LCD Type matrix
specification |
Name
················· | Nickname ············· | Year ········ | Inventor
···················· | Advantage ······················································································ ········ | Disadvantages ········································································ | Transmittance/
contrast ratio ······················· | Viewing angle
(V/H)
····················· | Color Depth ················ | Remarks ···························· | Gamma (typ.)
························ | Responce Time
························ |
| TN | Twisted Nematic | 1971 | Schadt & Helfrich | 1. Inexpensive cost and price: One of the key advantages of TN LCD panels stems from the easy implementation of twisted nematic technology. This translates to cheaper manufacturing requirements and simpler production processes, thus further translating into affordability of TN LCD panels and the corresponding consumer electronics products to end consumers.
Note that the introduction and subsequent popularity of twisted nematic technology quickly pushed out other display technologies such as monolithic LED and CRT for most electronics.
Furthermore, because TN LCD panels are easy and cheap to manufacture, not only did they replace LED and CRT display but they have also continued to remain an affordable alternative to modern display technologies such as IPS and AMOLED.
2. Low power consumption: Twisted nematic technology does not require a current to flow to operate. It also runs under low operating voltages. These advantages collectively correspond to low and efficient power consumption, thus making TN LCD panels suitable for use with batteries and low-powered devices.
The power consumption advantage of TN LCD panels has ushered in the era for low-powered and lightweight LCD, thus paving the way for the invention and production of compact and lighter consumer electronics and non-consumer electronic instruments.
3. Better response time and refresh rate: Pixel response time is the duration it takes a single pixel to transition from one state to another. Measured in milliseconds, the lower the number, the better.
On the other hand, refresh rate is the frequency in which the image in a display is refreshed. Measured in hertz, the higher the number, the better.
High response time and low refresh rates create ghosting effects and motion blurs around an image. This is especially true for fast moving images.
Compared against IPS LCD panels, TN LCD panels have shorter response time and higher refresh rate. Pixels in a typical TN LCD panel change their state as fast as two milliseconds compared against the five milliseconds response time of a typical IPS LCD panel. Furthermore, high-end TN LCD panels even have double the usual refresh rate of 120Hz instead of 60Hz.
The better pixel response time and refresh rate advantages of TN LCD panels can enable them to display twice as much information every second. These make TN LCD panels suitable for use in high-end gaming. In fact, some hardcore gamers prefer a TN computer monitor to a VA or IPS monitor due to its responsiveness and better refresh rate. | 1. Poor viewing angle: A notable disadvantage of TN LCD panels is a narrow viewing angle. A user needs to look at a TN panel from a straight up 90-degree angle to maximize its visual performance.
When viewed from other angles, colors will appear duller and images will appear darker on a TN panel. User familiar with different types of LCD can easily discern if a panel is a TN panel through these color shifts and image distortion.
Nonetheless, the restricted viewing angle compels a user to remain sitting dead straight up in front of a TN LCD panel. Doing so can be problematic in larger TN LCD panels in which changing viewing angle is sometimes unavoidable.
2. Poor color reproduction: Among the different types of LCD to include VA panels and IPS panels, TN panels suffer from poor color reproduction.
Apart from the inherent dull color reproduction in twisted nematic LCD technology, especially when compared against vertical alignment or in-plane switching LCD technologies, the problem with the limited viewing angle also produces poor representation of colors.
Poor color reproduction also means that color inaccuracy is another disadvantage of TN panels. This is the reason why TN panels are not suitable for use in color critical tasks such as graphic design, photo manipulation, and video editing, among others.
3. Quality variability: Note that the quality of TN LCD panels depends on manufacturers. Low-end TN LCD panels have the tendency to exhibit extreme instances of other disadvantages such as poor viewing angle and poor color reproduction.
Take note of cheap feature mobile phones as an example. The TN LCD panels used in these products can exhibit extreme color shifts even at slight change in viewing angle.
Images in low-end TN LCD panels can also be indiscernible when viewed under direct sunlight. Note than another disadvantage of TN LCD panels is susceptibility to dead pixels. This becomes more pronounced in cheaper and low-end panels. | | | 6-bit | | | |
| STN | Super Twisted Nematic | 1983 | Brown Boveri Research Center | | | | | monochrome | | | |
| CSTN | Color Super Twisted Nematic | 19950 | Sharp Display | | | | | 6-bit | | | |
| BTN | Best Twisted Nematic | 1995 | Samsung Display | | | | | 6-bit | | | |
| IPS family |
| IPS | Super TFT | 1996 | Hitachi Ltd | 1. Better color reproduction: One of the notable advantages of IPS LCD panels over TN panels is color reproduction that further translates into color accuracy and better image quality.
Note that a typical TN panel only has a 6-bit RGB color depth. This means that it is only capable of producing 262,144 possible colors. On the other hand, a conventional IPS has an 8-bit RGB color depth capable of producing 16.7 million possible colors.
Though another type of LCD technology called virtual alignment or VA has a similar 8-bit RGB color depth, several manufacturers have introduce high-end IPS panels with 16-bit to 24-bit RGB color depth.
Active-matrix organic light-emitting diode or AMOLED display technology is a close competitor of IPS display technology. Between the two however, IPS has better color accuracy because AMOLED panels are prone to producing images with strong or highly saturated colors.
When compared against TN panels and VA panels, as well as AMOLED panels thereby, IPS LCD panels produce more vibrant images and more realistic colors. This advantage means that in-plane switching is an ideal display option for use in multimedia consumption, as well as in color critical work such as photo editing, graphic design, and video editing.
2. Wide viewing angle: TN panels also suffer from very limited viewing angle as demonstrated by poor off-axis image quality. The introduction of VA LCD technology tried to resolve this limitation. But VA panels suffer from color shifts when viewed from a slightly different angle.
Nonetheless, wide viewing angle is another advantage of in-plane switching over TN and VA display technologies. Typical IPS LCD panels will produce no image distortion and relatively minimal color shifts when viewed from different angles while high-end IPS panels will display consistent contrast and brightness levels under different viewing angles.
This advantage of IPS panels is made possible because the technology involves the capacity to change the physical behavior of the liquid crystal layer by making the crystal molecules respond to the electric field in parallel to the TFT. This also results in better color reproduction.
For smartphone and tablet applications, the aforementioned advantage means that these portable devices can be held in various angles and eye levels. This advantage also means that television sets or computer monitors with IPS panels offer a better visual experience than other LCD panels.
3. Better sunlight visibility: Colors and images on an IPS panel remain considerably more visible under bright outdoor lights or direct sunlight than other display technologies. This is an advantage of in-plane switching technology over TN and AMOLED display technologies.
The better color reproduction coupled with better viewing angle and backlighting make IPS usable or viewable under direct sunlight. Note that TN panels suffer from poor visibility under direct sunlight because of its limited color depth. AMOLED panels, on the other hand, have similar problems because of the inapplicability of backlighting.
4. Longer lifespan: Dead pixels are an inherent issue affecting different LCD technologies. The lifespan of IPS LCD panels cannot be generally compared against the lifespan of TN panels or VA panels.
However, it is important to note that TN display technology is easier to implement and thus, TN panels are easier to produce. This further translates to more manufacturers producing TN panels, this increasing the tendency for low manufacturing standards. Some manufacturers are also producing low-end TN panels to meet demands for cheaper LCD.
When generally compared against typical TN panels nonetheless, IPS panels might have a longer lifespan. On the other hand, the lifespan of VA panels might be comparable with IPS. Remember that this is an overstatement.
Compared against AMOLED panels however, IPS panels have obvious longer lifespan. Remember that one of the notable limitations of AMOLED is its susceptibility to noticeable pixel degradation and faster screen burn-ins. | 1. Contrast ratio: When compared against TN panels, IPS LCD panels have better contrast ration because it has better color depth. However, VA panels and AMOLED panels have better contrast ratio than IPS panels.
Backlighting can be blocked effectively in a vertical alignment display technology. This produces deeper blacks and subsequently, higher contrast ratio compared to in-plane switching display technology.
On the other hand, AMOLED panels naturally produce deep blacks because they represent the absence of light and thus, the absence of color. This results in higher contrast ratio. Although IPS technology produces intense whites, high-end AMOLED panels can also rival typical IPS panels in this regard.
2. Power consumption: Another disadvantage of IPS panels when compared against TN panels and AMOLED panels is power consumption. In-plane switching technology consumers more power than TN or AMOLED display technologies.
Note that TN panels are suitable for battery-operated and low-powered devices. On the other hand, a typical IPS panel requires 15 percent more power than a TN panel. IPS panels also require a strong backlighting to improve display clarity unlike AMOLED panels.
This drawback means that consumer electronic devices featuring an IPS panel have more power requirements than counterpart devices equipped with TN or AMOLED panels. This affects the overall energy efficiency rating and battery life performance of a specific device.
3. Pixel response time: Other disadvantages of in-plane switching technology are slow pixel response time and low refresh rate. The response time and refresh rate of IPS panels are slower and lower than TN or AMOLED panels.
Pixel response time is the duration it takes a single pixel to transition from one state to another. Refresh rate is the frequency in which the image in a display is refreshed. Slow pixel response time and low refresh rate create ghosting effects and motion blurs around a moving image. In addition, both ghosting effects and motion blurs are more straining to the eyes.
This limitation makes an IPS panel an unsuitable display option for use in fast-paced and competitive gaming. TN display technology has the faster response time and higher refresh rates among existing LCD technologies. This is the reason why some hardcore gamers still prefer TN panels to IPS or VA panels despite having poor color reproduction.
Manufacturers have produced IPS panels with better response times and refresh rates. However, these panels are more expansive than TN panels, thus making them unappealing to budget-conscious consumers.
4. Cost and price: Manufacturing IPS LCD panels is costlier than manufacturing TN panels because of the involved engineering complexity. This higher manufacturing costs results in higher prices for end consumers.
Entry-level laptops such as netbooks, as well as feature phones and budget smartphones are commonly equipped with TN panels. Devices with IPS LCD panels are relatively more expensive. Note that high-grade IPS panels are featured in top-of-the-line products with higher price tags.
Between in-plane switching and AMOLED display technologies however, both are also costly to manufacture and both IPS and AMOLED panels are commonly featured in premium products such as high-end smartphones and tablet computers. | 100/100
Base level | | | Most panels also support true 8-bit per channel color. These improvements came at the cost of a lower response time, initially about 50 ms. IPS panels were also extremely expensive. | | |
| S-IPS | Super - In Plane Switching | 1998 | Hitachi Ltd | Color shift free | | 100/137 | | 8-bit + FRC | IPS has since been superseded by S-IPS (Super-IPS, Hitachi Ltd. in 1998), which has all the benefits of IPS technology with the addition of improved pixel refresh timing. | | |
| AS-IPS | Advanced Super-IPS | 2002 | Hitachi Ltd | High transmittance | | 130/250 | | 8-bit | AS-IPS, also developed by Hitachi Ltd. 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. | | |
| AFSS | Advanced fringe field switching | 2003 | Boe-Hydis
(Hyundai) | Superior performance and colour gamut with high luminosity | | | | | Colour shift and deviation caused by light leakage is corrected by optimizing the white gamut, which also enhances white/grey reproduction. | | For small and medium size special projects. |
| IPS-Pro | IPS-Provectus | 2004 | Hitachi Ltd | High contrast ratio | | 137/313 | | 8-bit | The latest panel from IPS Alpha Technology with a wider color gamut and contrast ratio matching PVA and ASV displays without off-angle glowing. | | |
| H-IPS | Horizontal IPS | 2007 | LG. Display | | | | | 8-bit | Improves contrast ratio by twisting electrode plane layout. Also introduces an optional Advanced True White polarizing film from NEC, to make white look more natural. This is used in professional/photography LCDs. | | |
| IPS-Pro 2 | IPS alpha | 2008 | Hitachi Ltd | High contrast ratio | | | | 8-bit | Next generation of IPS-Pro | | |
| A-TW-IPS | A True White IPS | 2008 | NEC ?? | | | | | 8-bit | | | |
| E-IPS | Enhanced IPS | 2009 | LG. Display | | | | | 8-bit | | | |
| PLS | switching | 2009 | Samsung | | | | | 8-bit | | | |
| P-IPS | Professional IPS | 2010 | LG. Display | | | | | | Offer 1.07 billion colours (30-bit colour depth). More possible orientations per sub-pixel (1024 as opposed to 256) and produces a better true colour depth. | | |
| IPS-Pro 3 | IPS alpha next gen | 2010 | Hitachi Ltd | High contrast ratio | | | | 8-bit | | | |
| S-PLS | Super Plane Line Switching | 2010 | Samsung | | | | | | Similarities to IPS panels and touts improved viewing angles and image quality, increased brightness and lower production costs. | | |
| AH-IPS | Advanced High Performance IPS | 2011 | LG. Display | | | | | 8-bit + FRC | Improved colour accuracy, increased resolution and PPI, and greater light transmission for lower power consumption. | | |
| AH-PLS | Advanced High Performance IPS | 2011 | | | | | | 8-bit | | | |
| AH-IPS | Advanced High Performance IPS | 2011 | LG. Display | | | | | 8-bit + FRC | Improved colour accuracy, increased resolution and PPI, and greater light transmission for lower power consumption. | | |
| AH-PLS | Advanced High Performance IPS | 2011 | | | | | | 8-bit | | | |
| VA family |
| PVA | Patterned Vertical Aligment | 1996 | Samsung | | | | | 8-bit | | | |
| S-PVA | Super Pattern Vertical Alignment | 1997 | Samsung | | | | | 8-bit | | | |
| S-PVA2 | Super Patterned Vertical Alignment 2 | 2006 | Samsung | | | | | 8-bit | | | |
| C-PVA | Circular Patterned Vertical Alignment | 2008 | Samsung | | | | | | | | |
| S-PVA3 | Super Patterned Vertical Alignment 3 | 2009 | Samsung | | | | | 8-bit + FRC | | | |
| MVA | Multi-domain vertical alignment | 1998 | Fujitsu | | | | | | The pixel response times of MVAs rise dramatically with small changes in brightness. Less expensive MVA panels can use dithering and FRC. | | 25ms |
| P-MVA | Premium Multi-domain vertical alignment | 2000 | AU Optronics | | | | | 8-bit + FRC | | | 25ms |
S-MVA
(Super MVA) | Super Multi-domain vertical alignment | 2000 | CMI & Fujitsu | | | | | 8-bit + FRC | | | 25ms |
A-MVA
(Advanced MVA) | Advanced Multi-domain vertical alignment | 2005 | AU Optronics | | | 1300:1 | | 8-bit | | | 25ms |
| A-MVA2 | Advanced Multi-domain vertical alignment 2 | 2007 | AU Optronics | | | 2000/3000:1 | | 8-bit | | | 25ms |
A-MVA3
(PSA) | Advanced Multi-domain vertical alignment 3
| 2008 | AU Optronics | | | 3000/5000:1 | | 8-bit + FRC | | | 25ms |
| | | | | | | | | | | |
| ASV | Axially Symmetric Vertical Alignment
Advanced Super View | 2002 | Sharp | | | | | 8-bit + FRC | It is a VA mode where liquid crystal molecules orient perpendicular to the substrates in the off state. The bottom sub-pixel has continuously covered electrodes, while the upper one has a smaller area electrode in the center of the subpixel. When the field is on, the liquid crystal molecules start to tilt towards the center of the sub-pixels because of the electric field; as a result, a continuous pinwheel alignment (CPA) is formed; the azimuthal angle rotates 360 degrees continuously resulting in an excellent viewing angle. The ASV mode is also called CPA mode. | | |
UV²A
(Optical aligment) | Ulthra Violet vertical Aligment | 2009 | Sharp Display | | | | | 8-bit + FRC | | | |
Новини
Форум
Актуално
сървър
Отговор с цитат
