Browsing by Author "Yang, Bo-Ru"

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A Novel Architecture for Autostereoscopic 2D/3D Switchable Display Using Dual Layer Strip Patterned OLED Backlight Module
(2014-05-01)
Wang, Yi-Jun
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Liu, Jun
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Tan, Jian
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Yang, Bo-Ru
;
Ding, Wei-Xian
A novel backlight module that integrates dual layer strip patterned organic light emitting diode (DLSP-OLED) for 2D/3D switchable display was demonstrated. The DLSP-OLED functions as a parallax barrier in 3D mode and a planar light source in 2D mode. The results indicated that the backlight module with a thin form factor (similar to 1.1 mm) can achieve uniformity of 91% in 2D mode, and increased optical efficiency by a factor of 2.8 with a crosstalk of less than 6% in 3D mode, compared with the conventional 2D/3D switchable display. A fast switching rate (<1 ms) with simple operation can eliminate the visual fatigue caused by flicker during the switching. In addition, this configuration can function localized 3D display by modulating the DLSP-OLED individually.
A novel pixel circuit compensating for poly-Si threshold-voltage shift and degradation of OLED for emi-flective display
(2007)
Lin, Kun-Yueh
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Yang, Bo-Ru
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Shieh, Han-Ping D.
;
光電工程學系
;
Department of Photonics
A novel pixel circuit design of poly-silicon backplane for emi-flective display that integrated a reflective liquid crystal display (R-LCD) and a top-emission organic emitting diode (TOLED) was proposed. The pixel circuit could compensate both the threshold voltage shift of poly-silicon transistors and the turn-on voltage shift of TOLEDs.
Blue Phase LC/Polymer Fresnel Lens Fabricated by Holographics
(2014-02-01)
Tan, Jian
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Song, Yue
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Zhu, Ji-Liang
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Ni, Shui-Bin
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Wang, Yi-Jun
A novel fabrication method using holographic exposure for switchable blue phase (BP) liquid crystal (LC)/polymer Fresnel lens was demonstrated. The Fresnel pattern can be achieved by interfering a planar and a spherical wave fronts with a 532-nm laser. The BPLC/polymer Fresnel lens can thus be fabricated without photo mask and controlled with a simpler driving compared with the conventional LC Fresnel lens.
Electrically robust silver nanowire patterns transferrable onto various substrates
(2016)
Liu, Gui-Shi
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Liu, Chuan
;
Chen, Hui-Jiuan
;
Cao, Wu
;
Qiu, Jing-Shen
We report a facile technique for patterning and transferring silver nanowires (AgNWs) onto various substrates. By employing only UV/O-3 and vapor treatment of hexamethyldisilazane (HMDS), we are able to accurately manipulate the surface energy via alternating the terminal groups of a polydimethylsiloxane (PDMS) substrate, so as to assist selective formation and exfoliation of AgNW films. A simple UV/O-3 treatment on PDMS enables uniform, well-defined, and highly conductive patterns of AgNWs after spin-coating. A vapor treatment of HMDS lowers the surface energy of the oxidized PDMS so that the patterned AgNWs embedded in an epoxy resin (EPR) are cleanly transferred from the PDMS to the target substrate. It is found that the AgNW-EPR composite on polyethylene glycol terephthalate (PET) exhibits remarkable durability under the bending test, tape test, ultrasonic treatment in water, and immersion of chemical solvents. In addition, we demonstrate that the AgNW-EPR composite work well as conductive patterns on the oxidized PDMS, polyvinyl alcohol (PVA), paper, and curved glass. The facile technique extends the applicability of AgNWs in the field of electronics, and it is potentially applicable to other nanomaterials.
Emi-flective display device with attribute of high glare-free-ambient-contrast-ratio
(2007-11-01)
Yang, Bo-Ru
;
Hsu, Chuan-Wei
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Shieh, Han-Ping D.
;
光電工程學系
;
顯示科技研究所
We have demonstrated the integration of an organic light emitting device (OLED) and a reflective liquid crystal display (R-LCD) which was termed an emi-flective display. The glare-free-ambient-contrast-ratio (GFA-CR) was used to evaluate the image quality of display devices under ambient light. Through integrating the OLED with R-LCD, the GFA-CR of the device achieved an improvement by a factor of 8 compared with that of the OLED alone. Moreover, the integrated R-LCD showed a GFA-CR of 100 : I within a viewing cone of 20 degrees which can suppress the wash-out of OLED and is more power-saving in the sunlight. Therefore, an emi-flective display is a promising technique for mobile applications.
Emillective display with integration of reflective liquid crystal display and organic light emitting diode
(2007-01-01)
Yang, Bo-Ru
;
Liu, Kang-Hung
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Shieh, Han-Ping D.
;
光電工程學系
;
顯示科技研究所
A novel emi-flective display which integrates a reflective liquid crystal display (R-LCD) and an organic light emitting diode (OLED) was demonstrated, whose OLED achieved a gain factor of 8 in contrast ratio (CR) compared with the conventional OLED. Under the high light ambience, the R-LCD is sustained with the CR of 10:1 at the viewing angle between +/- 55 degrees; while in the dim ambience, the OLED is operated with the CR of 5000 : 1 at +/- 50 degrees. By replacing the backlight system with OLED, emi-flective display has the benefits of lighter weight (< 90%), thinner form factor (< 40%), and lower power consumption (< 2%, under sunlight) compared with the conventional LCD; therefore, to be very applicable for mobile products.
Enhancement of Electroactive Phases of PVDF by Mixing SiC Nanowires for Pressure Sensing
(2016)
Huang, Jiefang
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Han, Songjia
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Chen, Hui-Jiuan
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Luo, Zhenhua
;
Shieh, Han-Ping D.
Poly(vinylidene fluoride) (PVDF) is one of the ideal materials for wearable pressure sensing owing to its excellent piezoelectric property, good flexibility, and easy fabrication processing. In this work, we mixed PVDF matrix with silicon carbide (SiC) nanowires acting as an efficient nucleating agent to transform the non-polar a phase to polar beta and gamma phases to improve the crystallinity of electroactive phases and enhance the piezoelectricity of PVDF thin film.
Enhancement of Polar Phases in PVDF by Forming PVDF/SiC Nanowire Composite
(2016-12)
Huang, Jie-Fang
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Han, Song-Jia
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Chen, Hui-Jiuan
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Liu, Gui-Shi
;
Li, Gong-Tan
Different contents of silicon carbide (SiC) nanowires were mixed with Poly(vinylidene fluoride) (PVDF) to facilitate the polar phase crystallization. It was shown that the annealing temperature and SiC content affected on the phase and crystalline structures of PVDF/SiC samples. Furthermore, the addition of SiC nanowire enhanced the transformation of non -polar a phase to polar phases and increased the relative fraction of 13 phase in PVDF. Due to the nucleating agent mechanism of SiC nanowires, the ion dipole interaction between the negatively charged surface of SiC nanowires and the positive CH2 groups in PVDF facilitated the formation of polar phases in PVDF.
Enhancement of Polar Phases in PVDF by Forming PVDF/SiC Nanowire Composite
(2016-12)
Huang, Jie-Fang
;
Han, Song-Jia
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Chen, Hui-Jiuan
;
Liu, Gui-Shi
;
Li, Gong-Tan
Different contents of silicon carbide (SiC) nanowires were mixed with Poly(vinylidene fluoride) (PVDF) to facilitate the polar phase crystallization. It was shown that the annealing temperature and SiC content affected on the phase and crystalline structures of PVDF/SiC samples. Furthermore, the addition of SiC nanowire enhanced the transformation of non -polar a phase to polar phases and increased the relative fraction of 13 phase in PVDF. Due to the nucleating agent mechanism of SiC nanowires, the ion dipole interaction between the negatively charged surface of SiC nanowires and the positive CH2 groups in PVDF facilitated the formation of polar phases in PVDF.
Enhancing Performance in Thin Tilm Transistors with Vacuum or Solution Processed Amorphous Oxide Semiconductors Towards Display Applications
(2018-01-01)
Chen, Changdong
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Li, Gongtan
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Li, MinMin
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Yang, Bo-Ru
;
Liu, Chuan
To simultaneously achieve high mobility and good reliability of thin-film transistors (TFTs), we controlled oxygen vacancies via nitrogen incorporation in InGaZnO TFTs from vacuum-or solution-based methods. For display applications, IGZO and crystalline silicon TFTs were integrated together to build hybrid CMOS. Also, additive patterning method is developed for solution-processed oxide semiconductors, based on which wafer-scale TFT arrays and NMOS have been demonstrated.
Fabrication of Embedded Silver Nanowires on Arbitrary Substrates with Enhanced Stability via Chemisorbed Alkanethiolate
(2017-05-03)
Liu, Gui-Shi
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Qiu, Jing-Shen
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Xu, Duo-Hua
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Zhou, Xianzhong
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Zhong, Dingyong
We propose a versatile yet practical transferring technique to fabricate a high performance and extremely stable silver nanowire (AgNW) transparent electrode on arbitrary substrates. Hydroxylated polyethylene glycol) terephthalate (PET) or poly(dimethylsiloxane) (PDMS) deposited with AgNWs was selectively decorated to lower its polar surface energy, so that the AgNWs were easily and efficiently transferred into an epoxy resin (EPR) as a freestanding film (AgNWs EPR) or onto various substrates. The AgNWs EPR capped with alkanethiolate monolayers exhibits high conductivity, low roughness, ultraflexibility, and strong corrosion resistance. Using the transferring process, AgNWs EPR was successfully constructed on rough, adhesive, flimsy, or complex curved substrates, including PET, thin optically clear adhesive, papers, a beaker, convex spherical PDMS, and leaves. A flexible touch panel enabling multitouch and a curved transparent heater on a beaker were first fabricated by using the composite film. These demonstrations suggest that the proposed technique for AgNWs is a promising strategy toward the next generation of flexible/portable/wearable electronics.
High contrast ratio emi-flective LCD with nano-particle transflector
(2007)
Yang, Bo-Ru
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Lin, Kun-Yueh
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Shieh, Han-Ping D.
;
Lee, Shih-Nan
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Chen, Chin H.
A novel emi-flective display that integrates a reflective liquid crystal display (R-LCD) and an organic light emitting diode (OLED) display was demonstrated. Under the light ambience (if 30 nits, the OLED achieved a gain factor of 8 in contrast ratio (CR) compared with the conventional non-integrated OLED: besides, the OLED was fully operational and the system's CR of 5000:1 at the viewing cone of 50 degrees could be achieved. Moreover, the R-LCD retained a CR of 10:1 at the viewing cone of 55 degrees in the bright ambience. To enhance the image quality of both R-LCD and OLED, we laid a nano-particle film (NPF) in the intermediate section of the hybrid device. The NPF was demonstrated to enhance the light extraction in transmission mode of the integrated device to 103% and the haze function of the reflection mode to a factor of 15 compared with the freestanding mirror.
High-brightness relaxed-bend state in a pi cell stabilized by synchronized polymerization
(2008-06-02)
Yang, Bo-Ru
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Elston, Steve J.
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Raynes, Peter
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Shieh, Han-Ping D.
;
光電工程學系
The authors report a synchronized polymer-stabilization technique which can be used to stabilize the nonpermanent states in liquid crystal devices. In this paper, a relaxed-bend state in a pi cell which has a lifetime of only 80 ms is observed and then stabilized by this proposed technique. After stabilizing, the pi cell is immune to undesirable recovery into the splay or twist states, and its optical contrast is much higher than that of the conventional polymer-stabilized pi cell. (C) 2008 American Institute of Physics.
Hybrid Effect of Crossed Alignment and Multi-Stacking Structure on the Percolation Behavior of Silver Nanowire Networks
(2015-07-01)
Yang, Bo-Ru
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Liu, Gui-Shi
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Han, Song-Jia
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Cao, Wu
;
Chen, Hui-Jiuan
Owing to the superiority of being flexible, highly conductive, and extremely transparent, silver nanowire (AgNW) has been regarded as a possible candidate to replace indium-tin-oxide (ITO) for flexible transparent conductive films (TCFs), flexible electronics, and flexible display applications. To make TCFs with lower sheet resistance (R-s), but without sacrificing the optical transmittance, the deployment of AgNWs is very critical. A crossed-alignment method along with multi-stacking structure was proposed to lower the percolative threshold, which thus can decrease the R-s by a factor of more than two, in the premise of not affecting the optical transmittance.
Integrating Poly-Silicon and InGaZnO Thin-Film Transistors for CMOS Inverters
(2017-09-01)
Chen, ChangDong
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Yang, Bo-Ru
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Liu, Chuan
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Zhou, Xing-Yu
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Hsu, Yuan-Jun
The applications of a-InGaZnO thin-film transistors (TFTs) to logic circuits have been limited owing to the intrinsic n-channel operation. In this paper, we demonstrated a hybrid inverter constructed by p-channel low-temperature poly-silicon (LTPS) TFTs and n-channel amorphous-indium-gallium-zinc-oxide (a-IGZO) TFTs. Hydrogenated LTPS TFTs and a-IGZO TFTs have been successfully fabricated on the same panel, followed by a rapid thermal annealing treatment to remove the hydrogens in the a-IGZO TFTs. The resulted hybrid inverter exhibits large noise margin closed to V-DD/2 and a high voltage gain as 68.3. Due to the complementary configurations in the static state, the inverter shows small current and thus consumes low power in hundreds of picowatts. As all the fabrication processes are compatible with conventional techniques, the reported results may open new opportunities in circuit design and applications for oxide TFTs.
Investigation of PVDF-TrFE composite with nanofillers for sensitivity improvement
(2016-07-01)
Chen, Hui-jiuan
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Han, Songjia
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Liu, Chuan
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Luo, Zhenhua
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Shieh, Han-Ping D.
Polyvinylidene fluoride-trifluoroethylene (PVDF-TrFE) is a good candidate for wearable tactile sensing application, owing to its flexibility and easy processing. In this paper, we studied the effect of mixing silver nano-fillers with different morphologies into PVDF-TrFE to improve the extent of beta phase crystallization and the piezoelectric performance. After blending, the piezoelectric responding voltage of the composite was increased by a factor of more than three. This improvement results from the PVDF-TrFE chain arranges differently onto the nano-fillers with different morphologies, thus affects the crystallization. (C) 2016 Elsevier B.V. All rights reserved.
Investigation of the transient symmetric H state in a pi cell
(2007-08-13)
Yang, Bo-Ru
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Elston, Steve J.
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Raynes, Peter
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Shieh, Han-Ping D.
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光電工程學系
The so-called symmetric H (H-s) state has been reported to have submillisecond response times, which results from the symmetric profile of the liquid crystal director; however, no direct evidence has been obtained to show the profile symmetry. The difficulty in proving this symmetric structure by direct observation results from the short lifetime of H-s state (typically around a few tens of milliseconds). In the work reported here, the authors utilize a burst driving method along with stroboscopic illumination from blue and red light emitting diodes to capture conoscopic images for the H-s director profile; these showed good agreement with their modeling. (c) 2007 American Institute of Physics.
Microchannel Wetting for Controllable Patterning and Alignment of Silver Nanowire with High Resolution
(2015-09-30)
Yang, Bo-Ru
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Cao, Wu
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Liu, Gui-Shi
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Chen, Hui-Jiuan
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Noh, Yong-Young
Patterning and alignment of conductive nanowires are essential for good electrical isolation and high conductivity in various applications. Herein a facile bottom-up, additive technique is developed to pattern and align silver nanowires (AgNWs) by manipulating wetting of dispersions in microchannels. By forming hydrophobic/hydrophilic micropatterns down to 8 mu m with fiuoropolymer (Cytop) and SiO2, the aqueous AgNW dispersions with the optimized surface tension and viscosity self-assemble into microdroplets and then dry to form anisotropic AgNW networks. The alignment degree characterized by the full width at half-maximum (FWHM) can be well-controlled from 39.8 degrees to 84.1 degrees by changing the width of microchannels. A mechanism is proposed and validated by statistical analysis on AgNW alignment, and a static model is proposed to guide the patterning of general NWs. The alignment reduced well the electrical resistivity of AgNW networks by a factor of 5 because of the formation of efficient percolation path for carrier conduction.
Modulation of Interface and Bulk States in Amorphous InGaZnO Thin-Film Transistors with Double Stacked Channel Layers
(2013-09-01)
Zhan, Runze
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Dong, Chengyuan
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Yang, Bo-Ru
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Shieh, Han-Ping D.
;
光電工程學系
A high-performance amorphous InGaZnO (a-IGZO) thin-film transistor (TFT) was achieved using a double stacked channel layer (DSCL). An oxygen-poor IGZO film was deposited in pure argon ambient as a buffer layer to prevent oxygen plasma bombardment and improve device performance. An oxygen-rich IGZO film was then deposited on top of that buffer layer to modulate device stability. With this structure, an interface with low oxygen-plasma-induced damage and few oxygen vacancies in the bulk was achieved using DSCL, leading to a higher stability of the threshold voltage. (C) 2013 The Japan Society of Applied Physics
Nitrogen-Doped Amorphous InZnSnO Thin Film Transistors With a Tandem Structure for High-Mobility and Reliable Operations
(2016-05)
Li, GongTan
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Yang, Bo-Ru
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Liu, Chuan
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Lee, Chia-Yu
;
Wu, Yuan-Chun
The threshold voltage shift (Delta V-th) in amorphous InZnSnO thin-film transistors (a-IZTO TFTs) during negative gate-bias stress (NGBS) is significantly improved by nitrogen doping. Numerous N-In bonds eliminate donorlike subgap states near the Fermi level, which improve stability during stress but degrade electron mobility. We developed tandem TFTs with an a-IZTO:N layer on top of an a-IZTO layer, in which mobility reaches 31.76 +/- 0.81 cm(2)/Vs and the reliability is improved. Especially, Delta V-th in NGBS is reduced by 80% for pristine a-IZTO devices. This simple but an effective method achieves fast and reliable operation in the a-IZTO TFTs.