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This paper reviews the advanced optical configurations for in-plane switching (IPS) and vertical alignment (VA) liquid crystal (LC) cells with wide viewing angle in a visible wavelength range. Optical compensation and optimisation to eliminate off-axis light leakage in the dark state is performed on a Poincare sphere using the trigonometric and the Muller matrix method. By optimising the wavelength dispersion of used optical retardation films, we could achieve wide-view characteristics for both the IPS and VA LC cells. In addition, we show the advanced wide-view technology for a reflective LC mode.

This paper investigates the effect of the electrode edge of a patterned vertical alignment (PVA) liquid crystal (LC) device on the viewing angle characteristics. In general, a transmissive LCD applies an LC layer with half‐wave retardation for a bright state and with zero retardation for a dark state. The retardation of the LC layer would be distorted in each point, however, when a voltage is applied because of the non‐uniform voltage distribution in the electrode edge effect. In this paper, the feasibility of the full effect of the electrode edge on the viewing angle property is considered, and the optical viewing angles of the VA LCD with a uniform half‐wave LC layer and the PVA LCD with a practical non‐uniform LC layer are compared.

A bent electrode structure is proposed in the super in‐plane switching (S‐IPS) liquid crystal (LC), as it can re duce the response time without loss of transmittance in the bright state. The electrode angle in each position of the bent electrode was optimized to simultaneously achieve high transmittance and fast response time. The electro‐optical characteristics of the proposed LC cell structure were experimentally compared with those of the conventional cell. It was observed that the response time became over 8% shorter without loss of transmittance when the proposed bent structure was applied.

We propose an optical configuration of a vertical alignment (VA) liquid crystal (LC) cell to eliminate the light leakage in the diagonal direction. VA LC cell has an excellent contrast ratio in the normal direction due to the no phase‐retardation. However, change of the phase‐retardation occurs in all directions, which causes the light leakage and deteriorates the characteristics of the dark state. We designed the LC cell structure composed of multiple combinations with two A‐plates and two C‐plates in order to achieve wide viewing property on the Poincare sphere. From calculations, we show that the proposed structure can improve the viewing angle characteristics by compensating for the light leakage in all directions.

We introduce a novel type of Adobe RGB liquid crystal display (LCD) monitor with pixels composed of red (R), green (G), and blue (B) sub pixels, combined with a typical blue LED chip based white LED backlight. The key is to apply a newly developed deep green colorant to green sub pixel when the transmittance decrease of the LCD panels was minimized for product design. As a result, the new technology makes it possible to reproduce the Adobe RGB coverage of 99.9% as well as to realize slim LCD.

In this paper we calculated optical transmittance of the In-Plane Switching (IPS) liquid crystal (LC) cell with respect to temperature. By considering temperature energy term in the Gibb's free energy, we could achieve the temperature parameters that need to calculate the temperature dependence on the electro-optic characteristics. The calculated temperature parameters permit us to calculate scalar order parameter S with respect to temperature, so that finally we could calculate the optical transmittance of the IPS LC cell as a function of temperature.

We propose an optical structure for a vertical alignment (VA) liquid crystal (LC) cell with a wide viewing angle. The proposed LC cell consists of an A-plate and two C-plates for optical compensation. Optical compensation and optimization to eliminate off-axis light leakage in the entire visible wavelength range are performed on a Poincaré sphere using the Stokes vector and the Muller matrix method. After optimizing the wavelength dispersion of the retardation films that are used, we prove that the proposed VA LC cell can improve the viewing angle and contrast ratio by calculating optical characteristics, particularly in diagonal directions.

Viewing-angle controllable liquid crystal display (LCD) without using an additional panel or pixel division is proposed. In the device, hybrid aligned nematic liquid crystal using a liquid crystal with negative dielectric anisotropy is used. The device shows narrow viewing angle when it is driven only by fringe-electric field, however, it exhibits wide viewing angle if driven by vertical- as well as fringe-electric field. With the approach, the viewing angle of the LCD can be controlled from 120° to 20° in horizontal direction.

In this paper, we propose an optical configuration for a reflective liquid crystal (LC) cell with a single polarizer that can show an excellent contrast ratio by effectively eliminating phase dispersion. The proposed configuration consists of a half-wave retarder, two A-plates, a quarter-wave LC cell and a reflector; the configuration was designed on a Poincare sphere with the trigonometric method. From the calculation, we confirm that this configuration can show a high contrast ratio as compared with the conventional configuration due to the excellent dark state.

Viewing angle control of a patterned vertical alignment (PVA) liquid crystal display using only one panel is investigated. In conventional PVA modes, a vertically aligned liquid crystal (LC) director tilts down in four directions making 45° with respect to crossed polarizers to exhibit a wide viewing angle. In the viewing angle control device, one pixel was divided into two sub-pixels such that the LC director in the main pixel is controlled to be tilted down in multiple directions making an angle with the polarizer, playing the role of main display with the wide viewing angle, while the LC director in the sub-pixel is controlled to be tilted down to the polarizer axis, playing the role of sub-pixel to the viewing angle control for the narrow viewing angle. Using sub-pixel control, light leakage or any type of information such as characters and image can be generated in oblique viewing directions without distorting the image quality in the normal direction, which will prevent others from peeping at the displayed image by overlapping the displayed image with the made image.

We propose an improved pattern structure that can reduce the response time by using strong fringe field in the pattern vertical alignment LCD. We applied an additional buried electrode in the PVA LCD so that we could increase the fringe field on the edge of the electrode. The strong fringe field on the edge of the electrode helps the liquid crystal director in the bulk area to have an appropriate orientation quickly when the voltage is applied. As a result, we could improve the response time effectively. We used the software TechWiz LCD in order to calculate the director configuration and the response time. From the simulation results, we have found that the proposed structure exhibited 74.2% improvement in response time compared to the conventional structure in calculation.

We propose an optical configuration for the reflective liquid crystal (LC) cell with single polarizer that can show excellent contrast ratio by effectively eliminating phase dispersion. The proposed configuration consists of a half-wave retarder, an A-plate, a quarter-wave LC cell and a reflector. We designed this optical configuration on a Poincare sphere with the trigonometric method. From the calculation, we confirm that the proposed configuration provides high contrast ratio over than 2 times compared to the conventional configuration.