the object meets the criterion.   
     
     
         2 . The method of  claim 1 , further comprising: reading, from a machine readable element associated with the object, data indicative of instructions for processing the object and controlling the energy application according to the instructions. 
     
     
         3 . The method of  claim 2 , further comprising: determining the initial processing state of the object based on data read from the machine readable element, and selecting the first protocol according to an initial processing state of the object. 
     
     
         4 . The method of  claim 2 , wherein the instructions include at least one of the first protocol and the second protocol. 
     
     
         5 . The method of  claim 2 , further comprising: reading the criterion from the machine readable element. 
     
     
         6 . The method of  claim 2 , wherein at least one of the first and second protocols includes selecting at least one excitation setup from a plurality of excitation setups, and applying RF energy at the selected excitation setups. 
     
     
         7 . The method of  claim 1  wherein the RF feedback comprises a value indicative of EM energy absorbable by the object. 
     
     
         8 . The method of  claim 1 , wherein applying energy includes applying RF energy. 
     
     
         9 . The method of  claim 1 , wherein applying energy includes at least one of: applying IR energy or applying convection heating. 
     
     
         10 . The method of  claim 1 , wherein at least one of: the first protocol or the second protocol includes a threshold value for the RF feedback. 
     
     
         11 . The method of  claim 1 , further comprising: selecting the first protocol according to an initial processing state of the object. 
     
     
         12 . The method of  claim 11 , further comprising: determining the initial processing state of the object based on RF feedback received from the energy application zone. 
     
     
         13 . The method of  claim 1 , wherein the second protocol includes terminating the EM energy application. 
     
     
         14 . The method of  claim 1 , further comprising: identifying the object. 
     
     
         15 . The method of  claim 14 , further comprising: selecting the first protocol according to the identity of the object. 
     
     
         16 . The method of  claim 1 , wherein the RF feedback is correlated to a processing state of the object that changes during EM energy application. 
     
     
         17 . A method according to  claim 16 , wherein the processing state of the object that changes during EM energy application is indicated by a group consisting of: temperature, moisture, humidity, pressure, chemical composition, volume, weight, color, doneness level, density, taste and crispiness. 
     
     
         18 . The method of  claim 1 , wherein at least one of the first and second protocols includes parameters for applying RF energy at a plurality of excitation setups. 
     
     
         19 . The method of  claim 1 , wherein at least one of the first and second protocols is a default script and wherein the data indicative of instructions comprises an instruction to use the default script. 
     
     
         20 . The method of  claim 1 , further comprising: associating the data read from the machine readable element with information stored in a memory. 
     
     
         21 . The method of  claim 20 , wherein the memory is accessible via a communication network.