An electromagnetic wave detection apparatus comprising: a first propagation unit that includes a reference surface and a plurality of pixels positioned along the reference surface and causes electromagnetic waves incident on the reference surface to propagate in a particular direction using each of the pixels; a first detector that includes a first detection surface and detects electromagnetic waves incident on the first detection surface; and a second propagation unit that includes a first surface opposing the reference surface, a second surface opposing the first detection surface, and a third surface intersecting the first surface and the second surface and on which reflected waves reflected by a detection object of electromagnetic waves radiated from an irradiator are incident, wherein the first surface causes electromagnetic waves propagating in a second direction to be incident on the reference surface, the first surface causes electromagnetic waves re-incident from the reference surface to propagate in a third direction intersecting the third surface, the third surface causes electromagnetic waves propagating in the third direction to propagate in a fourth direction intersecting the second surface, the second surface emits electromagnetic waves propagating in the fourth direction to the first detection surface characterized in comprising a second detector that includes a second detection surface and detects electromagnetic waves incident on the second detection surface; wherein the third surface separates electromagnetic waves propagating in a first direction intersecting the third surface into electromagnetic waves to be reflected by the third surface and incident on the second detector and electromagnetic waves to propagate in the second direction intersecting the first surface. a first propagation unit that includes a reference surface and a plurality of pixels positioned along the reference surface and causes electromagnetic waves incident on the reference surface to propagate in a particular direction using each of the pixels; a first detector that includes a first detection surface and detects electromagnetic waves incident on the first detection surface; and a second propagation unit that includes a first surface opposing the reference surface, a second surface opposing the first detection surface, and a third surface intersecting the first surface and the second surface and on which reflected waves reflected by a detection object of electromagnetic waves radiated from an irradiator are incident, wherein the first surface causes electromagnetic waves propagating in a second direction to be incident on the reference surface, the first surface causes electromagnetic waves re-incident from the reference surface to propagate in a third direction intersecting the third surface, the third surface causes electromagnetic waves propagating in the third direction to propagate in a fourth direction intersecting the second surface, the second surface emits electromagnetic waves propagating in the fourth direction to the first detection surface characterized in comprising a second detector that includes a second detection surface and detects electromagnetic waves incident on the second detection surface; wherein the third surface separates electromagnetic waves propagating in a first direction intersecting the third surface into electromagnetic waves to be reflected by the third surface and incident on the second detector and electromagnetic waves to propagate in the second direction intersecting the first surface.