Patent ID: 7071626

Claim:
A plasma generator, comprising: a plasma forming space into which air is introduced; a dielectric provided in the plasma forming space; and band plate-like first and second electrodes arranged in opposed relation to each other on respective surfaces of the dielectric in the plasma forming space, wherein plasma is generated by discharge caused by applying voltage between the first and second electrodes, and the first and second electrodes are provided on the respective surfaces of the dielectric so as to be relatively displaced in a surface direction of the dielectric so as to satisfy equation 1, equation 2 and equation 3: tan ⁢ ⁢ θ 2 = L1 d ( Equation ⁢ ⁢ 1 ) tan ⁢ ⁢ θ 1 = 1 ɛ 2 ⁢ tan ⁢ ⁢ θ 2 ( Equation ⁢ ⁢ 2 ) 26 × 10 6 ⁡ [ V ⁢ / ⁢ m ] ≧ cos ⁢ ⁢ θ 1 · sin ⁢ ⁢ 2 ⁢ ⁢ θ 2 d ⁢ ⁢ sin ⁢ ⁢ 2 ⁢ ⁢ θ 1 ⁢ V = E 1 ⁡ ( max ) ( Equation ⁢ ⁢ 3 ) where: L 1 is a separation distance in the surface direction of the dielectric between a front end edge of the first electrode and a corresponding end edge of the second electrode, which is located on an outside in a displacement direction of the electrodes from the front end edge position of the first electrode and which is closest to the front end edge position of the first electrode, θ 2 is an angle formed by an imaginary plane including the front end edge of the first electrode and the end edge of the second electrode across a thickness of the dielectric, d is a thickness [m] of the dielectric, V is an intensity [V] of the voltage applied between the first and second electrodes, θ 1 is an outgoing angle of an electric field in the plasma forming space at a boundary surface of the dielectric, ∈ 2 is a dielectric constant of the dielectric, and E 1 (max) is a maximum value [V/m] of the electric field at the end surface of the electrode.