Abstract: The present invention describes an “L”-shaped sub-component for a hollow reflective tube used as integrator and/or angle converter for an illumination system. Furthermore, this invention details methods of manufacturing such hollow reflective tubes comprising (1) the steps of forming “L”-shaped sub-components substrates with or without self-alignment and/or mounting features, (2) applying a reflective coating to the inside of said sub-components (3) and assembling said sub-components into hollow tubes. Preferably both sides of the “L”-shaped sub-components have identical spectral and angular dependent coating performance. A particularly suitable method for manufacturing these sub-components substrates is molding them in plastic and over-coating them with a base coating layer to enhance their specular reflectivity.