To provide an electromagnetic shield film for reducing a transmissivity of an electromagnetic wave with a particular frequency.
The electromagnetic shield film 1 is configured with a thin metallic or plastic film 2 having conductivity to which slits 3 are formed. The slits 3 are formed in multi-stages and in many columns longitudinally and laterally. By forming the slits 3, a horizontally polarized wave passes through and a vertically polarized wave is shut off. That is, the slits 3 can select a polarized wave to be passed. Moreover, a length L of each slit 3 is selected to be a length for shutting off an electromagnetic wave with a resonance frequency among passed electromagnetic waves (horizontally polarized wave).
Next Patent: RECTENNA APPARATUS