Terahertz polarization imaging with birefringent materials

We present a terahertz (THz) imaging method with a birefringent material which is sensitive to THz wave polarization. The subtle THz polarization modulations introduced by the target are extracted by the amplitudes of the two separated THz peaks passing through the birefringent material. The anisotropy of the industrial sprayed-on-foam-insulation (SOFI) is characterized by measuring its azimuthal angle dependent THz polarization response. This work demonstrated that this polarization sensitive THz imaging technique can be used for industrial inspection and biological related characterization.