A multilayer optical polarizing film has optical layers whose refractive
indices substantially match along orthogonal in-plane x- and y-axes, and
that mismatch along a z-axis by at least 0.1 and in some cases by at
least 0.15. The film has substantially no reflection bands at normal
incidence, and for obliquely incident light has at least one reflection
band, for p-polarized light only, that monotonically increases and that
shifts to shorter wavelengths as the incidence angle increases.