The device (3A) has layers (18B, 19C) made from ceramic material, plastic, metal or glass, and an optical semiconductor element (7) i.e. LED, formed at a body (6) that encloses an opening. The element emits electromagnetic radiation, and optically conducting, transparent radiation discharge surfaces (8) are formed at a radiation discharging end of the body. A fluid channel (10) is formed in the body and provided for connecting an opening (11) formed at the discharging end with a fluid source e.g. water source, for discharging fluid e.g. water, where the body has a casing surface.
