A Three-element Risley Prism Continuous Scanning System Based on Linear Constraint

Abstract

In the three-element Risley prism system, non-linear errors, the infinite solution, the blind zone and the singularity are primary factors that affect the scanning accuracy of the system. In this paper, an accurate analytical model of the three-element Risley prism system is proposed. To reduce the errors of single-wedge nonlinear constraint equation, a dimensionality reduction method constrained by a single wedge is adopted. In addition, a reliable accuracy of 5mm is employed to achieve a full-area scanning of the system, and a single wedge linear constraint equation with an angular increment is established to control singularities. Simulation results show that the wedge rotation angle curve is stable and continuous in the process of inverse solution, and the full coverage of the scanning area can be achieved by assigning scanning accuracy to 5mm, which indicates that the proposed method can effectively solve the problems and achieve full-area scanning in the system.