| 20090040769 | Free-Form Lenses for Rectangular Illumination Zones - A light source emits light into a solid angle exceeding pi steradians with a known intensity distribution. An illumination lens has a first surface that receives at least 90% of the light of the known intensity distribution and has a shape that transforms the known intensity distribution into an intermediate intensity distribution within the transparent material of the lens. A second surface receives the intermediate intensity distribution and is shaped to transform the intermediate intensity distribution into a final intensity distribution that produces a prescribed illumination distribution upon a rectangular target zone. At least one of the shapes of the first and second surfaces is non-rotationally symmetric and is approximated by a super-ellipsoid. | 02-12-2009 |
