Electromagnetic wave absorbing sheet for millimeter wave band and millimeter wave radio wave absorption method

摘要

A radio wave absorber having excellent electromagnetic wave absorption performance in the millimeter wave band frequency and excellent in light weight and flexibility is provided.Radio reflection layer (a) andA radio wave absorbing lower layer (b) arranged parallel to the top of said radio wave reflection layerA radio wave absorbing upper layer (c) disposed parallel to the upper portion of said radio wave absorbing lower layer (b) is provided.The radio frequency absorbing lower layer (b) has a real portion of the relative dielectric constant at a frequency of 79 GHz from 5 toThe absolute value of the imaginary part is within the range of 0.5 toThe thickness of the radio wave absorbing lower layer (b) is in the range of 0.10-1.5 mmThe radio frequency reflection upper layer (c) has a real dielectric constant of 2 to 20 at a frequency of 79 GHz.The absolute value of the imaginary part is less thanThe thickness of the radio reflection upper layer (c) is within the range of 0.3 toElectromagnetic wave absorbing sheet for millimeter wave bandAndMillimeter wave band radio wave absorption method using the radio wave absorbing sheetAnd prevention method of radio wave interference.