Patent ID: 8744316

Claim:
A charged particle generator comprising: a first electrode; a second electrode; and an insulating material that is provided between the first electrode and the second electrode, wherein the first electrode includes a first layer, a second layer, and a third layer, the first layer and the second layer being resistive layers having different values of volume resistivity, the first layer contacting the insulating material, the second layer contacting the third layer, and the third layer being a conductive base material, wherein charged particles are generated by discharge that occurs between the first and the second electrodes, wherein the first electrode, the insulating material, and the second electrode are arranged in a first direction, wherein the second electrode has an opening that is open in the first direction, wherein the insulating material has a region limiter, wherein the region limiter is a space that is open at one end in the first direction and continuous to the opening, that is closed at the other end in the first direction by the first electrode, and that is surrounded by the insulating material in a second direction, and wherein an area of the opening is larger than that of the region limiter.