Skin disorders such as, for example, atopic dermatitis, dyshidrosis, eczema, lichen planus, psoriasis, and vitiligo, are treated by applying high doses of ultraviolet light to diseased regions of a patients skin. The magnetic recording device includes a planar waveguide having a propagation axis. A plurality of pairs of contacts are in vertical alignment with the circle, and each contacting tooth engages a selected pair of the contacts in a selected rotational position of the actuation member about its vertical axis A.