## 1 Introduction  
The anticipated sixth generation of wireless communication technology, 6G, represents a paradigm shift in connectivity, aiming to surpass the capabilities of its predecessor, 5G. Envisioned as a transforming force, 6G seeks to provide ultra-fast data rates, incredibly low latency, and unparalleled connectivity, fostering innovations that extend beyond conventional wireless communication boundaries [1]. The technology envisions a seamless integration of diverse communication paradigms, including terahertz frequencies, new waveforms, edge computing, holographic communications, and advanced artificial intelligence [2]. The overarching goal is to create an ecosystem where connectivity is not just pervasive but also intelligent and adaptive to the diverse needs of users. In the pursuit of 6G, the emphasis on continuous innovation becomes paramount. The optimization of resources, efficient spectrum utilization, and sustainable practices are integral aspects that drive the evolution of 6G. Embracing innovation is crucial not only for achieving unprecedented levels of performance but also for addressing the evolving demands of a connected world, ensuring that technological advancements contribute to a more resource-efficient and sustainable future. In that context, the terahertz (THz) band emerges as a promising domain with its vast bandwidth and exceptionally high data rates [3], offering robust support for diverse 6G applications, including wireless data centers [4], ultra-short-distance communications, and other novel scenarios. Optical wireless communications (OWCs) harness various bands within the optical spectrum, comprising infrared (IR), visible light, and ultraviolet (UV) bands, presenting nearly thousands of terahertz of untapped spectral resources. Notably, the visible light band shows several merits, including its eco-friendliness, cost-effectiveness, freedom from spectrum regulation, heightened security, and immunity to electromagnetic interference [5,6]. Particularly in settings where radio frequency (RF) communications encounter limitations, OWCs demonstrate substantial application potential, giving rise to a range of optical communication technologies such as visible light communications (VLC), light fidelity (Li-Fi), optical camera communications (OCC), free space optical (FSO) communications, and light detection and ranging (LiDAR), all being more than relevant for 6G. In the pursuit of 6G technologies, it is imperative to recognize that not all applications demand ultra-high data rates but mainly robustness. In that context, considerations for IoT applications, dedicated industrial use cases, and certain vehicular communications underscore the importance of diverse communication solutions. VLC emerges as a pertinent technology [7]. Unlike bandwidth-intensive applications, VLC offers a balanced and resource-efficient approach for different types of scenarios. Integrating VLC into the portfolio of 6G technologies holds particular relevance for smart cities and industries. Its adaptability, low power consumption, and suitability for specific use cases align seamlessly with the varied communication needs in urban environments and industrial settings. By acknowledging the nuanced requirements of different applications, 6G can position itself as a holistic and inclusive technological ecosystem where innovations like VLC contribute to the optimization of resources and the realization of a technologically advanced yet tailored connectivity landscape. The potential applications of visible light communication (VLC) within the 6G technology landscape are diverse and strategically aligned with the demands of contemporary urban and industrial scenarios, as depicted in Figure 1. Each sector, starting with automotive, exemplifies the adaptability of VLC to meet specific communication needs. In the automotive domain, VLC can leverage LED headlights for vehicle-to-vehicle (V2V) communication, facilitating short warnings and creating communication daisy chains in heavy traffic conditions [8].