In recent years, many double-prism mechanism patents have become promising solutions for precision engineering applications, which can perform superior optical pointing and tracking functions. The paper focuses on surveying recent patents related to rotating double-prism scanner used in the fields of free-space laser communications, laser radar, optical switches, laser scanning, and other precision engineering. A general overview of various rotating double-prism mechanisms is provided, and various aspects of rotating double-prism researches are introduced, including forward problem, inverse problem, drive mechanism, mechanical analysis, error analysis and control system. Patents related to rotating double-prism mechanisms, issued since 2010, are selected for the survey. With a comparison of these patents, some valuable conclusions are drawn to predict the future research and development in rotating double-prism scanner.
Keywords: Beam scanning, control system, mechanical structure, rotating double prisms, scanning mechanism.