TN (Twisted Nematics)
The TN display is the most common consumer display type, due to its low production cost and wide development. The pixel response time on modern TN panels is sufficiently fast to most users; this fast response time has been a heavily marketed aspect of TN displays, although in most cases this number does not reflect performance across the entire range of possible color transitions. Modern use of technologies has allowed manufacturers to significantly reduce grey to grey (G2G) transitions. Response times are now quoted in G2G figures; with 4ms and 2ms now being commonplace for TN based models.
However, color reproduction and linearity on TN panels is poor. The TN display suffers from limited viewing angles, especially in the vertical direction, and most are unable to display the full 16.7 million colors (24-bit truecolor) available from modern graphics cards.
These particular panels, with 6 bits per color channel as opposed to 8, can approach 24-bit color using a dithering method which combines adjacent pixels to simulate the desired shade. Color shifts also cause a loss of shadow detail in dark scenes when viewed directly from the center. As a result, TN panels can’t be used efficiently for photo work (photos display and manipulation).
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PVA (Patterned Vertical Alignment)
PVA was developed by Samsung as an alternative to MVA (see below).The parameters and the development ways of PVA and MVA are so different that PVA can be truly regarded as an independent technology. Color reproduction is not perfect, like with MVA matrices: when you are looking straight at the screen, the matrix “loses”some shades, which return after you deflect your line of sight from the perpendicular a little. This 'off-centre' contrast shift or 'black crush' as it is sometimes referred to as, is the reason why some color enthusiasts prefer IPS based screens.
PVA and S-PVA (super patterned vertical alignment) offers similar features to MVA, but boasts very high contrast ratios such as 3000:1. S-PVA panels all use at least true 8-bit color electronics and do not use any color simulation methods. S-PVA panels offered by Eizo (at least newer ones) use even 10-bit color internally, which enables gamma and other corrections without banding.
PVA and S-PVA can offer good black depth, wide viewing angles and S-PVA can offer additionally fast response times thanks to modern RTC technologies. Overall, PVA panels offer better image quality than TN and MVA at lower price than IPS based panels. PVA is currently used in mid to high-end Eizo, NEC, Apple and LaCie displays, among others.
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IPS (In-Plane Switching
IPS (in-plane switching) was developed by Hitachi in 1996 to improve on the poor viewing angles and color reproduction of TN panels. It also supports true 8-bit color. These improvements came at a loss of response time, which was initially on the order of 50ms. IPS panels were also extremely expensive. IPS has since been superseded by S-IPS (Super-IPS, Hitachi in 1998), which has all the benefits of IPS technology with the addition of improved pixel refresh timing.
S-IPS/H-IPS
S-IPS/H-IPS panels are generally considered the best overall LCD technology for image quality, color accuracy and viewing angles. They are well suited for graphics design and other applications which require accurate and consistent color reproduction. S-IPS panels offer the best viewing angles of any current LCD technology, with wide viewing angles up to 178 degrees. The response time of S-IPS is adequate, ranging from 6ms to 16ms with current panels. This is only slightly slower than TN panels. IPS is currently used in high-end Eizo, NEC, Apple and LaCie displays, among others.
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The color space normally supported by current monitors is sRGB. However, there are now color spaces that are larger than sRGB, such as that used for Hexachrome® printing. In situations like this, where the monitor's color space is smaller than that used in the printed article, a rendering intent is used by the software to compress the printing color space so that it fits into the monitor's color space and the colors are converted for display.