<p>This paper presents a novel augmented reality (AR) framework that integrates an advanced optical model to simulate dynamic lighting effects, enabling lifelike day–night cycles and enhancing AR realism. Traditional virtual environments often struggle with real-time, high-fidelity lighting transitions, limiting their effectiveness in applications such as dynamic simulations. To address this, we introduce an animated lighting model that replicates the natural progression of sunlight from sunrise to sunset, creating highly realistic virtual environments. Our framework incorporates six photographic images as AR backgrounds and employs advanced rendering techniques to produce detailed models with high-quality textures and enhanced contrast, particularly in low-light conditions. A progressive lighting algorithm ensures smooth transitions between daylight and nighttime, preserving realism through ambient effects in darker scenarios. At the core of the system is a virtual sun, serving as the primary light source, casting dynamic lighting that enhances the environment’s natural appearance. Depth and intricate surface details are achieved through normal mapping, enriching models without increasing geometric complexity, thereby maintaining efficient performance. Moreover, a texture-sampling-based lighting algorithm dynamically adapts to real-time lighting changes, ensuring seamless transitions and natural interactions between virtual objects and their surroundings. This adaptive approach significantly enhances AR realism, making it well-suited for applications in entertainment, education, and beyond.</p>