YAMAGUCHI Rumiko

写真a

Affiliation

Graduate School of Engineering Science  Cooperative Major in Life Cycle Design Engineering 

Research Fields, Keywords

Optoelecrtronics, Liquid crystal devices

Graduating School 【 display / non-display

  • 1980.04
    -
    1984.03

    Akita University     Graduated

Campus Career 【 display / non-display

  • 2019.04
    -
    Now

    Akita University   Graduate School of Engineering Science   Cooperative Major in Life Cycle Design Engineering   Professor  

  • 2005.12
    -
    2019.03

    Akita University   Graduate School of Engineering Science,   Associate Professor  

Academic Society Affiliations 【 display / non-display

  • 2012.04
    -
    Now
     

    UNITED STATES

     

    the Society for Information DIsplay

Research Field (grants-in-aid-for-scientific-research classification) 【 display / non-display

  • Optical engineering, Photon science

  • Electronic materials/Electric materials

  • Electron device/Electronic equipment

 

Thesis for a degree 【 display / non-display

  • 高分子・ネマティック液晶界面における配向現象とその応用に関する研究

    山口留美子 

      2002.04

    Single author

Published Papers 【 display / non-display

  • Ultra-Low Driving Voltage in Quasi-Twisted Nematic Mode Using Weak / Strong Anchoring Hybrid Alignment Surface

    Rumiko Yamaguchi, Shunya Kawata

    Proceedings of the International Display Workshops   27   131 - 132   2020.12  [Refereed]

    Domestic Co-author

    A hybrid twisted nematic cell was designed using strong and weak polar anchoring surfaces. The LC director distribution without the voltage was the same as a conventional 90° TN. Electro-optical properties were numerically analyzed and a driving voltage of less than 1/5 of the TN cell was obtained.

  • Improvement of light scattering in reverse mode liquid crystals using micro-lens array effect

    Yamaguchi R., Sagawa K., Yanase S.

    Journal of Photopolymer Science and Technology ( Journal of Photopolymer Science and Technology )  33 ( 4 ) 369 - 372   2020.04  [Refereed]

    Domestic Co-author

    <p>A reverse mode liquid crystal (LC) characteristic which shows a transparent voltage off-state and a light scattering on-state can be obtained by two light scattering mechanisms. One is using an index mismatching between LC and polymer matrix and another is using a micro-lens array with a short focal length. Here, we combine two reverse mode technologies in one LC cell. We investigate relations between the cell thickness and the lens diameter of a hole array patterned electrode and successfully obtained the stronger light scattering with low driving voltage. Not only an extraordinary ray but an ordinary ray can also be scattered by non-uniform electric field which is caused by using hole pattered electrodes on both side of the substrates.</p>

    DOI CiNii

  • Thresholdless and Ultra-Low Drive Voltage in Liquid Crystals with Weak Anchoring Boundaries

    Rumiko Yamaguchi

    Optics & Photonics Taiwan International Conference     2019.12

    Single author

  • Thresholdless electro-optical property in quasi homogeneous and homeotropic liquid crystal cells using weak anchoring surfaces

    Rumiko YAMAGUCHI

    IEICE TRANS. ELECTRON ( The Institute of Electronics, Information and Communication Engineers )  E102-C ( 11 ) 810 - 812   2019.11  [Refereed]

    Single author

    Liquid crystal director distributions between strong and weak polar anchoring surfaces in hybrid aligned cells are numerically analyzed. When the anchoring is a critical one, homogeneously or homeotropicly liquid crystal alignment can be obtained. Such cells have no threshold voltage and a driving voltage can be reduced less than 0.5 volt. © 2019 The Institute of Electronics, Information and Communication Engineers.

    DOI

  • Light Scattering of Ordinary Ray in Reverse Mode LC Cell Assisted by Micro Lens Effect

    Kosuke Sagawa, Rumiko Yamaguchi, Satoshi Yanase

    THE 26TH INTERNATIONAL DISPLAY WORKSHOPS   26   368 - 369   2019.11  [Refereed]

    Domestic Co-author

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Review Papers 【 display / non-display

  • Effect of Absorption Anisotropy in the UV Region on the Shutter Properties of Twisted Nematic Liquid Crystal Devices

      120 ( 345 ) 1 - 4   2021.01

    Summary of the papers read (national conference and other science council)   Domestic Co-author

    A reverse mode LC cell which is clear in a voltage-off state and a light scattering state under the voltage application has been proposed. Some mechanisms of the light scattering have been reported, one is by a microlens array system and another is a refractive index mismatching between a polymer matrix and liquid crystal domains. In this study, we have investigated the reverse mode LC cell by using both of the microlens array and the polymer dispersion light scattering mechanisms. An n-type LC was used and a hole patterned electrode was prepared to make a concave microlens array. Electro-optical properties have been measured in LC cells using the lens effect, a polymer matrix type and the combination of two light scattering mechanism. A contribution of each light scattering mechanism has been discussed and light scattering properties was improved when the cell thickness is optimized in the combination cell.

  • Light scattering of reverse mode liquid crystal improved by concave microlens array

      120 ( 345 ) 5 - 8   2021.01

    Summary of the papers read (national conference and other science council)   Domestic Co-author

    A reverse mode LC cell which is clear in a voltage-off state and a light scattering state under the voltage application has been proposed. Some mechanisms of the light scattering have been reported, one is by a microlens array system and another is a refractive index mismatching between a polymer matrix and liquid crystal domains. In this study, we have investigated the reverse mode LC cell by using both of the microlens array and the polymer dispersion light scattering mechanisms. An n-type LC was used and a hole patterned electrode was prepared to make a concave microlens array. Electro-optical properties have been measured in LC cells using the lens effect, a polymer matrix type and the combination of two light scattering mechanism. A contribution of each light scattering mechanism has been discussed and light scattering properties was improved when the cell thickness is optimized in the combination cell.

  • Thresholdless Electro-Optical Property in Homogeneously and Homeotropically Alignment Liquid Crystal Cells -Potential for Ultra Low Driving Voltage-

      23 ( 234 ) 182 - 187   2019.09

    Introduction and explanation (scientific journal)   Domestic Co-author

    CiNii

  • Twisted nematic Reverse mode liquid crystal cell with nonuniform UV irradiation

    Uchibori Takuya, Sasaki Ryousuke, Yamaguchi Rumiko

    Proceedings of Japanese Liquid Crystal Society Annual meeting ( THE JAPANESE LIQUID CRYSTAL SOCIETY )  2019 ( 0 ) PA45 - PA45   2019.09

    Summary of the papers read (national conference and other science council)   Domestic Co-author

    <p>A reverse mode liquid crystal cell containing photoreactive mesogen scatters incident light when a voltage is applied. In this study, A 90° TN cell was prepared. A two-step irradiation with UV light was performed, a first irradiation through a photomask and a second irradiation without the mask. Electro-optical properties were measured and the threshold voltage was successfully reduced by non-uniform UV irradiation. Moreover, polarization microscope observation were performed and the light scattering state which attributed to the 1st UV irradiation condition was clarified. The scattering state with nonuniform UV irradiation was also affected by liquid crystal materials. </p>

    DOI CiNii

  • Syergistic effect of Index mismatching and Lens properties on Lignt scattering in Reverse mode Liquid Crystal

    Sagawa Kosuke, Yamaguchi Rumiko, Yanase Satoshi

    Proceedings of Japanese Liquid Crystal Society Annual meeting ( THE JAPANESE LIQUID CRYSTAL SOCIETY )  2019 ( 0 ) 1C04   2019.09

    Summary of the papers read (national conference and other science council)   Domestic Co-author

    <p>We have investigated a reverse mode LC cell which has a transparent off-state and light scattering on-state. We propose the reverse mode LC cell prepared by combining the polymer composite and microlens array systems to improve light scattering property. Electrooptical properties, POM images and light scattering pattern have been investigated in three types of reverse mode cells with index mismatching effect, microlens effect and combination of them. </p>

    DOI CiNii

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Grant-in-Aid for Scientific Research 【 display / non-display

  • Grant-in-Aid for Scientific Research(C)

    Project Year: 2018.04  -  Now 

  • Grant-in-Aid for Scientific Research(C)

    Project Year: 2015.04  -  2018.03 

  • Grant-in-Aid for Scientific Research(C)

    Project Year: 2012.04  -  2015.03 

  • Grant-in-Aid for Scientific Research(C)

    Project Year: 2009.04  -  2012.03 

  • Grant-in-Aid for Scientific Research(C)

    Project Year: 2007.04  -  2009.03 

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Presentations 【 display / non-display

  • Ultra-Low Driving Voltage in Quasi-Twisted Nematic Mode Using Weak / Strong Anchoring Hybrid Alignment Surface

    Rumiko Yamaguchi and Shunya Kawata

    International Display Workshops  2020.12  -  2020.12 

  • ハイブリッド配向素子における疑似TNモードの超低電 圧駆動スイッチング特性

    川田 竣也, 山口 留美子

    第81回応用物理学会秋季学術講演会  (オンライン開催)  2020.09  -  2020.09  応用物理学会

  • Thresholdless and Ultra-Low Drive Voltage in Liquid Crystals with Weak Anchoring Boundaries

    Rumiko Yamaguchi  [Invited]

    Optics & Photonics Taiwan International Conference   2019.12  -  2019.12 

  • Light Scattering of Ordinary Ray in Reverse Mode LC Cell Assisted by Micro Lens Effect

    Kosuke Sagawa , Rumiko Yamaguchi , Satoshi Yanase

    THE 26TH INTERNATIONAL DISPLAY WORKSHOPS  2019.11  -  2019.11 

  • IMPROVEMENT OF REVERSE MODE LIQUID CRYSTALS USING LENS EFFECTS

    R. Yamaguchi , K. Sagawa , T. Uchibori, R. Sasaki and S. Yanase  [Invited]

    Topical Meeting on the Optics of Liquid Crystals   2019.09  -  2019.09 

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Academic Activity 【 display / non-display

  • 2015.04
     
     

    the Society for Information DIsplay