An apparatus providing a source of shortwave electromagnetic radiation utilizing a tape having a first side and a second side and a laser beam focused and impinging on the first side of the tape. The apparatus utilizes a tape storage unit which delivers or feeds tape from the same. A base supports a first projecting element which contacts the second side of the tape emanating from the storage unit. A second projecting element supported by the base contacts the first side of the tape being fed from the tape storage unit. The portion of the tape between the first and second projecting elements constantly lies in a plane during the feeding of the tape and provides a target surface for a focused laser beam which generates shortwave radiation.