Liquid Crystals Frontiers in Biomedical Applications

Scott J Woltman, Gregory D Jay, Gregory P Crawford978-981-270-545-7, 981-270-545-7

Table of contents :
Contents……Page 16
Preface……Page 8
Acknowledgments……Page 12
Contributors……Page 14
1.1 Introduction……Page 22
1.1.1 Calamitic thermotropic liquid crystals……Page 23
1.1.2 Discotic liquid crystals……Page 27
1.1.3 Polymer liquid crystals……Page 30
Polymeric discotic liquid crystals……Page 31
Reactive mesogen liquid crystals……Page 32
1.1.4 Lyotopic liquid crystals……Page 33
Amphiphilic lyotropic liquid crystals……Page 34
Discotic lyotropic liquid crystals……Page 35
1.2 Basic Properties of Liquid Crystals……Page 36
1.2.1 Surface anchoring conditions……Page 37
1.2.2 Dielectric anisotropy……Page 38
1.2.3 Optical anisotropy……Page 40
1.2.4 Elasticity……Page 41
1.2.5 Basic liquid crystal configurations……Page 42
1.2.6 Optical modeling……Page 43
1.2.8 Eutectic mixtures……Page 44
1.2.9 Non-planar con.nement……Page 45
1.3.1 Liquid crystal display con.gurations……Page 47
1.3.2 Ferroelectric liquid crystals……Page 64
1.3.3 Reflective mode cholesteric LCDs……Page 68
1.3.4 Liquid crystal polymer dispersions……Page 70
1.3.5 Rotating configurations……Page 79
1.4 Grating Applications……Page 80
1.5.1 Thin film polarizers……Page 82
1.5.2 Compensation films……Page 84
1.5.4 Electron transport in discotic liquid crystals……Page 86
1.5.5 Liquid crystal nanotubes……Page 88
1.6 Conclusion……Page 89
Bibliography……Page 92
2.1 Introduction……Page 102
2.2 Display Technology for Medical Imaging Systems……Page 106
2.2.1 Cathode ray tubes……Page 107
2.2.2 Liquid crystal displays……Page 108
2.3 Display DeviceMetrics……Page 110
2.3.1 Luminance……Page 111
2.3.2 Contrast ratio……Page 114
2.3.3 Grayscale……Page 115
2.3.4 Resolution……Page 116
2.3.5 Color……Page 118
2.3.6 Viewing angle……Page 120
Quantitative evaluation of viewing angle……Page 122
Addressing the LCD viewing angle conundrum……Page 124
2.3.7 Veiling glare……Page 127
2.3.8 Uniformity……Page 129
2.5 Optimization of Displays for Medical Applications……Page 130
2.6 Image Processing……Page 132
2.7 3-D displays……Page 133
2.7.1 Passive barrier 3-D displays……Page 134
2.7.2 3-D displays based on lenticular lenses……Page 136
2.7.3 Luminance modulated 3-D displays……Page 139
2.7.4 Active barrier 3-D displays……Page 140
2.7.5 Field-sequential LCD 3-D displays……Page 141
2.7.6 Volumetric 3-D displays……Page 143
2.8 Liquid Crystal Thermography……Page 144
2.9 Future Outlook……Page 149
2.9.1 Head mounted displays……Page 150
2.9.2 Projection displays……Page 152
2.9.3 Acousto-optic liquid crystal sensors……Page 153
2.9.4 Flexible displays……Page 154
2.10 Conclusion……Page 155
Bibliography……Page 158
3.1 Introduction……Page 170
3.2.1 Dispersive devices……Page 174
3.2.2 Nondispersive devices……Page 178
3.2.3 Acousto-optic tunable filters……Page 181
3.2.4 Liquid crystal tunable filters……Page 183
The Lyot .lter……Page 184
Holographically Formed Polymer Dispersed Liquid Crystals……Page 189
Cholesteric liquid crystals……Page 192
Deformed helix ferroelectric liquid crystals……Page 193
Blue phases……Page 195
3.2.5 Hyperspectral imaging in medicine……Page 196
3.2.6 Raman imaging with liquid crystals……Page 203
3.3.1 Operation and advantages……Page 205
3.3.2 Michelson-based FT spectrometers……Page 207
3.3.3 Liquid crystal Fourier transform spectrometers……Page 208
Hadamard Transform Spectroscopy……Page 216
3.4.1 Polarimetry and polarization microscopy……Page 218
3.4.2 Stokes parameters and the Mueller matrix……Page 220
3.4.3 Liquid crystals in polarimeters……Page 222
3.4.4 Polarimetric imaging and spectro-polarimeters……Page 224
3.4.5 Liquid crystals in polarization microscopy……Page 226
3.4.6 Polarimetry and polarization imaging in biology……Page 229
3.5.1 Phase contrast and interference microscopy……Page 231
3.5.2 Scanning microscopy……Page 234
3.5.4 Liquid crystal SLM in optical trapping……Page 238
3.5.5 Liquid crystal SLM in adaptive optics……Page 240
Electrically controlled wavefront correction……Page 241
Optically activated wavefront correction……Page 243
3.6 Conclusion……Page 244
Bibliography……Page 246
4.1 Background and Introduction……Page 262
4.1.1 Scope of the problem……Page 265
4.1.2 Engineering a solution……Page 266
4.2 Current Diagnostic Techniques……Page 268
4.2.1 Molecular diagnostics and microfluidics……Page 270
4.2.2 Quartz crystal microbalance assays……Page 272
4.2.3 Non-liquid crystal optical techniques……Page 274
4.3.1 Phospholipids……Page 277
4.3.2 Free surface interactions and surface anchoring……Page 278
4.3.3 Liquid crystal confinement……Page 279
4.4 Biosensors using Liquid Crystal Technology……Page 280
4.4.1 Background — interfaces……Page 281
4.4.2 Liquid crystal biocompatibility……Page 284
4.4.3 Other techniques for liquid crystal biosensors……Page 288
4.4.4 Imaging of protein immobilization……Page 290
4.4.5 Virus detection using liquid crystals……Page 303
4.4.6 Bacterial detection using liquid crystals……Page 306
4.5 Conclusion……Page 307
Bibliography……Page 310
5.1 Introduction……Page 318
5.2.1 The distributed feedback laser……Page 322
Laser dye molecules……Page 324
Lasing in dye systems……Page 325
5.2.3 Photonic crystals……Page 328
5.3 Liquid Crystal Lasers……Page 331
5.3.1 Experimental setup for lasing……Page 332
5.3.2 Cholesteric liquid crystals……Page 333
Basics……Page 334
Methods of tuning and switching……Page 337
Enhancing emission/thresholds……Page 343
Polymeric cholesteric liquid crystal films……Page 349
Elastomeric cholesteric liquid crystal films……Page 355
5.3.3 Other liquid crystal configurations……Page 356
Ferroelectric liquid crystals……Page 357
Lasing in the blue phase……Page 359
Holographic polymer dispersed liquid crystals……Page 361
Liquid crystal polarization gratings……Page 364
Random lasing in liquid crystal systems……Page 365
Liquid crystals as a microcavity defect layer……Page 369
5.4 Liquid Crystal Lasers in Biology and Medicine……Page 372
5.4.1 Lasing in biology……Page 373
Random lasing in biological systems……Page 374
The biocavity laser……Page 376
5.4.2 Lasing in medicine……Page 20
Liquid crystal lasers for bioimaging……Page 378
Photodynamic therapy — an ideal system for liquid crystal lasers……Page 379
5.4.3 Conclusion……Page 381
Bibliography……Page 382
6.1 Introduction……Page 396
6.2 Color……Page 398
6.2.1 Structural color in nature……Page 399
Random scattering……Page 400
Multilayer reflectors……Page 402
Natural occuring liquid crystalline structures……Page 403
Diffraction gratings……Page 404
Photonic crystals……Page 405
6.2.2 Liquid crystal structural color biomimicking……Page 408
Cholesteric structures……Page 409
Blue phases……Page 411
Higher order photonic crystals……Page 413
Colloids and polymer gels……Page 415
6.3.1 Anti-reflection layers in nature……Page 417
6.3.2 Anti-reflection using liquid crystals……Page 419
6.4 Lenses……Page 421
6.4.1 Biological lenses……Page 422
Bulk liquid crystal lenses……Page 424
Liquid crystal microlens arrays……Page 426
Liquid crystal GRIN lenses……Page 427
Liquid crystal GRIN Fresnel lenses……Page 428
6.5 Biotemplating……Page 430
6.6.1 Optical patterning techniques……Page 433
Amplitude holography……Page 434
Polarization holography……Page 436
Photolithography……Page 439
Laser writing of alignment layers……Page 441
6.6.2 Mechanical patterning techniques……Page 442
Microrubbing……Page 443
Atomic force microscopy scribing……Page 444
6.7 Natural Occuring Liquid Crystalline Phases……Page 447
6.8 Conclusion……Page 448
Bibliography……Page 450
7. Actuators and Delivery Systems Leslie J. Shelton, Scott J. Woltman and Gregory P. Crawford……Page 462
7.1 Introduction……Page 463
7.2.2 Reactivemesogens……Page 465
Thermal stimuli for reactive mesogen actuation……Page 466
Electrical stimuli for reactive mesogen actuation……Page 469
Chemical stimuli for reactive mesogen actuation……Page 471
Light driven stimuli for reactive mesogen actuation……Page 472
7.2.3 Elastomers……Page 474
Thermal stimuli for elastomer actuation……Page 475
Light driven stimuli for elastomer actuation……Page 477
Electrical stimuli for elastomer actuation……Page 479
7.2.4 Gels and hydrogels……Page 480
Nematic gels……Page 481
Liquid crystal hydrogels……Page 484
7.2.5 Carbon nanotube doped materials……Page 486
7.3 Actuators……Page 488
7.3.1 Muscles……Page 489
7.3.2 Heart valves……Page 490
7.3.3 Other actuator applications……Page 21
7.4.1 Drug delivery systems with elastomers……Page 494
7.4.2 Drug delivery systems with hydrogels……Page 495
7.5 Liquid Crystalline Contact Lenses……Page 497
7.6 Conclusion……Page 498
Bibliography……Page 500
Index……Page 510