Polarization-resolved　photodetection　in　a　compact　footprint　is　of　great　interest　for　ultraminiaturized　polarimeters　to　be　used　in　a　wide　range　of　applications.　However,　probing　the　states　of　polarization　(SOP)　in　materials　with　natural　anisotropy　are　usually　weak,　limited　by　the　material＇s　natural　dichroism　or　diattenuation.　Here,　a　twisted　unipolar-barrier　van　der　Waals　heterostructure　(vdWH)　to　construct　a　bias-switchable　polarization　detection　for　retrieval　of　full　SOP　(from　0　to　180　degrees)　for　linear　polarized　incident　light　is　reported.　As　a　demonstration　example,　this　study　realizes　the　concept　in　a　b-AsP/WS2/b-AsP　vdWH　relying　on　the　natural　anisotropic　properties　of　the　materials　without　using　additional　plasmonic/metasurface　nanostructures　to　realize　linear　polarimetry　in　the　mid-infrared　range.　Polarimetric　imaging　is　further　demonstrated　with　the　developed　linear　polarimetry　by　directly　displaying　the　Jones-vector-described　SOP　distribution　of　certain　target　object.　This　method,　with　the　capabilities　of　detecting　full　linear　SOP,　is　promising　for　the　next-generation　on-chip　miniaturized　polarimeters.