Patent ID: 8162504

Claim:
An illumination system, comprising: a light source; and a reflector having a focal point, the reflector including: a first optical interface adjacent the light source which redirects light emitted from the light source and incident on the first optical interface via Fresnel reflection; and a second optical interface adjacent the first optical interface on a side opposite the light source, which reflects light passing through the first optical interface via total internal reflection back towards the first optical interface, wherein the reflector includes an optically transparent material which is curved in relation to the focal point with the light source located proximate the focal point, the optically transparent material having a flat surface on one side which forms a part of the first optical interface and redirects the light emitted from the light source via the Fresnel reflection toward the focal point, and a surface having a prism structure on an opposite side forming a part of the second optical interface to totally internally reflect the light passing through the first optical interface back towards the first optical interface and the focal point, and wherein the light source is a linear light source and the reflector runs parallel the linear light source, and the prism structure comprises parallel grooves which run in a direction orthogonal to an axis of the linear light source.