A tubular light source having a semiconductor light source and a tube is disclosed. The tube includes a transparent medium, the tube having a side tube surface, a center curve, one end surface, a length, and a maximum cross-sectional dimension. The tube includes scattering centers that cause light traveling in the tube to be reflected at angles such that the reflected light leaves the tube through the side tube surface. The semiconductor light source is positioned to emit light into the tube within a cone of angles such that the light will not leave the side tube surface in the absence of the scattering centers. The scattering centers can be dispersed in the transparent medium or located on the side tube surface. The transparent medium can be rigid or flexible.