Kah How Koh

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A novel dynamic excitation of an S-shaped PZT piezoelectric actuator, which is conceptualized by having two superimposed AC voltages, is characterized in this paper through the evaluation of the 2-D scanning characteristics of an integrated silicon micromirror. The device is micromachined from a SOI wafer with a 5 μm thick Si device layer and multilayers of(More)
Aluminium-coated micromirrors driven by electrothermal and electromagnetic actuations have been demonstrated for 3-D variable optical attenuation applications. Three types of attenuation schemes based on electrothermal, electromagnetic and hybrid, i.e. combination of electrothermal and electromagnetic, actuations have been developed. In addition, two(More)
Grating structures are designed at the inner wall of the Fabry-Perot (FP) resonator to enhance the performance of an FP optical filter. The rectangular grating or triangular grating (TG) structures allows the light to be propagated effectively through the FP resonator. Attributed to the grating structures, the spectrum intensity of a FP resonator with(More)
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