| Recent years, with the rapid development of liquid crystal disp lay(LCD), the conventional LCD is dif ficult to m eet the requirmet of a lar ge capacity and high fra me display requirement because of the slowly respo nd speed. Blue phase liquid crystal display(BPLCD) is attracted more and more conc ern of m any scholars and because of its sub-microsecond grey to grey respond tim e. And it also has high c ontrast ratio, wide viewing angle and simple fabrication, etc. However, the high operating voltage, hysteresis, and low transmittance restrict the development of BPLCD. In this th esis, the optimum cell gap of BPLCD with dif ferent electrodes’ structures is obtained, and a new electrode structure is designed to reduce the operating voltage and increasing the transmittance.In the first chapter, outlines the current development of LCD and descr ibed in detail the displays’ performance indicators, revelation principles and the developm ent status of Polymer Stabilized Blue Phase Liquid Crysta l Display(PS-BPLCD). According to th e development status of BPLCD, summarizes the BPLCD m ain drawbacks are the high operating voltage, and causes the hysteresis en d the other display qua lity problems. And analyzes the m ain solution to the problem s is to study new high Kerr constant BPLC material, design new electrode’s structure and optimization of the conventional electrodes’ structure.In the second chapter, we made a detail study on the operating thickness of the m ost commonly used and most easily achieved In-Plane-Switching Blue Phase Liquid Crystal Display(IPS-BPLCD). Through the sam e transmittance wall-shape electrode BPLCD can equivalent the equivalent operating thickness of IPS-BPLCD. On this basis, we obtain the optimum cell gaps of IPS-BPLCD with various electrodes’ width and gap; the optimum cell gaps have the minimum operating voltage and relative high transmittance. At the same time, we made a detail study on the el ectric field factor for vari ous saturation birefringence ?ns and saturation electric field Es under various electrodes’ width and gap. the electric field factor is the ratio of the operating voltage saturation electric field Es, witch is dimensionless and is very important indicator of BPLCD to remove hysteresis.In the third chapter, for the high op erating voltage and sm all equivalent cell gap of IPS-BPLCD, we made detail study on the equi valent cell gap and optim um cell gap of the wall-shape protrusion, trapezoid protrusion, do uble penetration protru sion and elliptical protrusion with various electr odes’ width and gap, these four protrusions are commonly used and most possible to achieve production. Then we also obtain the electric structure with various ?ns and Es, in which the electric field factor less than 0.5. and the hysteresis of the BPLCD can be large reduced or disappeared when the electric field factor close or less than 0.5.In the fourth chapter, we propo se a low operating v oltage, high transmittance wedge-shape protrusion BPLCD., which overcom e the drawbacks such as low transmittance of wall-shape protrusion, low operating thickness of the trapezoid protrusion and the unfixed of oblique electrode. W hich achieve the purpose of low operating voltage and high transmittance for the protrusion dielectric constant is too sm all that absorb the electric field heavily. We proposed the protru sion material to be the transparent or ganic adding nanoparticles such as T i O or Ba T i O3, which raise the dielectric constant of protrusion material to the average dielectric constant of BPLC, and then the electric field in the liquid crystal cell can be uniform distribution. We also studied the influence of the optimum dielectric constant of wedge-shape protrusion and the cell gap to the display. With a half-wavelength b iaxial compensation wedge-shape protrusion BPLCD can present a wide viewing angle. We also have designed a detail production process to the wedge-shape protrusion BPLCD, which is very importance to the productione... |
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