[en] An optically pumped polarized H^- source (OPPIS), which is based on the charge exchange between H⁺ ions and electron-spin-polarized alkali atoms has been developed at KEK. Just by applying this scheme to a deuteron beam, it is difficult to obtain a highly vector polarized deuteron beam. To obtain highly vector polarized D^- ions, we have developed a 'dual optical pumping type' of polarized D^- source. With this scheme, a 100% vector nuclear-spin polarization for D^- ions is possible in principle. In a preliminary experiment, a 60% of vector nuclear-spin polarized D^- ions was obtained. (author)