Polymer-based diffractive optical elements for rear end automotive applications: design and fabrication process

Advances in illumination technology in the automotive industry are heading toward the use of coherent sources for adaptable and high-resolution head lamps as well as interior and rear-end lights. We present a cost-effective method to fabricate and design laser-based lighting systems for the rear end in automobiles and other vehicles. The design relies on using binary gratings to generate a desired intensity distribution. For cost-effective fabrication, an optical maskless UV lithography system that employs a spatial light modulator (SLM) for projection of the desired structure onto photoresist is introduced. To replicate the structures onto polymers like poly(methyl methacrylate) (PMMA), we use polydimethylsiloxane soft stamps and a hot embossing system. The experimental results show that the proposed design and fabrication process is promising for high-resolution rear-end lights that might be employed to project symbols or information to guide road users in future.