To prevent the fluctuation of pictures and malfunctions caused by the reflection of radio waves on the internal wall surface of an office and radio waves intruded into the office from the outside by sequentially providing dielectrics having a specific thickness and resistor coating films on both sides of a radio wave reflecting surface on which metallic wire elements are arranged.
A wave absorber 10 having frequency selectivity is composed of resistor coating films 11, dielectrics 12, and a radio wave reflecting surface 14 on which metallic wire elements 13 are arranged, with the dielectrics 12 and coating films 11 being successively provided on both sides of the surface 14. The coating films 11 are required to have such impedance that suppress the reflection of the surface 14 to about ≤10% for sufficiently absorb radio waves to be absorbed. The dielectrics 12 can be made of any material without being limited essentially to vacuum, air, other gases, glass, ceramics, organic high polymers, etc., but must have a thickness of about 1/4 of the wavelength λof radio waves having a frequency to be shielded.
KIYOKAWA KAZUTOSHI
ITO MASAHIKO
NANBA KEIJIROU
NIWAYAMA AKIRA
HASHIMOTO OSAMU
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