Optical and Visual Performance of PWM Controlled InGaN and InGaAlP LEDs for Automotive Lighting Applications

This research investigates the light quality and thermal management of InGaN and InGaAlP Light Emitting Diodes (LEDs) under various light regulation methods. We compare Continuous Wave (CW) and Pulse-Width Modulation (PWM) modes, examining their impacts on luminous flux, temperature, total color shift, and angular color shift. Our findings reveal that the CW mode offers higher luminous flux and reduced temperatures, while the PWM mode ensures enhanced color stability across different currents and viewing angles, especially for white LEDs; however, this stability does not extend to other LED types. From both optical and visual performance perspectives, the study emphasizes optimizing the driving current to meet regulatory requirements and ensure consistent color perception. These insights are crucial for automotive lighting design, contributing to improved regulatory compliance and aesthetic quality.