With the rapid development of application fields such as 5G/6G communication technologies, big data, and artificial intelligence, there is an increasingly urgent demand for new-generation photonic chips. Lithium niobate crystals, due to their excellent electro-optic, nonlinear optical, and piezoelectric properties, have become the core material of the new-generation integrated photonic chips and are known as the “optical silicon”. With the breakthroughs in the preparation and device processing technologies of lithium niobate single-crystal thin films, the single-crystal thin films have demonstrated unique advantages in their applications in high-speed electro-optic modulators, integrated optics, and quantum optics, including smaller size, higher integration, ultrafast electro-optic effect, wide bandwidth, and low power consumption. This paper introduced the research and development progress in the preparation technologies of optical-grade lithium niobate crystals and single-crystal thin films in China and abroad, as well as relevant science and technology policies and their latest applications in fields such as photonic chips, integrated optical platforms, and quantum optical devices. It analyzed the development trends and challenges of the industrial chain of lithium niobate crystals, thin films, and devices and put forward suggestions for the development and future layout of the lithium niobate industry. In China, the research on lithium niobate single-crystal thin films and advanced devices is almost on a par with the international advanced level. However, there is still a large gap in the industrialization of high-quality lithium niobate crystal materials compared with other countries. By optimizing the industrial layout and strengthening basic research and development, China will form a lithium niobate industry cluster covering material preparation, device design, manufacturing, and application in the future.
