One method for influencing the polarization of light is the use of wire-grid polarizers. For the visible region, this type of element can be realized as a metal-stripe grating with periods less than the wavelength. We fabricate metal-stripe gratings with periods down to 190 nm in thin chromium layers of 35-nm thickness using electron-beam lithography and ion-beam etching. A detailed investigation of the influence of grating period and duty cycle on the polarization effect is carried out to verify the conformity of rigorous diffraction theory and experimental results. The comparison between the two indicates good performance. Polarization ratios of the order of 5 with transmission efficiencies of about 60% in TM polarization are obtained. The connection of the polarization effect realizable and the fabrication technology used is discussed.