A pseudo sheet structure is usable for a sensor configured to emit an electromagnetic wave in a band ranging from 20 GHz to 100 GHz. The pseudo sheet structure includes a plurality of conductive linear bodies arranged at an interval L satisfying a formula (1) below, 0.034×λS≤L≤20 mm (1). In the formula (1), L is the interval between the plurality of conductive linear bodies, λS is a wavelength of the electromagnetic wave emitted by the sensor, and a unit for each of L and λS is mm.