What is an IPS display?
In-Plane Switching (IPS) is a technology that overcomes the viewing limitations and enhances colour reproduction of conventional TFT-LCDs. It is also known as Super TFT.
IPS derives its name from the fact that the liquid-crystal molecules are aligned in parallel with the glass plates, whereas the TN principle adopted in conventional TFT displays is based on perpendicular alignment of the molecules. In an IPS display, the crystals remain oriented in parallel whether the pixel is turned on or off.
Electrodes are placed on the same sheet of glass, instead of on opposing sides, so that when the signal is applied, the crystals rotate horizontally in the same plane.
What is an MVA display?
Multi-Domain Vertical Alignment (MVA) technology differs from both the TN and IPS systems. In the VA system, the liquid crystal molecules are aligned perpendicular to the substrates when no voltage is applied, therefore producing a black image. When voltage is applied, by an electric field, liquid crystal molecules are tilted parallel to the substrate, resulting in a high transmittance of source light.
With no voltage, all the liquid crystal molecules, including those at the boundaries with the substrates, are completely "Vertically Aligned".
In this state, the polarised light passes through the cell without interference by the LC molecules and is then blocked by the front crossed polariser. Because the blockage is complete, the quality of black produced in this way is excellent and the viewer sees this black from all viewing angles.
What are the benefits and negatives of using an IPS-TFT Display?
Benefits of using an IPS
- High contrast leads to blacker background (although MVA technology exhibits deeper black)
- Best viewing angle of all LCD display types with contrast and colour more consistent
- Fantastic readability in sunlight
Negatives of using an IPS
- Power consumption is higher than an MVA display
- IPS-TFT displays come at a higher cost than MVA displays
What are the benefits and negatives of using an MVA Display?
Benefits of using an MVA
- Ability to block colour from backlight when not needed resulting in deeper black backgrounds
- Good colour reproduction capabilities
- Slightly lower price than IPS panels
Negatives of using an MVA
- Lower level of responsiveness
- Can cause moving picture image sticking (ghosting/blurring)
- Off-centre contrast shifting earlier than IPS (when an image viewed from one angle changes or shifts when viewed from a slightly different angle)
- MURA effect, otherwise knows as clouding, when the screen is touched
IPS vs MVA: summary of performance
|£ £ £ £ £
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|Off-Centre Contrast Shift
|MURA (clouding) Effect
As with all display choice, knowing your intended audience, user requirements and environmental conditions, all form part of the initial design process, which will ultimately determine the best display at the right price for your application. Before you make your choice, why not speak with us and we will be happy to talk you through your options.