Imaging tasks in automotive illumination systems and how they are intertwined with photometrics and non-imaging optics

For a long time, imaging optics in automotive lighting played only in the field of -comparably simple - singlet projection lenses for headlamps. In this time, a key focus of automotive illumination optics design was on controlled free-form shapes. With the rise of matrix-headlights, new imaging tasks and specifications came up in automotive optics design. Most recent developments like high resolution micro-LEDs for digital headlighting and near field projection of signaling functions, as well as the use of Micro-Lens- Arrays boost the imaging optics methods in automotive lighting. [1-6] Digital functionality, design aesthetics, energy (optical) efficiency, complementary to mass manufacturability and cost effectiveness are defining the boundary conditions for automotive lighting system design. This paper tries to elaborate an overview of recent imaging tasks in automotive illumination optics design and their related specifications and limitations. Designing the full systems, dense interfunctionality with the light source itself and non-imaging elements plays a key role in meeting design targets. Photometric analysis combines input from light source characteristics, intensity targets and system size. As results, efficiency limitations and imaging system specifications are direct results. These optical design approaches will be demonstrated based on several different application examples: Adaptive Driving Beam matrix headlights as well as projection signals show the specific interaction of imaging subsystems with illumination optics.