To improve absorbing efficiency of a radio wave without increasing the thickness in a radio wave absorber having stack structure provided with a matching layer for easily absorbing the radio wave from the outer air, an absorbing layer for absorbing the radio wave passing through the matching layer, and a reflection layer for reflecting the radio wave passing through the absorbing layer to an absorbing layer-side.
In a radio wave absorber, an absorbing layer 13 is formed of at least two layers provided with first to fourth absorbing layer parts 16-19. In the matching layer 12 and the absorbing layer parts 16-19, the relative dielectric constant of the layer positioned to a reflection layer 14-side in the two contact layers is set to be higher than that of the matching layer 12 or the layer positioned to a matching layer 12-side but to be not more than three times. An incident radio wave 15 is refracted in the respective interfaces of the matching layer 12 and the absorbing layer parts 16-19. Thus, the route of the radio wave 15 is made to be long and the absorbing efficiency of the radio wave 15 is improved.
KOJIMA ATSUSHI
SAKAMOTO YUKIO
SUGITANI MASAMI
ARAKAWA HAJIME
