Wire grid polarizer and manufacturing method thereof

The invention provides a wire grid polarizer and a manufacturing method thereof. The wire grid polarizer comprises an absorbing layer and a metal wire grid, wherein the absorbing layer comprises a base plate, multiple first bulge parts arranged on the upper surface of the base plates at intervals, aluminium wires arranged on the surfaces of the first bulge parts, and silicon dioxide layers; the metal wire grid comprises flat layers, aluminium layers arranged on the flat layers, and second bulge parts arranged on the upper surfaces of the aluminium layers at intervals; the surfaces of the silicon dioxide layers are coated with the flat layers; the second bulge parts are adopted to etch the aluminium layers so as to form a grating structure. Compared with the prior art, the overlapped double-grating structure can improve the visual angle defects of the existing wire grid polarizer and also can eliminate the bad situation of dark state light leakage.