Hyo-Chang Kim

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We provide an experimental demonstration of novel form-birefringent computer-generated holograms at wavelengths of 1.55 and 10.6 microm. These novel devices utilize a 2-D array of cells that can be fabricated with a single lithographic step. Each cell contains a subwavelength binary grating whose orientation controls the desired continuous phase profile(More)
Resonant filters in waveguides with vertical gratings have been realized on a silicon-on-insulator wafer. Two identical uniformly distributed Bragg reflectors with vertical gratings are separated by a quarter wavelength phase offset. Experimental studies show a broad stopband and a narrow transmission band which shifts with changing substrate temperature(More)
We report the analysis, design, fabrication and experimental characterization of novel subwavelength computer-generated holograms that produce uniform symmetric spot array. We distinguish between a polarization-sensitive and polarization-insensitive far-field reconstruction and show that a linearly polarized incident illumination is required in the former(More)
Transmission resonant filters in a waveguide with vertical gratings have been realized in silicon on insulator wafers. Experimental studies of fabricated devices show a broad stopband of approximately 19 nm in the center of which exists a narrow transmission band of approximately 0.5 nm with a quality factor of approximately 3000. These resonant cavities(More)
Pituitary abscess is a rare and potentially lethal condition. Pituitary abscess in a pregnant woman has not been previously described. A 38-year-old pregnant woman (34 weeks gestation) with a pituitary mass complained of a progressive headache and sudden visual impairment. She was afebrile and had no inflammatory symptoms on admission. On MRI, the(More)
Smart Home is an application of Information Communication Technologies (ICT) in living environment. The concept of smart home has received interests as future solution for the elders and disabled to enhance quality of life. The long-term objective of this study is to design accessible Smart Home for the elders. And a key element to design accessible Smart(More)