In this section, we have varied the pixel arrangement,
rubbing direction, and LC mode to minimize the fringing
field and improve the color purity of the CF-LCOS microdisplays.
The color purity was improved from 32% NTSC
level of the strippixels to 47% of the delta pixels, to 56% of
the optimal rubbing direction, and to 63% of the low-leakage
MTB mode as shown in Fig. 12. These improvements of
color purity were obtained without sacrifice or without too
much sacrifice of the reflectivity or brightness of the individual
color. The on region of the bright pixel still occupied
most of the pixel area and therefore, the reflectivity of each
color pixel was still high and ranged from 40% to 50%.
Because each color occupies one-third of the pixel array, the
peak reflectivity of the pixel array, or the CF-LCOS microdisplay
was therefore 11.9%, 12.2%, and 11.1%, respectively,
for the red, green, and blue images as already shown
in Fig. 10.