Abstract: A periscope having parallel reflecting end faces each at an angle less than 45.degree. to parallel inlet and outlet faces of the prism combination. Light entering, for example, the inlet face at the region of one inclined face, is reflected four times within the prism combination. Two reflections occur at each of the inclined faces, and two reflections occur along portions of the inlet and outlet faces between the inclined end faces, so that the optical path through the periscope takes the form of a zig-zag or broken line multiple reflection path. Plano-concave cylindrical eye-piece lenses can be provided at the light inlet and light outlet regions of the inlet and outlet faces. Convex cylindrical diopters, facing each other, can be provided between the adjacent ends of the prisms.