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The problem of a sheet LCD using plastic substrates is the narrow viewing angle of the large retardation of typical plastic materials. We have developed the optical compensation and a new process for plastic IPS-LCD with wide viewing angle.

Polymer-stabilized V-mode Ferroelectric Liquid Crystals (PSV-FLCs) are attractive for a next generation of LC display. However, in the rubbing technique which is conventionally used for LC molecular alignment, the rubbing scratches form on the alignment film surface, and then, the rubbing scratch pattern is clearly observed in the texture of FLC. Therefore, the high contrast ratio cannot be obtained due to the optical leakage. In this research, we introduce the photo-alignment technique to PSV-FLC. As a result, the optical leakage can be largely suppressed by the photo-alignment technique, and thus, the photo-alignment technique is effective to PSV-FLCs.

In this research, we focus on the polymer-stabilized V-mode FLC (PSV-FLC) in which a doped monomer is photocured in the SmA phase. PSV-FLC may show monostable and V-shaped electrooptical characteristics with a grayscale capability. In this paper, we investigate the dependence of the monostable capability on the fabricating conditions such as monomer materials, polymer concentration, and UV energy. Furthermore, in order to increase the contrast ratio, we introduce a photo-alignment technique. As a result, it is found that the monostable capability of PSV-FLC strongly depends on their conditions. Furthermore, the more uniform molecular alignment without rubbing scratch pattern was obtained by using the photo-alignment film.

We investigated an autostereoscopic 3D display using a Liquid Crystal Gradient Refractive Index (LC GRIN) lens, called LCL (Liquid Crystal Lens) 3D display. The characteristics of the LCL 3D display are high luminance and switchable 2D and 3D images by switching between the states of lens and non-lens. The LCL 3D display does not influence the 2D image quality. However, the crosstalk of the LCL 3D display is relatively high compared with other methods used in autostereoscopic 3D displays, such as barrier type, lenticular type, and so on. Therefore, we have investigated the reduction of crosstalk for the LCL 3D display.

We investigate a 3D display using a Liquid Crystal Gradient Refractive Index (LC GRIN) lens and the factors needed to decrease crosstalk. Crosstalk in the latest 3D displays using LC GRIN lenses is 0.6%.

The refractive index distribution of LC GRIN lenses for autostereoscopic 3D displays was investigated. It was clarified that the refractive index distribution forms a parabolic function of the optimum lens conditions. We achieved a minimum crosstalk of 0.6% in an autostereoscopic 3D display with an LC GRIN lens.

The switching process of BiNem liquid crystal displays (LCDs), which has been so far argued, is reexamined from the viewpoints of anchoring breaking and flow effects. By numerical simulation based on the continuum theory of nematic liquid crystals, the switching process between two stable states was investigated by changing the surface anchoring condition of BiNem LCDs to optimize bistable conditions. From the numerical results of the director and the flow distributions, polar anchoring breaking was distinguished clearly from azimuthal anchoring breaking in bistable switching. The bistable switching regime was observed to be limited by the polar anchoring strength at the slave plate; therefore, the polar anchoring strength at the slave plate was optimized for bistable switching. Furthermore, a BiNem cell was fabricated based on the numerical results, and bistable switching was confirmed.

The liquid-crystal molecular order near the rubbed polymer surface is reexamined by the improved torque balance method. The surface azimuthal anchoring strength measured by the improved torque balance method is several times larger than that believed conventionally, considered to be significantly affected by the phase-transition behavior. Based on this result, it can be argued that the correlation between the rubbing strength and the surface azimuthal anchoring strength should be improved in consideration of the mechanism of surface order.

In this study, we focus on vertical alignment ferroelectric liquid crystals (VA-FLCs), because an FLC display with a high contrast ratio is expected. In the VA, although the normal of smectic layers is vertical to the substrate surface, the director of FLC molecules must tilt to the substrate surface at the tilt angle of FLC molecules. Thus, it is usually difficult to obtain a uniform VA in FLCs. We determine the optimum conditions for the fabrication of VA-FLC cells in terms of the tilt angle of FLC molecules, the anchoring strength of the alignment film, and the cell gap. Results indicate that the FLC with a small tilt angle tends to form good VA, which can be obtained by utilizing alignment films with high surface anchoring strengths. Good VA strongly depends on the cell gap.

Polymer-stabilized ferroelectric liquid crystals (PS-FLCs) photocured in the SmA phase can show monostable V-shaped electrooptical characteristics. In this study, we have researched the influence of the fabrication conditions such as polymer concentration, cell gap, and alignment film materials on the monostable electrooptical characteristics of PS-FLCs. As a result, it is confirmed that the monostable capability strongly depends on the polymer concentration. However, the driving voltage increases as the polymer concentration increases. Therefore, to fabricate practicable PS-FLC devices, it is important to investigate the effects of other factors on the monostable capability. From the investigation of the influence of the cell gap and the alignment film materials on the monostable capability of PS-FLCs, it is concluded that the surface anchoring of the alignment film strongly influences the monostable characteristics of PS-FLCs photocured in the SmA phase.

We have already proposed the In-plane switching Twisted nematic (IT) mode. The IT mode can provide the wide viewing angle characteristics. However, the IT mode requires high electric field to obtain high contrast ratio. To improve this problem, we propose two kinds of methods as solution. The conventional IT mode is normally white mode, while the proposal IT mode is normally black. In this paper, the suggested these methods and its performance are evaluated.