A procedure for designing and manufacturing microstructured lenses used in automotive headlamps

Abstract

The transition between the light and dark areas of the luminous intensity distribution of a headlamp needs to fulfil statutory regulations. For projection headlamps, adjusting the transition is done by adding a scattering structure to the lens surface. The requirements for the transition are pointed out, and typical problems are presented. A procedure to create such scattering structures in computer-aided design is shown. Improvements to the controls of turning machines for manufacturing are discussed. A reverse engineering process using a high-precision cylindrical coordinate measuring instrument with an optical probe for quality assurance is presented.