Optimization of an optical configuration in a vertical alignment liquid crystal cell for wide viewing angle

Abstract

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.

A High Performance Single-Domain LCD With Wide Luminance Distribution

“…Other distribution can be approximated by adjusting the value of . If the incident collimated light has a uniform illuminance (W/m ), according to energy conservation, and are related by (3) The above equation solves with respect to (4) To achieve a desirable , a mapping between the incident position and the emergence angle needs to be established, which is also based on energy conservation (5) Combining (4) and (5), can be solved with respect to (6) In summary, the following three relations jointly define the freeform surface shape: geometrical optics ray tracing relation [see (1)], slope-position relation [see (2)], and energy conservative mapping [see (6)]. …”

“…Extensive efforts [6]- [11] have been devoted to solving the viewing angle problem. These approaches can be categorized into three groups: 1) laminating a compensation film externally to an LCD panel; 2) modifying the internal device structure by creating multiple domains toward different directions; and 3) combination of both.…”