Car head lamp has either imaging screen in second focal region to screen part of light spot in this region or optical correction element

摘要

A car head lamp has a light source (10), a reflector (20) with first and second focal regions (F1,F2) and a collecting lens (30). The light source is located at the first focal region, and the focus of the lens lies in the second focal region. The axes of reflector and lens essentially coincide. The head lamp is designed to accommodate, by selection, an imaging screen (40) located in the second focal region to screen a part of the light spot in this region so that the lens projects a light beam with a light/dark boundary. Alternatively the headlamp may be selected to accommodate an optical correction element (50) which can be located between the second focal region and the lens, so that the unit consisting of an optical correction element and a lens, projects a light beam without a light/dark boundary with corrected width.