Optimization of diffractive optical elements for automotive adaptive front-lighting systems: compliance with ECE-R123

This study investigated the design and implementation of an adaptive front-lighting system (AFS) utilizing diffractive optical elements (DOEs) for automotive applications, addressing challenges found in conventional headlamp systems such as bulkiness, assembly complexity, and mechanical vulnerability. Key DOE parameters, including pixel size, depth, and phase shift, were optimized to achieve compliance with ECE-R123 while high optical performance and compactness were maintained. Simulations were conducted using VirtualLab Fusion (VLF) to achieve target illumination patterns by precisely controlling pixel dimensions, diffraction efficiency, and phase distribution. This ensured that key measurement points (e.g., B50L and 75R) met the stringent ECE-R123 requirements. Fabricated DOEs underwent structural evaluation via scanning electron microscopy (SEM) and optical performance assessments using a high precision goniophotometer. The experimental results demonstrated successful adherence to ECE-R123 standards, characterized by accurate cut-off lines and uniform illumination distributions. The findings underscore the DOE's potential as a replacement for conventional complex lens systems, emphasizing advantages such as reduced weight, planar architecture, and enhanced design flexibility. This research presents a scalable and efficient solution for automotive AFS, promoting improved safety and adaptability across various driving conditions.