A lens (1) comprising a centrally extending axis (A) being perpendicular to a lens axis (L) of the lens, the lens being adapted for retracting light rays from a light source positioned off-axis with respect to the centrally extending axis, the lens comprising a first plurality of slits (21, 22, 23, 24) extending entirely in an interior of the lens and comprising a length (l) extending perpendicular to the centrally extending axis, a width (w) extending parallel to the centrally extending axis and a thickness (t) extending perpendicular to both the length and the width, the first plurality of slits being mutually parallel and covering between 40% and 60% of a plane in which both the centrally extending axis (A) and the length (l) and width (w) of the first plurality of slits (21, 22, 23, 24) extend.