Protection of glass against counterfeiting: A review of modern optical techniques

Glass is a versatile material with exclusive features, making it ideal for diverse applications. However, counterfeiting in glass products is a growing concern, especially in industries where quality and authenticity are crucial. Advancements in optical technologies including luminescent materials and novel labeling techniques enhance security and authenticity of glass products, addressing the challenges posed by counterfeiting. The article navigates through the key glass synthesis methods including melt-quenching, sol-gel, and electrospinning, emphasizing their role in improving authentication of genuine glass products. Further, this review explores the current trends in the anti-counterfeiting strategies for glass, highlighting the diverse optical approaches that leverage ultraviolet / near-infrared emissions, heating, laser-induced localized crystallization, etc. to unveil the concealed features. Moreover, the potential of glass as an optical data storage medium is also examined. Furthermore, the article addresses the key challenges associated with implementing optical security features in glass and discusses future research opportunities to enhance the existing techniques.