Described is an optical waveguide having a main direction of extension, at least one radiation entrance face, and a radiation exit face that extends longitudinally to the main direction of extension, wherein at least one radiation entrance face extends transversely to the main direction of extension, and the at least one radiation entrance face has two convexly curved subregions that are connected to each other by a kink-like or concavely shaped indentation. An optical device formed with such a waveguide is also described, as is a display device.