An optical polarization beam combiner or separator device includes a first optical beam carrier for carrying a first polarized beam and a second optical beam carrier for carrying a second polarized beam whose polarization is orthogonal to the polarization of the first polarized beam. First and second collimating/focusing lenses are positioned between the first and second optical carriers. A third optical beam carrier for carrying a non-polarized beam positioned on the same side of the two collimating/focusing lenses as the first optical beam carrier. An inorganic, dielectric grid polarizer is disposed between the first and second collimating/focusing lenses, and includes a stack of film layers disposed over a substrate. Adjacent film layers have different refractive indices. At least one of the film layers is discontinuous to form a form birefringent layer with an array of parallel ribs with a pitch of less than 400 nm, and greater than 200 nm.