Patent ID: 7623058

Claim:
An electromagnetic wave absorbing plate composed of a transparent plate-like dielectric, wherein a thickness of the dielectric is determined for an electromagnetic wave absorption quantity Ai determined by the following equation (2) to be equal to or greater than 10 dB using an incident side impedance Zxi determined by the following equation (1) at a time at which the electromagnetic wave becomes incident on a surface of the dielectric and, in the equation (1), ∈ denotes a complex dielectric permittivity of the transparent plate-like dielectric, μ denotes a relative permittivity of the transparent plate-like dielectric, λ i denotes a wavelength of the electromagnetic wave, and d denotes the thickness of the transparent plate-like dielectric in meters, and Zr denotes an input impedance of the dielectric side and, in the equation (2), Γ i denotes a reflection coefficient of the electromagnetic wave of the surface of the dielectric and determined by (Zxi−1)/(Zxi+1), Zxi = μ ɛ ⨯ tanh [ ( 2 ⁢ j ⨯ π λ i ⨯ ɛ ⨯ μ ⨯ d ) + a ⁢ ⁢ tanh ( Zr 377 μ ɛ ) ] ( 1 ) A i = 20 ⨯ log ⁡ (  Γ i  ) . ( 2 )