Electromagnetic resonance coupler

An electromagnetic resonance coupler for transmitting a signal between first resonant wiring and second resonant wiring without contact, the electromagnetic resonance coupler comprising:

• a first substrate;
• and
• a second substrate facing the first substrate,
• wherein the first resonant wiring and first input/output wiring are provided on the first substrate, the first resonant wiring having a loop shape of a predetermined wiring width, and the first input/output wiring being connected to a first connection portion in the first resonant wiring,
• the second resonant wiring and second input/output wiring are provided on the second substrate, the second resonant wiring having the same wiring width and the same shape as the first resonant wiring, and the second input/output wiring being connected to a second connection portion in the second resonant wiring,
• when viewed in a direction perpendicular to a main face of the first substrate, the first resonant wiring and the second resonant wiring are symmetric with respect to a point, and contours of the first resonant wiring and the second resonant wiring match,
• a distance between the first resonant wiring and the second resonant wiring in the direction perpendicular to the main face of the first substrate is less than or equal to one half a wavelength of the signal, and
• a wiring length from an outer end of the first resonant wiring to the first connection portion is longer than a wiring length from an inner end of the first resonant wiring to the first connection portion and is less than or equal to one half a wiring length of wiring that is routed along an outermost periphery of the first resonant wiring.