• 제목/요약/키워드: Voltage holding ratio

검색결과 25건 처리시간 0.034초

Voltage Holding Ratio of a Homogeneously-Aligned Liquid-Crystal Cell

  • Lin, Yu-Ting;Lin, Yu-Jiun;Lee, Wei
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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    • pp.17-19
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    • 2009
  • The voltage and frequency dependence of voltage holding ratio (VHR) in a homogeneously-aligned liquid-crystal (LC) cell is studied in this paper. The discharge curves with different scan frequencies are obtained and the saturation phenomenon of VHR is observed under specific amplitudes of driving voltage. Our results suggest a reasonable concept to improve the VHR in LC displays without increasing the frame rate.

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Shorted anode p-i-n 스위칭 소자의 전기적 특성 (Electrical Characteristics of Shorted Anode P-I-N Switchs)

  • 이성재;민남기
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1994년도 하계학술대회 논문집 C
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    • pp.1469-1471
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    • 1994
  • This paper describes the structure and electrical characteristics of a shorted anode p-i-n switch. The device showed a significant improvement in the threshold voltage-to-holding voltage ratio, which is due to the suppression of the hole injection from the anode and to the gold gettering at the anode side. The shorted anode devices with a $100{\mu}m$ channel length have a threshold voltage of 300 volts and a holding voltage of 5.5 volts.

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IPS 셀의 전압보유율 및 잔류 DC 특성에 관한 연구 (A Study on the Voltage Holding Ratio and Residual DC Property in the IPS Cell)

  • 전용제;김향율;서대식;김재형;남상희
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 추계학술대회 논문집 전기물성,응용부문
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    • pp.174-177
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    • 2001
  • The voltage holding ratio (VHR) and Residual DC property in the in-plane switching (IPS) cell was studied Several IPS cells which have different concentrations of cynao liquid crystals (LCs) and different resistivities of fluorine LCs were fabricated VHR and residual DC voltage in the IPS cells using the capacitance-voltage (C-V) hysteresis method was measured. We found that the VHR of the IPS cell was decreasing with increasing concentration of cyano LC. The residual DC voltage of the IPS cell was decreasing with increasing concentration of cyano LCs. We suggest that the high polarity of cyano LC helps reducing the residual DC voltage.

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IPS셀의 전압보유율 및 잔류DC특성 연구 (A Study on VHR and Residual DC Property in the IPS Cells)

  • 김향율;서대식;남상희
    • 한국전기전자재료학회논문지
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    • 제15권2호
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    • pp.169-172
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    • 2002
  • The voltage holding ratio(VHR) and the residual DC property in the in-plane switching (IPS) cells on a polyimide surface was studied. Several IPS cells which have different concentrations of cyano liquid crystals (LCs) were fabricated. We found that the VHR of the IPS cell was decreased with increasing concentration of cyano LCs. Also, the VHR of the IPS cell was increased with increasing specific resistivity of fluorine LCs. The residual DC voltage of the IPS cell by capacitance-voltage (C-V) hysteresis method was decreased with increasing concentration of cyano LCs. The residual DC property of the IPS cell on the rubbed PI surface can be improved by high polarity of cyano LC.

그라핀 양자점을 도핑한 TN 셀의 고속 스위칭 특성 (Fast Switching Properties of TN Cell With Graphene Quantum Dots)

  • 김대현
    • 한국전기전자재료학회논문지
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    • 제27권2호
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    • pp.110-114
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    • 2014
  • In this study, we report the doping effect of graphene quantum dots (QDs) in nematic liquid crystal (NLC) system on rubbed polyimide (PI) surface. The good LC alignment and high thermal stability in QD-LC cell system on rubbed PI surfaces can be measured. Also, the low threshold voltage of QD-TN cell was observed about 2.77 V. The fast response time of 13.2 ms for QD-TN cell can be achieved. Finally, the good voltage holding ratio of QD-TN cell on rubbed PI surface was measured.

양극이 단락된 p-i-n 이중주입 스위칭 소자 (A shorted anode p-i-n double injection seitchning device)

  • 민남기;이성재;박하영
    • 전자공학회논문지A
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    • 제32A권7호
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    • pp.69-76
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    • 1995
  • A new device structure has been developed for p-i-n switches. In this structure, the phosphorus-diffused n$^{+}$ layter adjacent to the boron-doped anode is used to short the p$^{+}$ anode-channel(i-region). This change in the anode electrode structure results in a significant improvement in the threshold voltage-to-holding voltage($V_{Th}/V_{h}$) ratio, which is due to the suppression of the hold injection from the anode by the n$^{+}$ layer. The shorted anode p-i-n devices of a 100 .mu.m channel length show an extremely high threshold voltage in the 250~300 V range and a low holding voltage in the 5~9 V range. These features of the device are expected to acdelerate their practical application to power switching circuits.

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프리틸트각의 발생과 전기광학 특성에 있어서의 배향층의 효과 (Effect of alignment layer on pretilt angle generation and EO performance)

  • 박태규;서대식
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1999년도 추계학술대회 논문집
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    • pp.537-540
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    • 1999
  • Effect of alignment layers on pretilt angle generation and electrical characteristics in nematic liquid crystal(NLC) by using photo-alignment techniques on polyimide (PI) surface with side chain were studied. The generated pretilt angle of the NLC on rubbed PI surface with 1-layer is almost the same as that of the 2-layers. However, the generated pretilt angle of the NLC on photo-induced PI surface with 2-layers is larger than that of the 1-layer. Therefore, the pretilt angle of the NLC on photo-induced PI surface is attributed to surface roughness due to photo-depolymerization of the polymer with UV light irradiation on PI surface. Next we observed the same characteristics of voltage-transmittance (V-T) and response time for 1- and 2-layers on PI surface. We also observed the same voltage holding ratio (VHR) characteristics for 1- and 2-layers on photo-aligned PI surface. Consequently, we suggest that the VHR of photo-aligned TN-LCD is higher than that of the rubbing-aligned TN-LCD.

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경사진 자외선 조사를 이용한 TN-LCD의 전기광학 특성 (Electro-optical performance of TN-LCD wish oblique UV light irradiation on polyimide surface)

  • 서대식;박두석;한정민;황율연;박태규
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1998년도 춘계학술대회 논문집
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    • pp.113-116
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    • 1998
  • In this paper, we studied the electro-optical(EO) performance of photo-aligned twisted nematic(TN)-liquid crystal display(LCD) with oblique non-polarized ultraviolet(UV) light irradiation on polyimide(Pl) surface. We observed that the voltage-transmittance and response time characteristics of photo-aligned TN-LCD is almost same compared to conventional TN-LCD. Also, we observed that the voltage-holding-ratio(VHR) of photo-aligned TN-LCD is almost same compared to conventional TN-LCD.

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폴리이미드막에 편광되지 않은 UV광을 경사지게 조사한 광배향 TN-LCD의 전기광학특성에 관한 연구 (EO performance of photo-aligned TN-LCD with oblique non-polarized UV light irradiation on polymer surface)

  • 서대식;박태규;한정민;박두석;황율연
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 하계학술대회 논문집 D
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    • pp.1385-1387
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    • 1998
  • In this paper, we studied the electro-optical(EO) performance of photo-aligned twisted nematic(TN)-liquid crystal display(LCD) with oblique non-polarized ultraviolet (UV) light irradiation on polyimide (PI) surface. The monodomain alignment of photo-aligned TN-LCD is obtained with an angle of incidence of $85^{\circ}$ on PI surface. Also, we observed that the voltage transmittance and response time characteristics of photo-aligned TN-LCD is almost same compared to rubbing treated TN-LCD. Finally, we measured that the voltage-holding-ratio(VHR) of photo-aligned TN-LCD is almost same compared to rubbing treated TN-LCD.

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Study on Electrical Characteristics of Chloromethylated Polyimide

  • Yu, I.H.;Zhong, Z-X;Lee, M.H.;Lee, S.H.
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.I
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    • pp.472-475
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    • 2005
  • The electrical performances of liquid crystal (LC) cells with chloromethylated polyimide (CMPI) alignment layers were investigated. The CMPI layer was previously reported as a multifunctional layer that does role of LC alignment and planarization layer as well as photo-alignment material with high photosensitivity and excellent thermal stability. The capacitance-voltage (C-V) characteristics of LC cells with CMPI alignment layers were measured. Mechanical rubbing of the CMPI layer did not generate much difference in residual DC when compared to commercial PI. However, the LC cell with photo-oxidation CMPI layer shows a high residual DC value and a corresponding low voltage holding ratio (VHR) due to the photo-induced ionic charges on the alignment layer.

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