Patent attributes
Apparatus and method for focusing light from an extended light source onto a secondary focal point (such as an input end of a light guide element). The apparatus includes a solid conic body formed in accordance with an ellipse, off axis paraboloid, or other conic shape, within which is disposed a refractive focusing lens. A first portion of the light rays (i.e. high angle light rays) generated by the extended light source are reflected through total internal reflection (TIR) by a first portion of the solid conic body onto the secondary focal point. A second portion of the light rays (i.e., low angle light rays), which would otherwise not be reflected by the solid conic body, are refracted by the focusing lens onto the same secondary focal point. Thus, by superposition, substantially all of the optical energy from the extended light source is coupled onto the secondary focal point.