US Patent 7549783 Efficient luminaire with directional side-light extraction

Luminaire with directional side-light extraction comprises a light pipe with a light-carrying core, and with a light-extraction structure along a first longitudinal side of the luminaire, confined to a radial swath of the luminaire, along the longitudinal axis of the luminaire, of substantially less than 180°. The second end of the light pipe has light-saving means for directing saved light from the second end towards the first end. The light-extraction means is adjustable to accommodate angular distributions of light from various light sources.