TFT LCD Types
TN + film
The 'TN (twisted nematic) + film' 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 to avoid the shadow-trail and ghosting artifacts that were a cause for complaint in the past. 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. Traditional response times were quoted as an ISO standard black > white transition and did not reflect the speed of transitions across grey tones (a much more common transition for liquid crystals to make in practice). Modern use of RTC (Response Time Compensation – Overdrive) technologies has allowed manufacturers to significantly reduce grey to grey (G2G) transitions, while the ISO response time remains practically unchanged. Response times are now quoted in G2G figures, with 4ms and 2ms now being commonplace for TN Film based models. This marketing strategy, combined with the relatively lower cost of production for TN panels, has led to the dominance of TN in the consumer market.
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. They can also use FRC (Frame Rate Control), the less conspicuous of the two. FRC quickly cycles pixels over time to simulate a given shade. These color simulation methods are noticeable to most people and discomforting for some. FRC tends to be most noticeable in darker tones. Dithering has the tendency to appear as if the individual pixels of the LCD were actually visible. Overall, color reproduction and linearity on TN panels is poor. Shortcomings in display color gamut (often referred to as a percentage of the NTSC 1953 color gamut) can also be attributed to backlighting technology. It is not uncommon for displays with CCFL (Cold Cathode Fluorescent Lamps) based lighting to range from 40% to 76% of the NTSC color gamut, whereas displays utilizing white LED backlights may extend past 100% of the NTSC color gamut – a difference quite perceivable by the human eye.
With LCD displays, the transmittance of a pixel is typically not linear with the applied voltage, and the sRGB standard for computer monitors requires a specific nonlinear dependence of the amount of emitted light as a function of the RGB value.
IPS
IPS (in-plane switching) was developed by Hitachi in 1996 to improve on the poor viewing angles and color reproduction of TN panels. Most also support 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. Though color reproduction approaches that of CRTs, the contrast ratio remains relatively weak. S-IPS technology is widely used in panel sizes of 20" and above. LG and Philips remain one of the main manufacturers of S-IPS based panels.
AS-IPS – Advanced Super IPS, also developed by Hitachi in 2002, improves substantially on the contrast ratio of traditional S-IPS panels to the point where they are second only to some S-PVAs. AS-IPS is also a term used for NEC displays (e.g., NEC LCD20WGX2) based on S-IPS technology, in this case, developed by LG.Philips.
A-TW-IPS – Advanced True White IPS, developed by LG.Philips LCD for NEC, is a custom S-IPS panel with a TW (True White) color filter to make white look more natural and to increase color gamut. This is used in professional/photography LCDs.
H-IPS – Released sometime late 2006, was the H-IPS panel which is an evolution of the IPS panel which improves upon its predecessor, the S-IPS panel. The H-IPS panel can be seen in the NEC LCD2690WUXi, Mitsubishi RDT261W 26″ LCD, Planar PX2611W and Apple's newest Aluminum 24" iMac.
So to sum up, the pros/cons of the H-IPS over the S-IPS:
Pros:
Much less backlight bleed.
No purple hue visible at an angle
Backlight bleed improves looking at an angle
Less noise or glitter seen on the panel surface (smoother surface)
Cons:
Still some backlight bleed in areas that are green.
Viewing angles may have sacrificed in order to improve pros.
Image of a (switched on) transreflective color TFT LCD taken under a microscope with reflected light illumination lamp off (top, self-illumination only) and on (bottom).Fringe Field Switching is a technique to accomplish wider viewing angle and transmittance on IPS displays.
MVA
MVA (multi-domain vertical alignment) was originally developed in 1998 by Fujitsu as a compromise between TN and IPS. It achieved fast pixel response (at the time), wide viewing angles, and high contrast at the cost of brightness and color reproduction. Modern MVA panels can offer wide viewing angles (second only to S-IPS technology), good black depth, good color reproduction and depth, and fast response times thanks to the use of RTC technologies. There are several "next generation" technologies based on MVA, including AU Optronics' P-MVA and A-MVA, as well as Chi Mei Optoelectronics' S-MVA.
Analysts predicted that MVA would corner the mainstream market, but instead, TN has risen to dominance. A contributing factor was the higher cost of MVA, along with its slower pixel response (which rises dramatically with small changes in brightness). Cheaper MVA panels can also use dithering/FRC.
PVA
PVA (patterned vertical alignment) and S-PVA (super patterned vertical alignment) are alternative versions of MVA technology offered by Samsung. Developed independently, it offers similar features to MVA, but boasts contrast ratios as high as 3000:1. Value-oriented PVA panels often use dithering/FRC, while S-PVA panels all use at least 8-bit color and do not use any color simulation methods. Some newer S-PVA panels offered by Eizo offer 10-bit color internally, which enables gamma and other corrections with reduced banding. PVA and S-PVA offer good black depth, wide viewing angles and S-PVA also offer fast response times using modern RTC technologies.
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Sian really heartpain. Onli 6 months den got dead pixel le. 
Linear Mode
