Browsing by Author "Huang, J. -S."

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A novel lens cap designed for the RGB LEDs installed in an ultra-thin and directly lit backlight unit of large-sized LCD TVs
(2008-02-01)
Chao, Paul C-P.
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Shen, C. -Y.
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Chiu, C. -W.
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Huang, J. -S.
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Kao, Y. -Y.
The objective of this study is to design a novel cone-shaped lens cap on LEDs in order to achieve high optical efficiency in an ultra-thin directly lit RGB LED backlight unit (BLU) for large-sized LCD TVs. The use of the novel lens cap could play the role of a diffuser, a low light-efficiency component in a BLU, in order to gain higher efficiency and simultaneously provide satisfactory uniformity in light distribution. The novel cone-shaped lens is coated with aluminum on the outside surface of the cone for mirroring effects to reflect most of the LED emitted light horizontally and then reflect the light at the BLU boundaries, and then, finally to the output plane. In this way, bright spots on the output plane of the BLU can be avoided, leading to increased uniformity. Simulations were conducted to design and optimize varied aspects of the designed lens and BLU, including the cone angle of the proposed lens and the LED spacing (pitch). To further achieve color balance, a known Genetic Algorithm is used to search for the optimal angular placement of each RGB LED, resulting in better color balance. Finally, a prototype BLU for large-sized 37-in. LCD TVs with the proposed lens was built to verify the expected performance.
Achieving color balance of a large sized BLU directly-lit by LEDs capped with customized optical lenses
(2008)
Chao, Paul C. -P.
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Shen, C. -Y.
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Chiu, C. -W.
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Huang, J. -S.
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Wang, C-L.
The objective of this study is to develop a high color balance thin RGB LED backlight unit (BLU) for large-sized LCD-TVs. Genetic Algorithm is employed to search the optimal angular placement of each RGB LED and gain the condition of better color mixing for achieving high color balance of BLU.
Design and construction of an in situ inspection machine for ensuring the dynamic performance of fluid bearings in data storage devices
(2009-10-01)
Chao, Paul C. -P.
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Chiu, Chi-Wei
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Huang, J. -S.
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Chen, Chien-Ming
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電控工程研究所
The objective of the study is to design and construct an in situ inspection machine that would be used to evaluate the dynamic performance of the small-scaled hydrodynamic journal bearings used often for data-storage devices. To this end, novel design ideas of using a high-stiffness air bearing and suspending the test bearing by the specially-designed fixture frame are first proposed, which are accompanied by the special requirements in the manufacturing precisions for various dimensions and geometry characteristics of the components of the experiment system. The capacitor-type sensors, including two custom-mades are next utilized to measure the motions of the spindle and bearing. Finally, a calculating algorithm for deriving performance parameters of the test bearing are proposed, which is intended primarily to estimate rotor stiffness coefficients, load capacity, and eccentricity ratio to determine if the test bearing meet the dynamic performance expected by the original design.
Fabrication of self-assembled spherical Gold Particles by pulsed UV Laser Treatment
(2018-07-26)
Schmidl, G.
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Jia, G.
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Gawlik, A.
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Kreusch, J.
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Schmidl, F.
We report on the fabrication of spherical Au spheres by pulsed laser treatment using a KrF excimer laser (248 nm, 25 ns) under ambient conditions as a fast and high throughput fabrication technique. The presented experiments were realized using initial Au layers of 100 nm thickness deposited on optically transparent and low cost Borofloat glass or single-crystalline SrTiO3 substrates, respectively. High (111)-orientation and smoothness (RMS approximate to 1 nm) are the properties of the deposited Au layers before laser treatment. After laser treatment, spheres with size distribution ranging from hundreds of nanometers up to several micrometers were produced. Single-particle scattering spectra with distinct plasmonic resonance peaks are presented to reveal the critical role of optimal irradiation parameters in the process of laser induced particle self-assembly. The variation of irradiation parameters like fluence and number of laser pulses influences the melting, dewetting and solidification process of the Au layers and thus the formation of extremely well shaped spherical particles. The gold layers on Borofloat glass and SrTiO3 are found to show a slightly different behavior under laser treatment. We also discuss the effect of substrates.
Novel lens design for ultra-thin, high efficiency of light utilization, direct type RGB LED backlight module
(2007-01-01)
Shen, C. -Y.
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Chiu, C. -W.
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Chao, Paul C. -P.
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Huang, J. -S.
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Wang, C. L.
The objective of this study is to design a novel cone-shaped lens for achieving high optical efficiency for an ultra-thin, direct type RGB LED backlight unit (BLU). The usage of the novel lens could replace the commonly used diffuser plate for gaining higher efficiency and providing satisfactory uniformity of BLU. FMC7- 2