A lateral electric field in the ON and OFF states of a liquid crystal display (LCD) can result in a reverse tilt domain in each pixel and, hence, lead to a poor contrast of the display. As the pixel size of the LCD becomes smaller for higher information content, the problem becomes worse. This situation is revealed in silicon microdisplay in which the pixel size is ranged from 10 to 25μm. The design and optimization of this type of microdisplay should take into account an optical model of small pixels with respect to the inhomogeneous electric field....[ Read more ]

A lateral electric field in the ON and OFF states of a liquid crystal display (LCD) can result in a reverse tilt domain in each pixel and, hence, lead to a poor contrast of the display. As the pixel size of the LCD becomes smaller for higher information content, the problem becomes worse. This situation is revealed in silicon microdisplay in which the pixel size is ranged from 10 to 25μm. The design and optimization of this type of microdisplay should take into account an optical model of small pixels with respect to the inhomogeneous electric field.

In the research, a two-dimensional (2D) optical model was developed to analyse the optical performance of reflective LCDs with respect to the lateral field effect. The 2D optical model was applied to calculate for the optical reflectance of small pixels in reflective LC cells on silicon substrate under frame and column inversions of polarities with a pixel pitch of 10μm to 25μm. The mixed twisted nematic and birefringence (MTB) and mixed twisted nematic (MTN) cells were analysed under various cell parameters. The effects of pixel size, rubbing angle and passivation layer were presented on the lateral electric field and, therefore, the display quality. In addition, MTB and MTN cells were made and characterized for comparison with the simulation data.