Radiation source configured for obliquely launching a narrowband electromagnetic radiation , comprising: an emitter structure having a main radiation emission region (14-1) for emitting the narrowband electromagnetic radiation , and a layer element coupled to the main radiation emission region (14-1) of the emitter structure , wherein the layer element comprises a radiation deflection structure configured for deflecting the radiation emission characteristic of the emitter structure with respect to the surface normal (N) of the main radiation emission region (14-1) of the emitter structure , wherein the radiation deflection structure of the layer element comprises a plurality of light directing elements , wherein the orientation of the light directing elements is angularly offset with respect to a surface normal of the main radiation emission region (14-1) of the emitter structure , wherein the light directing elements are formed as inclined transparent channels separated by optically opaque or reflecting interlayers , wherein the transparent channels and the optically opaque or reflecting interlayers are arranged in an alternating and adjacent configuration, or wherein the light directing elements comprise transparent regions and opaque or reflective wall regions , wherein the transparent regions and the opaque or reflective wall regions are arranged in an alternating and adjacent configuration. an emitter structure having a main radiation emission region (14-1) for emitting the narrowband electromagnetic radiation , and a layer element coupled to the main radiation emission region (14-1) of the emitter structure , wherein the layer element comprises a radiation deflection structure configured for deflecting the radiation emission characteristic of the emitter structure with respect to the surface normal (N) of the main radiation emission region (14-1) of the emitter structure , wherein the radiation deflection structure of the layer element comprises a plurality of light directing elements , wherein the orientation of the light directing elements is angularly offset with respect to a surface normal of the main radiation emission region (14-1) of the emitter structure , wherein the light directing elements are formed as inclined transparent channels separated by optically opaque or reflecting interlayers , wherein the transparent channels and the optically opaque or reflecting interlayers are arranged in an alternating and adjacent configuration, or wherein the light directing elements comprise transparent regions and opaque or reflective wall regions , wherein the transparent regions and the opaque or reflective wall regions are arranged in an alternating and adjacent configuration. wherein the light directing elements are formed as inclined transparent channels separated by optically opaque or reflecting interlayers , wherein the transparent channels and the optically opaque or reflecting interlayers are arranged in an alternating and adjacent configuration, or wherein the light directing elements comprise transparent regions and opaque or reflective wall regions , wherein the transparent regions and the opaque or reflective wall regions are arranged in an alternating and adjacent configuration. <EOS>