Terahertz Single Pixel Imaging Via Spatial Polarization Modulating Masks

Terahertz single pixel imaging is rapidly evolving to meet innovations in spatial terahertz modulation. The work presented here demonstrates a novel modulation scheme for terahertz frequencies involving the direct spatial modulation of the imaging beam polarization. This is realized by the design of modulation masks that incorporate wire-grid polarizers as each modulating pixel to probe the polarization response of an object. The wire-grid polarizer masks are constructed by preparing parallel wires of aluminum film on polyethylene by laser ablation. In this work, five-by-five pixel polarization-sensitive images of an object are reconstructed by a compressive imaging method to demonstrate the feasibility of using spatial polarization modulation to conduct polarization-resolved terahertz single pixel imaging. This modality gives access to polarization-resolved images using terahertz detection configurations which are less complex with faster image acquisition relevant to terahertz material inspection via polarization-resolved imaging.