VA - Vertical Alignment
A type of LCD in which the liquid crystals naturally align vertically to the glass substrates.
As with TN-type LCDs, Vertical Alignment displays rely on changing the orientation of liquid crystal molecules to block or permit the passage of light through the display. As the name suggests, when the display is in off-state, the molecules are aligned vertically on specially textured inner surfaces of the two plates of glass, unlike TN mode displays where the LC molecules are aligned parallel to the glass.
This vertically aligned arrangement prevents light from passing. As a result, the display produces a background that is deep black, enabling VA displays to achieve very high contrast ratios of more than 1000:1, and with sharply delineated characters. Wide viewing angles are another important strength of this type of display.
As with many LCD technologies, a backlight is required as the display works only in the transmissive normally black mode. Almost any backlight colour can be used to deliver the required visual effect, like cool white for a high visual impact and easy readability. Because the background is dark, and the characters are lit, colour effects work particularly well with VA displays. This can be achieved using a special backlight design or with optical filters, and selective colour is also possible to ensure specific characters such as warning symbols, can stand out against other characters to capture the user’s attentions. In this way, VA displays can offer a lower-cost alternative to a full-colour TFT-LCD panel, benefiting from the presence of colour to improve interaction or enhance the user experience.