Optical collector designs for enhanced performance of visible light communication receivers

This work presents the design and analysis of an optical collector for improving the sensitivity of optical receivers used in visible light communication systems (VLC). The collector consists of an aspherical lens integrated with an improved coupling structure to enhance the optical power collection captured by the photodetector in the receiver. In addition to this primary design, we also explored cylindrical and compound parabolic concentrator (CPC) configurations for comparative analysis. Through extensive optical simulations and experimental validation using prototypes fabricated with polymethyl methacrylate (PMMA), we demonstrate that our aspherical collector design achieves a maximum optical gain of 8.8× in simulations and ∼5.3× in practical implementations, substantially increasing the optical power available in the photodetector. For performance evaluation, a multi-carrier VLC system was implemented, showing significant improvements in bit error rate (BER) with the aspherical collector design compared to the cylindrical collector, CPC configuration, and the case without any collector (7 × 10^-5, 4.6 × 10^-4, 4.5 × 10^-4, and 1.2 × 10^-3, respectively).