Details

<p>Series Editor’s Foreword xv</p> <p>List of Contributors xvii</p> <p><b>1 Introduction 1<br /> </b><i>Darran R. Cairns, Gregory P. Crawford, and Dirk J. Broer</i></p> <p>1.1 Toward Flexible Mobile Devices 1</p> <p>1.2 Flexible Display Layers 2</p> <p>1.3 Other Flexible Displays and Manufacturing 2</p> <p><b>2 Engineered Films for Display Technology 5<br /> </b><i>W.A. MacDonald</i></p> <p>2.1 Introduction 5</p> <p>2.2 Factors Influencing Film Choice 5</p> <p>2.2.1 Application Area 5</p> <p>2.2.2 Physical Form/Manufacturing Process 6</p> <p>2.2.3 Film Property Set 7</p> <p>2.2.3.1 Polymer Type 7</p> <p>2.2.3.2 Optical Clarity 9</p> <p>2.2.3.3 Birefringence 10</p> <p>2.2.3.4 The Effect of Thermal Stress on Dimensional Reproducibility 10</p> <p>2.2.3.5 Low-bloom Films 11</p> <p>2.2.3.6 Solvent and Moisture Resistance 12</p> <p>2.2.3.7 The Effect of Mechanical Stress on Dimensional Reproducibility 16</p> <p>2.2.3.8 Surface Quality 18</p> <p>2.3 Summary of Key Properties of Base Substrates 19</p> <p>2.4 Planarizing Coatings 21</p> <p>2.5 Examples of Film in Use 23</p> <p>2.6 Concluding Remarks 24</p> <p>Acknowledgments 25</p> <p><b>3 Liquid Crystal Optical Coatings for Flexible Displays 27<br /> </b><i>Owain Parri, Johan Lub, and Dirk J. Broer</i></p> <p>3.1 Introduction 27</p> <p>3.2 LCN Technology 27</p> <p>3.3 Thin-film Polarizers 29</p> <p>3.3.1 Smectic Polarizers 29</p> <p>3.3.2 Cholesteric Polarizers 32</p> <p>3.4 Thin-film Retarders 34</p> <p>3.4.1 Reactive Mesogen Retarders 35</p> <p>3.4.2 Chromonic Liquid Crystal-based Retarders 37</p> <p>3.4.3 Liquid Crystal Alignment and Patterned Retarders 37</p> <p>3.5 Color Filters 41</p> <p>3.6 Conclusion 43</p> <p><b>4 Large Area Flexible Organic Field-effect Transistor Fabrication 47<br /> </b><i>Zachary A. Lamport, Marco Roberto Cavallari, and Ioannis Kymissis</i></p> <p>4.1 Introduction 47</p> <p>4.2 Substrates 48</p> <p>4.3 Photolithography 49</p> <p>4.4 Printing for Roll-to-roll Fabrication 52</p> <p>4.4.1 Inkjet Printing 52</p> <p>4.4.2 Gravure and Flexographic Printing 55</p> <p>4.4.3 Screen Printing 56</p> <p>4.4.4 Aerosol Jet Printing 56</p> <p>4.4.5 Contact Printing 58</p> <p>4.4.6 Meniscus Dragging 60</p> <p>4.5 Conclusions 62</p> <p><b>5 Metallic Nanowires, Promising Building Nanoblocks for Flexible Transparent Electrodes 67<br /> </b><i>Jean-Pierre Simonato</i></p> <p>5.1 Introduction 67</p> <p>5.2 TEs Based on Metallic Nanowires 68</p> <p>5.2.1 Metallic Nanowires, New Building Nanoblocks 68</p> <p>5.2.2 Random Network Fabrication 69</p> <p>5.2.3 Optical Characterization 70</p> <p>5.2.4 Electrical Characterization 71</p> <p>5.2.5 Mechanical Aspect 73</p> <p>5.3 Application to Flexible Displays 73</p> <p>5.3.1 Touch Screens 73</p> <p>5.3.2 Light-emitting Diodes Displays 74</p> <p>5.3.3 Electrochromic Flexible Displays 76</p> <p>5.3.4 Other Displays 77</p> <p>5.4 Conclusions 78</p> <p><b>6 Optically Clear Adhesives for Display Assembly 85<br /> </b><i>Albert I. Everaerts</i></p> <p>6.1 Introduction 85</p> <p>6.2 OCA Definition and General Performance Specifications 86</p> <p>6.3 Application Examples and Challenges 89</p> <p>6.3.1 Outgassing Tolerant Adhesives 90</p> <p>6.3.2 Anti-whitening Adhesives 91</p> <p>6.3.3 Non-corrosive OCAs 92</p> <p>6.3.4 Compliant OCAs for High Ink-step Coverage and Mura-free Assembly of LCD Panels 94</p> <p>6.3.5 Reworkable OCAs 102</p> <p>6.3.6 Barrier Adhesives 103</p> <p>6.4 Summary and Remaining Challenges 104</p> <p><b>7 Self-healing Polymer Substrates 107<br /> </b><i>Progyateg Chakma, Zachary A. Digby, and Dominik Konkolewicz</i></p> <p>7.1 Introduction 107</p> <p>7.2 General Classes of Self-healing Polymers 108</p> <p>7.2.1 Types of Dynamic Bonds in Self-healing Polymers 109</p> <p>7.2.2 Supramolecularly Crosslinked Self-healing Polymers 109</p> <p>7.2.2.1 Hydrogen Bonding 110</p> <p>7.2.2.2 π–π Stacking 110</p> <p>7.2.2.3 Ionic Interactions 111</p> <p>7.2.3 Dynamic-covalently Crosslinked Self-healing Polymers 111</p> <p>7.2.3.1 Cycloaddition Reactions 111</p> <p>7.2.3.2 Disulfides-based Reversible Reactions 112</p> <p>7.2.3.3 Acylhydrazones 113</p> <p>7.2.3.4 Boronate Esters 113</p> <p>7.3 Special Considerations for Flexible Self-healing Polymers 114</p> <p>7.4 Incorporation of Electrically Conductive Components 115</p> <p>7.4.1 Metallic Conductors 115</p> <p>7.4.2 Conductive Polymers 116</p> <p>7.4.3 Carbon Materials 118</p> <p>7.4.4 Polymerized Ionic Liquids 119</p> <p>7.5 Additional Possibilities Enabled by Three-dimensional Printing 119</p> <p>7.6 Concluding Remarks 121</p> <p><b>8 Flexible Glass Substrates 129<br /> </b><i>Armin Plichta, Andreas Habeck, Silke Knoche, Anke Kruse, Andreas Weber, and Norbert Hildebrand</i></p> <p>8.1 Introduction 129</p> <p>8.2 Display Glass Properties 129</p> <p>8.2.1 Overview of Display Glass Types 129</p> <p>8.2.2 Glass Properties 130</p> <p>8.2.2.1 Optical Properties 130</p> <p>8.2.2.2 Chemical Properties 130</p> <p>8.2.2.3 Thermal Properties 131</p> <p>8.2.2.4 Surface Properties 132</p> <p>8.2.2.5 Permeability 133</p> <p>8.3 Manufacturing of Thin “Flexible’’ Glass 134</p> <p>8.3.1 Float and Downdraw Technology for Special Glass 134</p> <p>8.3.2 Limits 135</p> <p>8.3.2.1 Thickness Limits for Production 135</p> <p>8.3.2.2 Surface Quality Limits for Production 136</p> <p>8.4 Mechanical Properties 137</p> <p>8.4.1 Thin Glass and Glass/Plastic Substrates 137</p> <p>8.4.2 Mechanical Test Methods for Flexible Glasses 137</p> <p>8.5 Improvement in Mechanical Properties of Glass 140</p> <p>8.5.1 Reinforcement of Glass Substrates 140</p> <p>8.5.1.1 Principal Methods of Reinforcement 141</p> <p>8.5.1.2 Materials for Reinforcement Coatings 141</p> <p>8.6 Processing of Flexible Glass 142</p> <p>8.6.1 Cleaning 143</p> <p>8.6.2 Separation 143</p> <p>8.7 Current Thin Glass Substrate Applications and Trends 144</p> <p>8.7.1 Displays 145</p> <p>8.7.2 Touch Panels 145</p> <p>8.7.3 Sensors 145</p> <p>8.7.4 Wafer-level Chip Size Packaging 146</p> <p><b>9 Toward a Foldable Organic Light-emitting Diode Display 149<br /> </b><i>Meng-Ting Lee, Chi-Shun Chan, Yi-Hong Chen, Chun-Yu Lin, Annie Tzuyu Huang, Jonathan HT Tao, and Chih-Hung Wu</i></p> <p>9.1 Panel Stack-up Comparison: Glass-based and Plastic-based Organic Light-emitting Diode 149</p> <p>9.1.1 Technology for Improving Contrast Ratio of OLED Display 151</p> <p>9.2 CF–OLED for Achieving Foldable OLED Display 153</p> <p>9.2.1 Mechanism of the AR coating in CF–OLED 154</p> <p>9.2.2 Optical Performance of CF–OLED 155</p> <p>9.3 Mechanical Performance of CF–OLED 157</p> <p>9.3.1 Bi-directional Folding Performance and Minimum Folding Radius of SPS Cf–oled 159</p> <p>9.4 Touch Panel Technology of CF–OLED 160</p> <p>9.5 Foldable Application 162</p> <p>9.5.1 Foldable Technology Summary 162</p> <p>9.5.1.1 Polymer Substrates and Related Debonding Technology 162</p> <p>9.5.1.2 Alternative TFT Types to LTPS 162</p> <p>9.5.1.3 Encapsulation Systems to Protect Devices against Moisture 163</p> <p>9.5.2 Novel and Next-generation Display Technologies 163</p> <p><b>10 Flexible Reflective Display Based on Cholesteric Liquid Crystals 167<br /> </b><i>Deng-Ke Yang, J. W. Shiu, M. H. Yang, and Janglin Che</i></p> <p>10.1 Introduction to Cholesteric Liquid Crystal 167</p> <p>10.2 Reflection of CLC 169</p> <p>10.3 Bistable CLC Reflective Display 171</p> <p>10.4 Color Design of Reflective Bistable CLC Display 173</p> <p>10.4.1 Mono-color Display 173</p> <p>10.4.2 Full-color Display 173</p> <p>10.5 Transitions between Cholesteric States 175</p> <p>10.5.1 Transition from Planar State to Focal Conic State 175</p> <p>10.5.2 Transition from Focal Conic State to Homeotropic State 177</p> <p>10.5.3 Transition from Homotropic State to Focal Conic State 177</p> <p>10.5.4 Transition from Homeotropic State to Transient Planar State 178</p> <p>10.5.5 Transition from Transient Planar State to Planar State 179</p> <p>10.6 Driving Schemes 181</p> <p>10.6.1 Response to Voltage Pulse 181</p> <p>10.6.2 Conventional Driving Scheme 183</p> <p>10.6.3 Dynamic Driving Scheme 183</p> <p>10.6.4 Thermal Driving Scheme 185</p> <p>10.6.5 Flow Driving Scheme 186</p> <p>10.7 Flexible Bistable CLC Reflective Display 187</p> <p>10.8 Bistable Encapsulated CLC Reflective Display 188</p> <p>10.9 Production of Flexible CLC Reflective Displays 189</p> <p>10.9.1 Color e-Book with Single-layered Structure 191</p> <p>10.9.2 Roll-to Roll E-paper and Applications 195</p> <p>10.10 Conclusion 202</p> <p><b>11 Electronic Paper 207<br /> </b><i>Guofu Zhou, Alex Henzen, and Dong Yuan</i></p> <p>11.1 Introduction 207</p> <p>11.2 Electrophoretic Display 210</p> <p>11.2.1 Development History and Working Principle 210</p> <p>11.2.2 Materials 212</p> <p>11.2.2.1 Colored Particles/Pigments 212</p> <p>11.2.2.2 Capsule Shell Materials 213</p> <p>11.2.2.3 Suspending Medium (Mobile Phase) 213</p> <p>11.2.2.4 Charge Control Agents 213</p> <p>11.2.2.5 Stabilizers 213</p> <p>11.2.3 Device Fabrication 214</p> <p>11.2.4 Flexible EPD 215</p> <p>11.3 Electrowetting Displays 216</p> <p>11.3.1 Development History and Working Principle 216</p> <p>11.3.2 Materials 218</p> <p>11.3.2.1 Absorbing (Dyed) Hydrophobic Liquid 218</p> <p>11.3.3 Device Fabrication 220</p> <p>11.3.4 Flexible EWD 221</p> <p>11.4 Other E-paper Display Technologies and Feasibility of Flexibility 222</p> <p>11.4.1 Pcd 222</p> <p>11.4.2 Lpd 223</p> <p>11.5 Cholesteric (Chiral Nematic) LCDs 224</p> <p>11.6 Electrochromic Displays 224</p> <p>11.7 MEMS Displays 226</p> <p><b>12 Encapsulation of Flexible Displays: Background, Status, and Perspective 229<br /> </b><i>Lorenza Moro and Robert Jan Visser</i></p> <p>12.1 Introduction 229</p> <p>12.2 Background 230</p> <p>12.3 Multilayer TFE Technology 234</p> <p>12.3.1 Multilayer Approach 234</p> <p>12.3.2 Inorganic Layer Deposition Techniques 237</p> <p>12.3.3 Organic Layer Deposition Techniques 238</p> <p>12.4 Current Technology Implementation 242</p> <p>12.5 Future Developments 246</p> <p>12.6 Conclusions 249</p> <p>Acknowledgments 250</p> <p><b>13 Flexible Battery Fundamentals 255<br /> </b><i>Nicholas Winch, Darran R. Cairns, and Konstantinos A. Sierros</i></p> <p>13.1 Introduction 255</p> <p>13.2 Structural and Materials Aspects 256</p> <p>13.2.1 Shape 257</p> <p>13.2.2 One-dimensional Batteries 257</p> <p>13.2.3 Two-dimensional Planar Batteries 258</p> <p>13.2.4 Solid versus Liquid Electrolyte 259</p> <p>13.2.5 Carbon Additives 259</p> <p>13.3 Examples of Flexible Batteries 260</p> <p>13.4 Future Perspectives 266</p> <p><b>14 Flexible and Large-area X-ray Detectors 271<br /> </b><i>Gerwin Gelinck</i></p> <p>14.1 Introduction 271</p> <p>14.2 Direct and Indirect Detectors 272</p> <p>14.3 Thin-film Photodiode Sensors for Indirect-conversion Detectors 273</p> <p>14.3.1 Performance Parameters 273</p> <p>14.3.2 Photodiode Materials on Plastic Substrates 275</p> <p>14.3.2.1 Amorphous Silicon 275</p> <p>14.3.2.2 Organic Semiconductor Materials 275</p> <p>14.4 TFT Array 277</p> <p>14.4.1 Pixel Architecture and Transistor Requirements 277</p> <p>14.4.2 Flexible Transistor Arrays 278</p> <p>14.5 Medical-grade Detector 282</p> <p>14.6 Summary and Outlook 283</p> <p><b>15 Interacting with Flexible Displays 287<br /> </b><i>Darran R. Cairns and Anthony S. Weiss</i></p> <p>15.1 Introduction 287</p> <p>15.2 Touch Technologies in Non-Flexible Displays 287</p> <p>15.2.1 Resistive Touch Sensors 287</p> <p>15.2.2 4-Wire Resistive 288</p> <p>15.2.3 5-Wire Resistive 289</p> <p>15.2.4 Capacitive Sensing 290</p> <p>15.2.5 Surface Capacitive 291</p> <p>15.2.6 Projected Capacitive 291</p> <p>15.2.7 Infrared Sensing 293</p> <p>15.2.8 Surface Acoustic Wave 293</p> <p>15.2.9 Bending Wave Technologies 294</p> <p>15.3 Touch Technologies in Flexible Displays 294</p> <p>15.4 Summary 299</p> <p><b>16 Mechanical Durability of Inorganic Films on Flexible Substrates 301<br /> </b><i>Yves Leterrier</i></p> <p>16.1 Introduction 301</p> <p>16.2 Flexible Display Materials 302</p> <p>16.2.1 Property Contrast between Coating and Substrate Materials 302</p> <p>16.2.2 Determination of Mechanical Properties of Inorganic Coatings 302</p> <p>16.3 Stress and Strain Analyses 304</p> <p>16.3.1 Intrinsic, Thermal, and Hygroscopic Stresses and Strains 304</p> <p>16.3.2 Strain Analysis of Multilayer Films under Bending 307</p> <p>16.3.3 Critical Radius of Curvature 308</p> <p>16.4 Failure Mechanics of Brittle Films 309</p> <p>16.4.1 Damage Phenomenology under Tensile and Compressive Loading 309</p> <p>16.4.2 Experimental Methods 310</p> <p>16.4.3 Fracture Mechanics Analysis 311</p> <p>16.4.4 Role of Internal Stresses 312</p> <p>16.4.5 Influence of Film Thickness on Critical Strain 312</p> <p>16.5 Durability Influences 313</p> <p>16.5.1 Influence of Temperature 313</p> <p>16.5.2 Fatigue 314</p> <p>16.5.3 Corrosion 315</p> <p>16.6 Toward Robust Layers 317</p> <p>16.7 Final Remarks 317</p> <p>Acknowledgments 318</p> <p>Nomenclature 318</p> <p><b>17 Roll-to-roll Production Challenges for Large-area Printed Electronics 325<br /> </b><i>Dr. Grzegorz Andrzej Potoczny</i></p> <p>17.1 Introduction 325</p> <p>17.2 Infrastructure 327</p> <p>17.3 Equipment 328</p> <p>17.4 Materials 329</p> <p>17.5 Processing 331</p> <p>17.6 Summary 334</p> <p><b>18 Direct Ink Writing of Touch Sensors and Displays: Current Developments and Future Perspectives 337<br /> </b><i>Konstantinos A. Sierros and Darran R. Cairns</i></p> <p>18.1 Introduction 337</p> <p>18.2 DIW and Ink Development 338</p> <p>18.3 Applications of DIW for Displays and Touch Sensors 343</p> <p>18.4 Future Challenges and Opportunities 347</p> <p><b>19 Flexible Displays for Medical Applications 351<br /> </b><i>Uwadiae Obahiagbon, Karen S. Anderson, and Jennifer M. Blain Christen</i></p> <p>19.1 Introduction 351</p> <p>19.1.1 Flexible Displays in Medicine 351</p> <p>19.1.2 A Brief Historical Perspective 351</p> <p>19.1.3 Application of Flexible Displays for Biochemical Analysis 352</p> <p>19.1.4 OLEDs and Organic Photodiodes as Optical Excitation Sources and Detectors 352</p> <p>19.1.5 Device Integration 354</p> <p>19.1.6 Fluorescence, Photoluminescence Intensity, and Decay-time Sensing 355</p> <p>19.2 Flexible OLEDs for Oxygen Sensors 356</p> <p>19.3 Glucose Sensing Using Flexible Display Technology 358</p> <p>19.4 POC Disease Diagnosis and Pathogen Detection Using Flexible Display Optoelectronics 359</p> <p>19.5 Flexible Display Technology for Multi-analyte Sensor Array Platforms 364</p> <p>19.5.1 Integrated LOC and Flexible Display Devices 364</p> <p>19.5.2 Multiplexed Sensor Platforms 364</p> <p>19.6 Medical Diagnostic Displays 366</p> <p>19.7 Wearable Health Monitoring Devices Based on Flexible Displays 366</p> <p>19.7.1 Monitoring Vital Signs Using Flexible Display Technology 367</p> <p>19.7.2 Flexible Display Technology for Phototherapy 369</p> <p>19.7.3 Smart Clothing Using Flexible Display Technology 370</p> <p>19.8 Competing Technologies, Challenges, and Future Trends 371</p> <p>19.9 Conclusion 372</p> <p>Acknowledgment 373</p> <p>Conflicts of Interest 373</p> <p>Index 379</p>

<p><b>Darran R. Cairns, PhD, </b>is a member of the Faculty in the School of Science & Engineering at University of Missouri - Kansas City, USA. His research interests include solution-based processing of composite materials including sol-gel materials, nano-composite materials, and liquid crystalline materials and composites. <p><b>Dirk J. Broer, </b>is a Polymer Chemist specialized in polymer structuring and self-organizing polymer networks. This entails the development of polymers with new functionalities and integrating them into devices to meet industrial and societal challenges in the fields of sustainable energy, water-management, healthcare and personal comfort. <p><b>Gregory P. Crawford, PhD, </b>is President of Miami University, USA, and Professor of Physics. His research interests include liquid crystal and polymer materials for display and biotechnology applications. He is the editor of the first edition of Flexible Flat Panel Displays (2005).

<p>A complete treatment of the entire lifecycle of flexible flat panel displays, from raw material selection to commercialization <p>In the newly revised Second Edition of <i>Flexible Flat Panel Displays</i>, a distinguished team of researchers delivers a completely restructured and comprehensive treatment of the field of flexible flat panel displays. With material covering the end-to-end process that includes commercial and technical aspects of the technology, the editors have included contributions that introduce the business, marketing, entrepreneurship, and intellectual property content relevant to flexible flat panel displays. <p>This edited volume contains a brand-new section on case studies using the Harvard Business School format that discusses current and emerging markets in flexible displays, such as an examination of the use of electronic ink and QD Vision in commercial devices. <p>From raw material selection to device prototyping, manufacturing, and commercialization, each stage of the flexible display business is discussed in this insightful new edition. The book also includes: <ul><li> Thorough introductions to engineered films for display technology and liquid crystal optical coatings for flexible displays</li> <li> Comprehensive explorations of organic TFT foils, metallic nanowires, adhesives, and self-healing polymer substrates</li> <li> Practical discussions of flexible glass, AMOLEDs, cholesteric displays, and electronic paper</li> <li> In-depth examinations of the encapsulation of flexible displays, flexible batteries, flexible flat panel photodetectors, and flexible touch screens</li></ul> <p>Perfect for professionals working in the field of display technology with backgrounds in science and engineering, <i>Flexible Flat Panel Displays</i> is also an indispensable resource for professionals with marketing, sales, and technology backgrounds, as well as senior undergraduates and graduate students in engineering and materials science.

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