Design of a 5 degree of freedom–voice coil motor actuator for smartphone camera modules

Abstract

Consumers pay most attention to the camera function of smartphones. Thus, manufacturers focus on improving the capabilities of camera modules to deliver clearer and sharper images to consumers. Today, camera modules with auto focusing (AF) and optical image stabilization (OIS) functions are standard in the industry. Specifically, OIS is of the linear movement and rotational movement types. In contrast to the rotational movement type, the commonly used linear movement type cannot compensate for rotational error. Therefore, this paper proposes a novel voice coil motor (VCM) actuator that can supply a 5 degree of freedom (DOF)–compensation that consists of three linear movements and two rotational movements for smartphone camera modules. This novel VCM actuator with 5-DOF compensation is realized using an innovative electromagnetic structure. This paper further verifies the properties of the proposed VCM actuator with a laboratory-built prototype. The experimental results verify the robust properties and feasibility of the proposed VCM actuator.