Method and apparatus for adjusting characteristics of multi electron source

A characteristics adjustment apparatus for adjusting electron emission characteristics of each of a plurality of electron emitting devices disposed on a substrate of a multi electron source, comprising:

• a selection control circuit for selecting the electron emitting devices constituting the multi electron source;
• a pulse peak and width value setting circuit for setting pulse peak and width values of a voltage to be applied to each of the electron emitting devices;
• a drive circuit for applying the voltage set by said pulse peak and width value setting circuit to the electron emitting devices selected by said selection control circuit;
• a circuit for measuring an electron emitting current of the electron emitting device driven by said drive circuit;
• a memory for storing a measured value of the electron emitting current;
• a calculation circuit for creating a characteristics adjustment table in such a manner that said selection control circuit selects some of the electron emitting devices, said pulse peak and width value setting circuit sets a plurality of characteristics shift voltages having discrete values, said drive circuit drives some of the electron emitting devices, an average of change rates of the electron emission characteristics of some of the electron emitting devices is calculated in accordance with values measured by said measuring circuit when each characteristics shift voltage is applied, and in accordance with the calculated average, the characteristics adjustment table is created for adjusting electron emitting current characteristics of the electron emitting devices;
• a memory for storing the characteristics adjustment table and the pulse peak and width values of the characteristics shift voltage to be applied to the electron emitting devices;
• and
• a control circuit for setting again the values set by said pulse peak and width value setting circuit in accordance with the characteristics adjustment table and the electron emitting current.