Temperature dependence of the imaging properties of holographic lenses

The demand for advanced photonic technologies to enhance augmented reality (AR) devices has led to a significant interest in new optical materials suitable for operation in sometimes challenging environmental conditions, such as elevated temperatures levels. Holographic optical lenses (HOLs), fabricated using holographic recording, offer several advantages over traditional refractive lenses, including greater versatility, lower cost, lower weight, and increased adaptability. In this study, we investigated the optical and thermal performance of HOLs recorded on four different photosensitive materials: Bayfol HX200, Bayfol HX120, a PVA/acrylamide-based photopolymer (AA/PVA), and a photopolymerisable hybrid sol–gel (PHSG). The lenses were exposed to thermal cycles 20^∘C–100^∘C–20^∘C to simulate real-world conditions in AR systems, where heat generation from processors, sensors, displays, and the proximity to poweful LED light sources can affect their optical performance. The results highlight that Bayfol HX200 showed the highest thermal stability, while the PHSG demonstrated good recovery properties after thermal stress. Optical and image quality were evaluated using parameters such as root mean square wavefront error, Strehl ratio and spatial resolution, which revealed significant variations in lens performance as a function of temperature. These results provide valuable information on the material selection for durable, high-performance holographic lenses in AR applications.