To meet the performance requirements for some applications, including small sizes, precise optics, low power consumption and non-electrical control in the devices, an optical fiber scanner using electromagnetic actuation has been developed. This paper acquaints a compact external magnetic field actuated fiber optic scanner, in which the main structure is an optical fiber coated with nickel magnetic gel. The advantages of device architecture are: (1) the scanner dimensions are in the same scales of an optical fiber diameter, (2) optical properties and information are well preserved in the fiber, and (3) the actuation control is external and requires no electrical wiring in scanner design and zero power consumption. In this work, magnetic properties of the nickel based ferromagnetic gel were measured in order to carry out the theoretical calculations of static response and resonant frequencies. With the dynamic waveforms of input and output signals from the position sensing device at both modes of resonant frequencies, we conclude that it is significant to operate at the resonant frequencies so that the scanner requires less power to reach large displacement and the oscillating motion of the scanner is purely sinusoidal. A simple and versatile rotary gel coating technique, static and dynamic performance characterization and potential applications of the fiber scanner will be discussed. Moreover, we will also discuss the practical issues in operation and possible waveform distortion that affects imaging and display quality.

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A compact fiber optic scanner for biomedical applications such as optical coherent tomography has been designed, fabricated and tested. The scanner is designed as an in vivo device and composed of an optical fiber coated with nickelpowder loaded paint for external magnetic actuation. The compactness of the imaging device makes it suitable for applications where size, precision and low power consumption is critical. We have previously demonstrated the principles utilizing magnetic actuation for the fiber scanner coated with magnetic gel. This work focused on verification and optimization of the scanner operation. The magnetic properties of the nickel particle mixed with paint were characterized using an alternating gradient magnetometer. The optical scanner is externally actuated by an electromagnet and so it does not require a voltage or current supply in the probe itself. The displacements of the scanner were recorded using a position sensitive detector. The result showed a 0.8-mm displacement under the influence of a static magnetic field of 17.6 KA/m in a fiber with a moveable length of 4.2cm. Dynamic analysis showed a displacement of 0.83mm with an input current amplitude of 41mA and a magnetic field of 2.4 KA/m. The measurements are in good agreement with the theoretical lumped-element calculations. Finite-element analysis was performed and the results agree with the theoretical and experimental results. The static and dynamic displacements of the fiber optic scanner depend on the thickness and length of the magnetic coating. Thus, scanners for different displacements and operating frequencies can be designed by varying the coating thickness and length.

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Optical second-order nonlinear thin film was developed by doping dye organic molecules in a UV curing epoxy host polymer system and followed by an electric field poling step. The nonlinear optical polymeric thin film fabrication will be described. Results from a systematic evaluation of the film physical and optical properties using AFM, ellipsometer and Maker Fringe will be presented. The film absorption spectrum shows a promising advantage for frequency doubling in the blue color window. Optical nonlinear constants extraction from the Maker Fringe raw data will also be discussed.