Browsing by Author "Yang, BW"

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Carrier-to-noise ratio improvement with pulsed-laser readout on magnetically induced superresolution by center aperture detection disks
(1999-09-01)
Chen, BM
;
Yang, BW
;
Hwang, WK
;
Shieh, TE
;
Shieh, HPD
Magnetically induced superresolution by center aperture detection (MSR-CAD) using pulsed and conventional de schemes were applied to magneto-optical disks to quantitatively evaluate readout performances. By simulation and experiments, it was found that carrier-to-noise ratio (CNR) in the pulsed-laser readout was about 2.5 dB higher than that in the de readout scheme at mark size of 0.45 mu m or shorter, Therefore, pulsed readout is feasible to improve CNR and recording density in MSR-CAD disks.
Interlayer cross talk in dual-layer read-only optical disks
(1999-01-10)
Yang, BW
;
Shieh, HPD
;
光電工程學系
;
Department of Photonics
Volumetric optical disks comprising multiple data layers have been proposed to multiply recording density. Owing to the presence of out-of-focus data layers, interlayer cross talk is induced in readout. An optical model was developed to study the readout process and the effect of interlayer cross talk on the readout of dual-layer read-only optical disks. Schemes to improve the readout characteristics by suppression of the interlayer cross talk were proposed. Experiments that agreed well with the simulation resulted. (C) 1999 Optical Society of America.
Readout scheme by pulsed irradiation center aperture detection on magnetically induced super resolution magnetooptical disks
(1996-01-01)
Yang, BW
;
Hwang, WK
;
Shieh, HPD
;
交大名義發表
;
光電工程學系
Magnetically induced super resolution (MSR) is used to read ''below-diffraction-limit'' recording marks on magneto-optical (MO) media. A nanosecond-order laser pulse irradiated onto MO media can create a quasicircular temperature profile, thereby yielding a quasi-circular sub-mu m aperture to effectively derive a readout signal from sub-mu m marks recorded on the disks. In this study, the pulsed irradiation and conventional DC readout methods are applied to a MO disk with a center aperture detection (CAD) structure to quantitatively evaluate their readout performance. The size and shape of the effective aperture, jitters due to readout parameters; and aperture wall width generated are studied. The feasibility of the pulsed irradiation readout is then assessed.
The characteristics of a dual-layer optical disk with read-only and erasable functions
(1998-09-01)
Yang, BW
;
Shieh, HPD
;
光電工程學系
;
Department of Photonics
A dual-layer optical disk comprised of a read-only layer and a phase-change layer was designed to perform the read-only and erasable dual-functionality in an optical disk. With the properly designed dual-layer disk structure, 23 mW of write power was adequate to write data marks on the erasable phase-change layer; simultaneously, equal magnitude of sufficient radiofrequency readout signals could be obtained on both its data layers. The analyzes of its recording characteristics demonstrated the feasibility of the dual-functional optical disk.