The viewing angle is a characteristic value of monitors, displays and projection surfaces that indicates the angle from which a viewer can look at the display surface without having to accept certain limitations.
In the case of LCD displays, FLCD displays, plasma displays, TFT displays and OLED displays, the viewing angle plays a role in that color distortions can occur depending on the viewing angle. The viewing angle is defined in DINISO 9241-307 as the angle at which a contrast of 10:1 still remains, which is not very good and which ultimately leads to the not very informative viewing angles, which are sometimes specified as 170° and more.
The color deviations and the reduced contrast with a changed viewing angle are caused by the physics of the liquid crystal and cannot be eliminated, but only reduced by design. For this reason, the hue and color contrast of flat screens change with the deviation of the viewing angle from the ideal. This reference angle is ideal when the viewer looks vertically at the screen. Deviations from the 0° reference reduce color intensity, sharpness and, not least, contrast.
Thanks to improved arrangement of the color pixels and new technologies, the disturbing color distortions of liquid crystal displays are reduced. One method for this is In-Plane Switching( IPS), another is Advanced Super View( ASV), which achieves viewing angles of over 160 ° in all planes with high contrast and good color values. One IPS technology, Advanced High Performance In-Plane Switching( AH-IPS), even achieves a viewing angle of 178 °.