Patent ID: 7030628

Claim:
A charge potential evaluation method comprising: (a) acquiring, in an object to be measured that has a first conductor and a second conductor opposed to each other with a dielectric therebetween, a value of a relative permittivity of the dielectric and a distance between the first and second conductors; (b) measuring, in a predetermined atmosphere, a potential V c of a conductive plate facing a grounded surface with a predetermined distance therebetween; and (c) converting a potential difference V h between the first conductor and the second conductor in the object to be measured in the atmosphere, using the following expression (1), V h = d h ɛ h · ɛ c d c ⁢ V c [ Expression ⁢ ⁢ 1 ] where d h denotes the distance between the first conductor and the second conductor in the object to be measured, d c denotes the distance between the conductive plate and the grounded surface, ε h denotes a relative permittivity of the dielectric in the object to be measured, and ε c denotes the relative permittivity between the conductive plate and the grounded surfaces, wherein ions are produced by an ionizer to form an atmosphere in which the conductive plate and the grounded surface are to be disposed.