Microelectromagnetic actuator based on a 3D printing process for fiber scanner application

A novel electromagnetic-actuated fiber scanner has been proposed for ultra-thin scanning fiber endoscope application. A free-fixed optical fiber cantilever with a cylindrical magnet can be driven and vibrated by a tilted coil on a tube surface under electromagnetic force. The tiny coil with a large tilt angle as the actuator is fabricated by a new three-dimensional (3D) printing technology and handmade hybrid process. It is an efficient and low-cost method for fabricating tiny 3D tilted coils compared with the complicated micromachining process. A 2.0 mm outer diameter tilted coil has been successfully developed. The line pitch, tilt angle, resistance and turns of this fabricated coil are 75 μm, 60°, 20 Ω and 100 turns, respectively. The scanning motion of the assembled scanner utilizing the fabricated 3D coil, fiber and a small magnet has been measured by a high-speed camera. The scanner consists of a 9 mm-length optical fiber, a 2 mm outer diameter cylindrical magnet, a jig and a fabricated tilted coil. The displacement of the fiber tip in the scanner is observed and measured when the alternative current-driven voltage was applied to the tilted coil, and 126.8 μm maximum displacement has been obtained. The present fiber scanner with 3D tilted coil has promise for use as an important inspecting device for biomedical endoscope application.