Design and analysis of angle sensor optical parameters

The principle and characteristics of an optical critical angle sensor based on the internal-reflection effect are described. Then, the method to design the optical parameters of the critical angle prisms and the relationships between these parameters and the system character are discussed with analytical and simulation results. These parameters include the initial angle of incidence, non-parallelism errors of the two parallel faces, and the surface flatness of the reflection faces. A pair of custom-built critical angle prisms providing three internal-reflections is used in our simulation.