The emergence of OEM and industry benchmarks [1-6] raised the expectation regarding automotive headlamps performance in the last decade, resulting in growing benefits regarding traffic safety. Concomitantly, designing headlamps has grown in complexity, especially for low beam and high beam applications. Fulfilling all requirements concurrently is challenging, not merely due to the large number of requirements to keep track off during development, but predominantly due to the simultaneous inclusion of lamp- (luminous intensity) and vehicle-based (illuminance) metrics in the design. In this paper we propose and demonstrate an alternative design methodology for the development of forward lighting systems with the goal of reducing development time, providing superior photometry, and providing more structure to the development process. Instead of iteratively adjusting optical surfaces and running subsequent simulations to validate each design step, checking whether the change could achieve the respective design objective, we are subdividing the overall design problem into multiple steps and solve multiple inverse problems instead. Specifically, we compile all requirements into a unified set of luminous intensity requirements. Subsequently, we create analytical light distributions that meet this total set of requirements. Once validated, the resulting target light distribution is fragmented into multiple light distributions, which are then used as individual design targets for the creation of freeform surfaces in support of each optical sub-component. The total light distribution is obtained by superposition of all partial light distributions.
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