Impedance matching device provided with reactance-impedance table

An impedance matching system comprising an impedance matching unit and an output characteristics analyzing unit,

• wherein the matching unit includes:
• an input terminal connected to a high frequency power source;
• an output terminal connected to a load;
• at least one variable reactor arranged between the input terminal and the output terminal for matching impedances of the power source and the load;
• an input detector that detects voltage and current of high frequency power supplied from the power source;
• and a matching controller that matches the impedance of the power source and the impedance of the load by adjusting reactance of the variable reactor based on detection data from the input detector;
• and
• wherein the analyzing unit includes:
• a storage that stores reactance-impedance data representing relations between data on a plurality of preselected reactances of the variable reactor and data on impedance at the output terminal, the reactance-impedance data being produced with the input terminal connected to the power source or an equivalent of the power source before the output terminal is connected to the load;
• and an analyzer that analyzes electric characteristics at the output terminal based on both data about the reactance adjusted by the matching controller and the reactance-impedance data.

A method of analyzing electric characteristics at an output terminal of an impedance matching device provide with an input terminal and a variable reactor arranged between the input terminal and the output terminal, the method comprising:

• producing reactance-impedance data while the input terminal is connected to a high frequency power source or an equivalent of the power source and before the output terminal is connected to a load, the reactance-impedance data representing relations between data on a plurality of preselected reactances of the variable reactor and data on impedance at the output terminal,
• supplying high frequency electric power to the input terminal while the input terminal is connected to the power source and the output terminal is connected to the load,
• detecting high frequency voltage and high frequency current at the input terminal,
• adjusting reactance of the variable reactor based on data on the detected high frequency voltage and current, so at the impedance of the power source and the impedance of the load are matched to each other, and
• analyzing the electric characteristics at the output terminal by using data on the adjusted reactance and the reactance-impedance data.