A grid polarizer comprising: a transparent substrate made from quartz glass; and a stripe-shaped grid provided on the transparent substrate , the grid including a plurality of linear segments , the grid being made from dielectrics or semiconductors, the grid being having portions that satisfy, in effect, relation of t < T in a periodic fashion, where for each said linear segment of the grid, t represents a first gap between the linear segment concerned and an adjacent linear segment on one side of the linear segment concerned, and T represents a second gap between the linear segment concerned and another adjacent linear segment on an opposite side of the linear segment concerned, wherein the gaps t and T are air gaps, characterized by a ratio of t/T having a value that causes a phase of dense part propagating light to delay at least π/2 for ultraviolet light relative to a phase of a coarse part propagating light, where polarized light that has an electric field component in a length direction of each said linear segment of the grid is s-polarized light, the s-polarized light propagating between two linear segments that are adjacent to each other over the first gap t is the dense part propagating light, and the s-polarized light propagating between two linear segments that are adjacent to each other over the second gap T is the coarse part propagating light, the first gap t being a distance measured at a light exit of the dense part propagating light, the second gap T being a distance measured at a light exit of the coarse part propagating light, wherein the first gap t is from 30 nm to 40 nm and wherein the total of t + T is equal to 140 nm. a transparent substrate made from quartz glass; and a stripe-shaped grid provided on the transparent substrate , the grid including a plurality of linear segments , the grid being made from dielectrics or semiconductors, the grid being having portions that satisfy, in effect, relation of t < T in a periodic fashion, where for each said linear segment of the grid, t represents a first gap between the linear segment concerned and an adjacent linear segment on one side of the linear segment concerned, and T represents a second gap between the linear segment concerned and another adjacent linear segment on an opposite side of the linear segment concerned, wherein the gaps t and T are air gaps, characterized by a ratio of t/T having a value that causes a phase of dense part propagating light to delay at least π/2 for ultraviolet light relative to a phase of a coarse part propagating light, where polarized light that has an electric field component in a length direction of each said linear segment of the grid is s-polarized light, the s-polarized light propagating between two linear segments that are adjacent to each other over the first gap t is the dense part propagating light, and the s-polarized light propagating between two linear segments that are adjacent to each other over the second gap T is the coarse part propagating light, the first gap t being a distance measured at a light exit of the dense part propagating light, the second gap T being a distance measured at a light exit of the coarse part propagating light, wherein the first gap t is from 30 nm to 40 nm and wherein the total of t + T is equal to 140 nm. <EOS>