In one aspect, an optical system is disclosed. In some embodiments, the optical system includes an optical waveguide, and at least two coupling means forming at least one confocal point being located within the optical waveguide, where a first coupling means of the at least two coupling means has a first focal length, and a second coupling means of the at least two coupling means has a second focal length. In some examples, the first coupling means is configured to couple and/or focus incident light to the optical waveguide, and the second coupling means is configured to emit and/or collimate light conveyed by the optical waveguide.