Barco R5976934 - Manual (Page 35)

3. Design and function
Barco - LC series - R5976934 - user's manual - Revision 08 - April 2008 ________________________________________________________________________________________ 3-3
3.2 Technology
The monitors are based on LCD Super MVA technology. The benefits of this technology are wide viewing angles,
fast video response and high contrast ratio.
MVA stands for Multidomain Vertical Alignment.
3.2.1 Principle of LCD technology
These are the basics used in LCD technology:
• Light can be polarized
• Liquid crystals can transmit polarized light.
• Liquid crystals align themselves when a voltage is applied.
• Liquid crystals change the light's plane of vibration to match their own angle.
There are multiple operating principles of LCD's; one of them is the Multidomain Vertical Alignment which – not
surprising – is based on the Vertical Alignment (VA) technology.
With this operating principle, the LC molecules are completely perpendicular when no voltage is applied, and
thus they don't change the polarization of light. Light simply passes the LC, and is blocked by the front end polar-
izer (since this polarizer is rotated 90° against the back end polarizer which allowed the incident light to pass).
Because the blockage is complete, the quality of black produced this way is excellent!
When voltage is applied, the molecules shift to a horizontal position, producing a white image: the polarization
of the light is changed, and light can pass the front end polarizer.
Since the LC molecules are simply switched between vertical and horizontal alignment, response speeds are very
fast.
As a further development of the VA technology, with MVA technology the LC cell is divided in sub domains where
the molecules are oriented in opposite direction. This widens the viewing angles and enhances the performance.
The following picture shows the basic principle of VA technology:
backlight
V=0
full black
V=Vmax
full white
back polarizer
front polarizer
substrate
substrate
liquid crystal