Low driving voltage by novel light scattering mechanism in polymer composite liquid crystal device

• Project/Area Number: 18K04257
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 21060:Electron device and electronic equipment-related
• Research Institution: Akita University
• Principal Investigator: Yamaguchi Rumiko 秋田大学, 理工学研究科, 教授 (30170799)
• Project Period (FY): 2018-04-01 – 2022-03-31
• Project Status: Completed (Fiscal Year 2021)
• Budget Amount: ¥4,290,000 (Direct Cost: ¥3,300,000、Indirect Cost: ¥990,000); Fiscal Year 2021: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000); Fiscal Year 2020: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000); Fiscal Year 2019: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000); Fiscal Year 2018: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000)
• Keywords: 高分子複合液晶 / 反応性メソゲン / 光散乱 / 低電圧駆動 / リバースモード / スマートウインドウ / レンズ効果 / 遠方光散乱パターン / 屈折率 / 駆動電圧 / 複合誘電率

Outline of Final Research Achievements

Driving voltage of a reverse mode liquid crystal devices in which an anisotropic polymer with a reactive mesogen group of about 3 to 10% is dispersed in the liquid crystal was successfully reduced without reducing the light scattering intensity. A "light scattering mechanism between the liquid crystal domains" was introduced in addition to the conventional "light scattering due to the difference in refractive index between the polymer and the liquid crystal". A simulation model incorporating a new light scattering mechanism was also constructed. Applied voltage of 5 V made it possible to electrically switch from the transparent state to the light scattering state in the liquid crystal devices.

Academic Significance and Societal Importance of the Research Achievements

大小の液晶ドメインの再配向電圧の違いに着目し，“液晶ドメイン間での光散乱機構”を導入することで，光散乱強度を損なうことなく，駆動電圧の低減に成功した。従来の“高分子―液晶間の屈折率差による光散乱”機構と比較し，新規な光散乱機構の導入は駆動電圧を約半分にまで低減できることを，数値解析的に明らかにすることができた。リバースモード液晶素子は，スマートウインドウとして期待されているが，光散乱状態をプロジェクタースクリーンとして用いることで，透明ディスプレイにも応用可能である。

Research Products

• [Journal Article] Electrical and Optical Model of Reverse Mode Liquid Crystal Cells with Low Driving Voltage (2021)
  • Author(s): R. Yamaguchi and K. Inoue
  • Journal Title: Journal of Photopolymer Science and Technology Volume: 34 Issue: 3 Pages: 315-320
  • DOI: 10.2494/photopolymer.34.315
  • NAID: 130008119695
  • ISSN: 0914-9244, 1349-6336
  • Year and Date: 2021-06-11
  • Peer Reviewed / Open Access
• [Journal Article] Improvement of Light Scattering in Reverse Mode Liquid Crystals using Micro-Lens Array Effect (2020)
  • Author(s): Yamaguchi Rumiko、Sagawa Kosuke、Yanase Satoshi
  • Journal Title: Journal of Photopolymer Science and Technology Volume: 33 Issue: 4 Pages: 369-372
  • DOI: 10.2494/photopolymer.33.369
  • NAID: 130007867656
  • ISSN: 0914-9244, 1349-6336
  • Year and Date: 2020-07-01
  • Peer Reviewed / Open Access
• [Journal Article] Thresholdless Electro-Optical Property in Quasi Homogeneous and Homeotropic Liquid Crystal Cells Using Weak Anchoring Surfaces (2019)
  • Author(s): YAMAGUCHI Rumiko
  • Journal Title: IEICE Transactions on Electronics Volume: E102.C Issue: 11 Pages: 810-812
  • DOI: 10.1587/transele.2019DIS0002
  • NAID: 130007740290
  • ISSN: 0916-8524, 1745-1353
  • Year and Date: 2019-11-01
  • Peer Reviewed
• [Journal Article] Louver Function in Hybrid Aligned Reverse Mode Using Dual Frequency Liquid Crystal (2019)
  • Author(s): Yamaguchi Rumiko、Ushizaki Ryo
  • Journal Title: Journal of Photopolymer Science and Technology Volume: 32 Issue: 4 Pages: 545-548
  • DOI: 10.2494/photopolymer.32.545
  • NAID: 130007744419
  • ISSN: 0914-9244, 1349-6336
  • Year and Date: 2019-06-24
  • Peer Reviewed / Open Access
• [Journal Article] Driving Voltage in Reverse Mode Cell Using Reactive Mesogen : Effect of UV Absorption of Liquid Crystal (2018)
  • Author(s): R. Yamaguchi, R. Sasaki and K. Inoue
  • Journal Title: Journal of Photopolymer Science and Technology Volume: 31 Issue: 3 Pages: 301-304
  • DOI: 10.2494/photopolymer.31.301
  • NAID: 130007481516
  • ISSN: 0914-9244, 1349-6336
  • Year and Date: 2018-06-25
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Presentation] Reverse mode smart window by UV irradiation through hole patterned photomask (2021)
  • Author(s): T. Ito and R. Yamaguchi
  • Organizer: The 19th Topical Meeting on the Optics of Liquid Crystals
  • Int'l Joint Research
• [Presentation] 等方性ポリマーと異方性ポリマーを混合したリバースモードPDLCの電気光学特性 (2021)
  • Author(s): 中川翔平，斎藤佑真，山口留美子
  • Organizer: 日本液晶学会 討論会
• [Presentation] ハイブリッド配向疑似TNモードにおける極角アンカリング力と弾性定数の関係 (2021)
  • Author(s): 山口 留美子，川田 竣也，麦沢 幸樹
  • Organizer: 電子情報通信学会2021 年総合大会
• [Presentation] Ultra-Low Driving Voltage in Quasi-Twisted Nematic Mode Using Weak / Strong Anchoring Hybrid Alignment Surface (2020)
  • Author(s): Rumiko Yamaguchi, Shunya Kawata
  • Organizer: THE 27TH INTERNATIONAL DISPLAY WORKSHOPS
  • Int'l Joint Research
• [Presentation] 凹レンズ効果を用いたリバースモード素子の開発に関する研究 (2020)
  • Author(s): 伊藤 耀希, 山口 留美子
  • Organizer: 電子情報通信学会2020 年ソサイエティ大会
• [Presentation] 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 (2020)
  • Author(s): 川田 竣也, 山口 留美子
  • Organizer: 第81回応用物理学会秋季学術講演会
• [Presentation] 凹レンズ効果によるリバースモード液晶素子の散乱特性向上に関する研究 (2020)
  • Author(s): 伊藤 耀希, 山口 留美子
  • Organizer: 非発光型ディスプレイ合同研究会
• [Presentation] 弱アンカリングハイブリッド配向による疑似TNモードの超低電圧駆動… (2020)
  • Author(s): 山口留美子
  • Organizer: 電子情報通信学会2020年総合大会
• [Presentation] Louver Function in Hybrid Aligned Reverse Mode Using Dual Frequency Liquid Crystal (2019)
  • Author(s): Rumiko Yamaguchi and Ryo Ushizaki
  • Organizer: The 36th International Conference of Photopolymer Science and Technology
  • Int'l Joint Research
• [Presentation] IMPROVEMENT OF REVERSE MODE LIQUID CRYSTALS USING LENS EFFECT (2019)
  • Author(s): Rumiko Yamaguchi, Kosuke Sagawa, Takuya Uchibori, Ryosuke Sasaki and Satoshi Yanase
  • Organizer: The 18th Topical Meeting on the Optics of Liquid Crystals
  • Int'l Joint Research / Invited
• [Presentation] Light Scattering of Ordinary Ray in Reverse Mode LC Cell Assisted by Micro Lens Effect (2019)
  • Author(s): Kosuke Sagawa, Rumiko Yamaguchi, Satoshi Yanase
  • Organizer: THE 26TH INTERNATIONAL DISPLAY WORKSHOPS
  • Int'l Joint Research
• [Presentation] Thresholdless and Ultra-Low Drive Voltage in Liquid Crystals with Weak Anchoring Boundaries (2019)
  • Author(s): Rumiko Yamaguchi
  • Organizer: Optics & Photonics Taiwan International Conference
  • Int'l Joint Research / Invited
• [Presentation] リバースモード液晶素子における屈折率ミスマッチングとレンズ効果を組み合わせた光散乱の相乗効果に関する研究 (2019)
  • Author(s): 佐川康介, 山口留美子, 梁瀬 智
  • Organizer: 2019年 日本液晶学会 討論会
• [Presentation] 2周波駆動液晶を用いたハイブリッド配向リバースモード液晶素子における重合時電圧印加の光散乱への影響 (2019)
  • Author(s): 牛崎 遼, 山口留美子
  • Organizer: 2019年 日本液晶学会 討論会
• [Presentation] 不均一UV照射によるツイステッドネマチック配向リバースモード液晶素子 (2019)
  • Author(s): 内堀拓哉, 佐々木亮輔, 山口留美子
  • Organizer: 2019年 日本液晶学会 討論会
• [Presentation] ツイステッドネマチックチック液晶素子における弱極角アンカリング効果 (2019)
  • Author(s): 山口留美子・坂本善紀
  • Organizer: 2019年電子情報通信学会総合大会
• [Presentation] 不均一UV照射リバースモード液晶素子の特性改善 (2019)
  • Author(s): 内堀卓也，佐々木 亮輔 山口留美子
  • Organizer: 電子情報通信学会技術研究報告 発光型/非発光型ディスプレイ合同研究会
• [Presentation] しきい電圧のないホモジニアスおよびホメオトロピック配向液晶素子 (2019)
  • Author(s): 山口留美子
  • Organizer: 電子情報通信学会技術研究報告 発光型/非発光型ディスプレイ合同研究会
• [Presentation] Thresholdless Electro-Optical Properties in Homogeneous and Homeotropic Liquid Crystal Cells (2018)
  • Author(s): R. Yamaguchi
  • Organizer: 25th International Display Workshops
  • Int'l Joint Research
• [Presentation] Effect of Critical Anchoring in Undistorted Twisted and Hybrid Aligned Liquid Crystal Cells (2018)
  • Author(s): R. Yamaguchi
  • Organizer: 9th Italian- Japanese Workshops on Liquid Crystals
  • Int'l Joint Research / Invited
• [Presentation] Hybrid Aligned Reverse Mode Cell Using Dual Frequency Liquid Crystal (2018)
  • Author(s): R. Ushizaki and R. Yamaguchi
  • Organizer: 27th International Liquid Crystal Conference
  • Int'l Joint Research
• [Presentation] Improvement of Light Scattering in Reverse mode Liquid Crystal Cell with Microlens Structure (2018)
  • Author(s): K. Sagawa and R. Yamaguchi
  • Organizer: 27th International Liquid Crystal Conference
  • Int'l Joint Research
• [Presentation] Polymer Stabilized Reverse Mode Liquid Crystal Cell by UV Irradiation through Photomasks (2018)
  • Author(s): R. Sasaki and R. Yamaguchi
  • Organizer: 27th International Liquid Crystal Conference
  • Int'l Joint Research
• [Presentation] Numerical Analysis of Electro-Optical Property in Twisted Nematic Cell Using Strong/Weak Anchoring (2018)
  • Author(s): Y. Sakamoto and R. Yamaguchi
  • Organizer: 27th International Liquid Crystal Conference
  • Int'l Joint Research
• [Presentation] Twist Angle Controllable Liquid Crystal Cell by Out-of-Plane Filed Using Strong/Weak Anchoring surfaces (2018)
  • Author(s): R. Yamaguchi and Y. Sakamoto
  • Organizer: 27th International Liquid Crystal Conference
  • Int'l Joint Research / Invited
• [Presentation] Anchoring control by nematic liquid crystal mixture on rubbed Poly (4-vinylpyridine) surface (2018)
  • Author(s): R. Yamaguchi
  • Organizer: 27th International Liquid Crystal Conference
  • Int'l Joint Research
• [Presentation] Nonlinear Optical Property of Negative Type Nematic Liquid Crystal Assisted by Voltage Application : Numerical Analysis (2018)
  • Author(s): R. Yamaguchi
  • Organizer: 27th International Liquid Crystal Conference
  • Int'l Joint Research
• [Presentation] しきい値電圧を持たないホモジニアス及びホメオトロピック配向液晶素子 (2018)
  • Author(s): 山口留美子
  • Organizer: 2018年 日本液晶学会 討論会