Design of Compact Linear Electromagnetic Actuator for Auto-Focusing in Phone Camera

Abstract

This paper proposes a novel linear electromagnetic actuator (LEA) for auto-focusing of compact phone cameras. An LEA consists of permanent magnets, iron cores, and coils, which are all magnetic circuit components. When coils are powered, induced magnetic field generates N and S poles around iron cores. Thus, unlike voice coil motors (VCMs) that employ the Lorentz force, the motion of the moving part in this study is arisen from a property-same poles repel each other while opposite poles attract each other. When compared to conventional VCM actuators in simulation results, the proposed LEA generates larger force, whereas using smaller current.