An　optical　voltage　sensor　for　voltage　linear　measurement　using　radial　polarization　grating　is　designed.　The　electro-optic　phase　delay　in　a　crystal　is　converted　into　a　synchronous　rotation　of　a　ring-shaped　facula.　The　ring-shaped　facula　is　changed　into　a　stripe　facula　by　an　image　converter,　and　then　the　applied　voltage　can　be　measured　by　positioning　the　dark　stripe　center　with　an　image　collecting　system.　The　linear　relation　between　the　electro-optic　phase　delay　and　the　position　of　the　dark　stripe　center　is　proved　using　Jones　matrix.　The　calculation　method　and　the　experimental　verification　of　the　bismuth　germanium　oxide　(BGO)　crystal　and　lithium　niobate　(LN)　crystal　are　given.　The　results　show　that　the　measurement　mode　of　the　designed　optical　voltage　sensor　is　irrelevant　to　the　light　intensity,　and　the　measurable　range　of　the　electro-optic　phase　delay　reaches　172°,　while　the　linear　measurement　for　voltage　is　realized　with　a　measurement　error　less　than　0.5%.　©　2017　Automation　of　Electric　Power　Systems　Press.