pls tft lcd meaning factory
A thin-film-transistor liquid-crystal display (TFT LCD) is a variant of a liquid-crystal display that uses thin-film-transistor technologyactive matrix LCD, in contrast to passive matrix LCDs or simple, direct-driven (i.e. with segments directly connected to electronics outside the LCD) LCDs with a few segments.
In February 1957, John Wallmark of RCA filed a patent for a thin film MOSFET. Paul K. Weimer, also of RCA implemented Wallmark"s ideas and developed the thin-film transistor (TFT) in 1962, a type of MOSFET distinct from the standard bulk MOSFET. It was made with thin films of cadmium selenide and cadmium sulfide. The idea of a TFT-based liquid-crystal display (LCD) was conceived by Bernard Lechner of RCA Laboratories in 1968. In 1971, Lechner, F. J. Marlowe, E. O. Nester and J. Tults demonstrated a 2-by-18 matrix display driven by a hybrid circuit using the dynamic scattering mode of LCDs.T. Peter Brody, J. A. Asars and G. D. Dixon at Westinghouse Research Laboratories developed a CdSe (cadmium selenide) TFT, which they used to demonstrate the first CdSe thin-film-transistor liquid-crystal display (TFT LCD).active-matrix liquid-crystal display (AM LCD) using CdSe TFTs in 1974, and then Brody coined the term "active matrix" in 1975.high-resolution and high-quality electronic visual display devices use TFT-based active matrix displays.
The circuit layout process of a TFT-LCD is very similar to that of semiconductor products. However, rather than fabricating the transistors from silicon, that is formed into a crystalline silicon wafer, they are made from a thin film of amorphous silicon that is deposited on a glass panel. The silicon layer for TFT-LCDs is typically deposited using the PECVD process.
Polycrystalline silicon is sometimes used in displays requiring higher TFT performance. Examples include small high-resolution displays such as those found in projectors or viewfinders. Amorphous silicon-based TFTs are by far the most common, due to their lower production cost, whereas polycrystalline silicon TFTs are more costly and much more difficult to produce.
The twisted nematic display is one of the oldest and frequently cheapest kind of LCD display technologies available. TN displays benefit from fast pixel response times and less smearing than other LCD display technology, but suffer from poor color reproduction and limited viewing angles, especially in the vertical direction. Colors will shift, potentially to the point of completely inverting, when viewed at an angle that is not perpendicular to the display. Modern, high end consumer products have developed methods to overcome the technology"s shortcomings, such as RTC (Response Time Compensation / Overdrive) technologies. Modern TN displays can look significantly better than older TN displays from decades earlier, but overall TN has inferior viewing angles and poor color in comparison to other technology.
The transmittance of a pixel of an LCD panel typically does not change linearly with the applied voltage,sRGB standard for computer monitors requires a specific nonlinear dependence of the amount of emitted light as a function of the RGB value.
Less expensive PVA panels often use dithering and FRC, whereas super-PVA (S-PVA) panels all use at least 8 bits per color component and do not use color simulation methods.BRAVIA LCD TVs offer 10-bit and xvYCC color support, for example, the Bravia X4500 series. S-PVA also offers fast response times using modern RTC technologies.
A technology developed by Samsung is Super PLS, which bears similarities to IPS panels, has wider viewing angles, better image quality, increased brightness, and lower production costs. PLS technology debuted in the PC display market with the release of the Samsung S27A850 and S24A850 monitors in September 2011.
TFT dual-transistor pixel or cell technology is a reflective-display technology for use in very-low-power-consumption applications such as electronic shelf labels (ESL), digital watches, or metering. DTP involves adding a secondary transistor gate in the single TFT cell to maintain the display of a pixel during a period of 1s without loss of image or without degrading the TFT transistors over time. By slowing the refresh rate of the standard frequency from 60 Hz to 1 Hz, DTP claims to increase the power efficiency by multiple orders of magnitude.
Due to the very high cost of building TFT factories, there are few major OEM panel vendors for large display panels. The glass panel suppliers are as follows:
External consumer display devices like a TFT LCD feature one or more analog VGA, DVI, HDMI, or DisplayPort interface, with many featuring a selection of these interfaces. Inside external display devices there is a controller board that will convert the video signal using color mapping and image scaling usually employing the discrete cosine transform (DCT) in order to convert any video source like CVBS, VGA, DVI, HDMI, etc. into digital RGB at the native resolution of the display panel. In a laptop the graphics chip will directly produce a signal suitable for connection to the built-in TFT display. A control mechanism for the backlight is usually included on the same controller board.
The low level interface of STN, DSTN, or TFT display panels use either single ended TTL 5 V signal for older displays or TTL 3.3 V for slightly newer displays that transmits the pixel clock, horizontal sync, vertical sync, digital red, digital green, digital blue in parallel. Some models (for example the AT070TN92) also feature input/display enable, horizontal scan direction and vertical scan direction signals.
New and large (>15") TFT displays often use LVDS signaling that transmits the same contents as the parallel interface (Hsync, Vsync, RGB) but will put control and RGB bits into a number of serial transmission lines synchronized to a clock whose rate is equal to the pixel rate. LVDS transmits seven bits per clock per data line, with six bits being data and one bit used to signal if the other six bits need to be inverted in order to maintain DC balance. Low-cost TFT displays often have three data lines and therefore only directly support 18 bits per pixel. Upscale displays have four or five data lines to support 24 bits per pixel (truecolor) or 30 bits per pixel respectively. Panel manufacturers are slowly replacing LVDS with Internal DisplayPort and Embedded DisplayPort, which allow sixfold reduction of the number of differential pairs.
Kawamoto, H. (2012). "The Inventors of TFT Active-Matrix LCD Receive the 2011 IEEE Nishizawa Medal". Journal of Display Technology. 8 (1): 3–4. Bibcode:2012JDisT...8....3K. doi:10.1109/JDT.2011.2177740. ISSN 1551-319X.
K. H. Lee; H. Y. Kim; K. H. Park; S. J. Jang; I. C. Park & J. Y. Lee (June 2006). "A Novel Outdoor Readability of Portable TFT-LCD with AFFS Technology". SID Symposium Digest of Technical Papers. AIP. 37 (1): 1079–82. doi:10.1889/1.2433159. S2CID 129569963.
AMOLED and TFT are two types of display technology used in smartphones. AMOLED (active-matrix organic light-emitting diode) displays are made up of tiny organic light-emitting diodes, while TFT (Thin-Film Transistor) displays use inorganic thin-film transistors.
AMOLEDs are made from organic materials that emit light when an electric current is passed through them, while TFTs use a matrix of tiny transistors to control the flow of electricity to the display.
Refresh Rate: Another key difference between AMOLED and TFT displays is the refresh rate. The refresh rate is how often the image on the screen is updated. AMOLED screens have a higher refresh rate than TFT screens, which means that they can display images more quickly and smoothly.
Response Time: The response time is how long it takes for the pixels to change from one colour to another. AMOLED screens have a shorter response time than TFT screens..
Colour Accuracy/Display Quality: AMOLED screens are more accurate when it comes to displaying colours. This is because each pixel on an AMOLED screen emits its own light, which means that the colours are more pure and true to life. TFT screens, on the other hand, use a backlight to illuminate the pixels, which can cause the colours to appear washed out or less vibrant.
Viewing Angle: The viewing angle is the angle at which you can see the screen. AMOLED screens have a wider viewing angle than TFT screens, which means that you can see the screen from more angles without the colours looking distorted.
Power Consumption: One of the main advantages of AMOLED displays is that they consume less power than TFT displays. This is because the pixels on an AMOLED screen only light up when they need to, while the pixels on a TFT screen are always illuminated by the backlight.
Production Cost: AMOLED screens are more expensive to produce than TFT screens. This is because the manufacturing process for AMOLED screens is more complex, and the materials used are more expensive.
Availability: TFT screens are more widely available than AMOLED screens and have been around for longer. They are typically used in a variety of devices, ranging from phones to TVs.
Usage: AMOLED screens are typically used in devices where power consumption is a concern, such as phones and wearable devices. TFT screens are more commonly used in devices where image quality is a higher priority, such as TVs and monitors.
AMOLED and TFT are two different types of display technology. AMOLED displays are typically brighter and more vibrant, but they are more expensive to produce. TFT displays are cheaper to produce, but they are not as bright or power efficient as AMOLED displays.
The display technology that is best for you will depend on your needs and preferences. If you need a screen that is bright and vibrant, then an AMOLED display is a good choice. If you need a screen that is cheaper to produce, then a TFT display is a good choice. However, if you’re worried about image retention, then TFT may be a better option.
When compared to the ordinary LCD, TFT LCD gives very sharp and crisp picture/text with shorter response time. TFT LCD displays are used in more and more applications, giving products better visual presentation.
TFT is an abbreviation for "Thin Film Transistor". The colorTFT LCD display has transistors made up of thin films of Amorphous silicon deposited on a glass. It serves as a control valve to provide an appropriate voltage onto liquid crystals for individual sub-pixels. That is why TFT LCD display is also called Active Matrix display.
A TFT LCD has a liquid crystal layer between a glass substrate formed with TFTs and transparent pixel electrodes and another glass substrate with a color filter (RGB) and transparent counter electrodes. Each pixel in an active matrix is paired with a transistor that includes capacitor which gives each sub-pixel the ability to retain its charge, instead of requiring an electrical charge sent each time it needed to be changed. This means that TFT LCD displays are more responsive.
To understand how TFT LCD works, we first need to grasp the concept of field-effect transistor (FET). FET is a type of transistor which uses electric field to control the flow of electrical current. It is a component with three terminals: source, gate, and drain. FETs control the flow of current by the application of a voltage to the gate, which in turn alters the conductivity between the drain and source.
Using FET, we can build a circuit as below. Data Bus sends signal to FET Source, when SEL SIGNAL applies voltage to the Gate, driving voltage is then created on TFT LCD panel. A sub-pixel will be lit up. A TFT LCD display contains thousand or million of such driving circuits.
Topway started TFT LCD manufacturing more than15 years ago. We produce color TFT LCD display from 1.8 to 15+ inches with different resolutions and interfaces. Here is some more readings about how to choose the right TFT LCD.
If you want to buy a new monitor, you might wonder what kind of display technologies I should choose. In today’s market, there are two main types of computer monitors: TFT LCD monitors & IPS monitors.
The word TFT means Thin Film Transistor. It is the technology that is used in LCD displays. We have additional resources if you would like to learn more about what is a TFT Display. This type of LCDs is also categorically referred to as an active-matrix LCD.
These LCDs can hold back some pixels while using other pixels so the LCD screen will be using a very minimum amount of energy to function (to modify the liquid crystal molecules between two electrodes). TFT LCDs have capacitors and transistors. These two elements play a key part in ensuring that the TFT display monitor functions by using a very small amount of energy while still generating vibrant, consistent images.
Industry nomenclature: TFT LCD panels or TFT screens can also be referred to as TN (Twisted Nematic) Type TFT displays or TN panels, or TN screen technology.
IPS (in-plane-switching) technology is like an improvement on the traditional TFT LCD display module in the sense that it has the same basic structure, but has more enhanced features and more widespread usability.
These LCD screens offer vibrant color, high contrast, and clear images at wide viewing angles. At a premium price. This technology is often used in high definition screens such as in gaming or entertainment.
Both TFT display and IPS display are active-matrix displays, neither can’t emit light on their own like OLED displays and have to be used with a back-light of white bright light to generate the picture. Newer panels utilize LED backlight (light-emitting diodes) to generate their light hence utilizing less power and requiring less depth by design. Neither TFT display nor IPS display can produce color, there is a layer of RGB (red, green, blue) color filter in each LCD pixels to produce the color consumers see. If you use a magnifier to inspect your monitor, you will see RGB color in each pixel. With an on/off switch and different level of brightness RGB, we can get many colors.
Winner. IPS TFT screens have around 0.3 milliseconds response time while TN TFT screens responds around 10 milliseconds which makes the latter unsuitable for gaming
Winner. the images that IPS displays create are much more pristine and original than that of the TFT screen. IPS displays do this by making the pixels function in a parallel way. Because of such placing, the pixels can reflect light in a better way, and because of that, you get a better image within the display.
Winner. While the TFT LCD has around 15% more power consumption vs IPS LCD, IPS has a lower transmittance which forces IPS displays to consume more power via backlights. TFT LCD helps battery life.
Normally, high-end products, such as Apple Mac computer monitors and Samsung mobile phones, generally use IPS panels. Some high-end TV and mobile phones even use AMOLED (Active Matrix Organic Light Emitting Diodes) displays. This cutting edge technology provides even better color reproduction, clear image quality, better color gamut, less power consumption when compared to LCD technology.
This kind of touch technology was first introduced by Steve Jobs in the first-generation iPhone. Of course, a TFT LCD display can always meet the basic needs at the most efficient price. An IPS display can make your monitor standing out.
An AMOLED display consists of an active matrix of OLED pixels generating light (luminescence) upon electrical activation that have been deposited or integrated onto a thin-film transistor (TFT) array, which functions as a series of switches to control the current flowing to each individual pixel.
Typically, this continuous current flow is controlled by at least two TFTs at each pixel (to trigger the luminescence), with one TFT to start and stop the charging of a storage capacitor and the second to provide a voltage source at the level needed to create a constant current to the pixel, thereby eliminating the need for the very high currents required for PMOLED.
TFT backplane technology is crucial in the fabrication of AMOLED displays. In AMOLEDs, the two primary TFT backplane technologies, polycrystalline silicon (poly-Si) and amorphous silicon (a-Si), are currently used offering the potential for directly fabricating the active-matrix backplanes at low temperatures (below 150 °C) onto flexible plastic substrates for producing flexible AMOLED displays. Brightness of AMOLED is determined by the strength of the electron current. The colors are controlled by the red, green and blue light emitting diodes. It is easier to understand by thinking of each pixel is independently colored, mini-LED.
IPS technology is like an improvement on the traditional TFT LCD display module in the sense that it has the same basic structure, but with more enhanced features and more widespread usability compared with the older generation of TN type TFT screen (normally used for low-cost computer monitors). Actually, it is called super TFT. IPS LCD display consists of the following high-end features. It has much wider viewing angles, more consistent, better color in all viewing directions, it has higher contrast, faster response time. But IPS screens are not perfect as their higher manufacturing cost compared with TN TFT LCD.
Utilizing an electrical charge that causes the liquid crystal material to change their molecular structure allowing various wavelengths of backlight to “pass-through”. The active matrix of the TFT display is in constant flux and changes or refreshes rapidly depending upon the incoming signal from the control device.
Tried and trusted TFT technology works by controlling brightness in red, green and blue sub-pixels through transistors for each pixel on the screen. The pixels themselves do not produce light; instead, the screen uses a backlight for illumination.
So, why use a TFT display? Well, it is a mature technology meaning the manufacturing processes are efficient, yields high and cost much lower than AMOLED.
TFT displays also have a much longer lifespan than AMOLED displays and are available in a far greater range of standard sizes, which can be cut down to fit a space restricted enclosure for a relatively low cost adder.
This rise of small, powerful components has also led to significant developments in display technology. The most recent of which, AMOLED, is now the main competitor for the most common display used in quality portable electronics – the TFT–LCD IPS (In-Plane Switching) display. As more factories in the Far East begin to produce AMOLED technology, it seems likely we will enter a battle of TFT IPS versus AMOLED, or LCD vs LED. Where a large percentage of a product’s cost is the display technology it uses, which provides best value for money when you’re designing a new product?
TFT IPSdisplays improved on previous TFT LCD technology, developed to overcome limitations and improve contrast, viewing angles, sunlight readability and response times. Viewing angles were originally very limited – so in-plane switching panels were introduced to improve them.
Modern TFT screens can have custom backlights turned up to whatever brightness that their power limit allows, which means they have no maximum brightness limitation. TFT IPS panels also have the option for OCA bonding, which uses a special adhesive to bond a touchscreen or glass coverlens to the TFT. This improves sunlight readability by preventing light from bouncing around between the layers of the display, and also improves durability without adding excess bulk; some TFT IPS displays now only measure around 2 mm thick.
AMOLED technology is an upgrade to older OLED technology. It uses organic compounds that emit light when exposed to electricity. This means no backlight, which in turn means less power consumption and a reduction in size. AMOLED screens tend to be thinner than TFT equivalents, often produced to be as thin as 1 mm. AMOLED technology also offers greater viewing angles thanks to deeper blacks. Colours tend to be greater, but visibility in daylight is lower than IPS displays.
As manufacturers increasingly focus on smaller devices, such as portable smartphones and wearable technology, the thinness and high colour resolution of AMOLED screens have grown desirable. However, producing AMOLED displays is far more costly as fewer factories offer the technology at a consistent quality and minimum order quantities are high; what capacity there is is often taken up the mobile phone market Full HD TFT IPS displays have the advantage of being offered in industry standard sizes and at a far lower cost, as well as offering superior sunlight visibility.
The competition between displays has benefitted both technologies as it has resulted in improvements in both. For example, Super AMOLED, a marketing brand by Samsung, involves the integration of a touchscreen layer inside the screen, rather than overlaid on it. The backlight in TFT technology means they can never truly replicate the deep blacks in AMOLED, but improvements have been made in resolution to the point where manufacturers like Apple have been happy to use LCD screens in their smartphones, even as they compete with Samsung’s Super AMOLED.
Aside from smartphones, many technologies utilise displays to offer direct interaction with customers. To decide whether TFT LCD will survive the rise of AMOLED technology, we must first recap the advantages of LCD. The backlit quality means that whites are bright and contrast is good, but this will wear down a battery faster than AMOLED. Additionally, cost is a significant factor for LCD screens. They are cheaper, more freely available and are offered in industry standard sizes so can be ordered for new products without difficulty.
It seems hard to deny that AMOLED will someday become the standard for mobile phones, which demand great colour performance and are reliant on battery life. Where size is an issue, AMOLED will also grow to dominance thanks to its superior thinness. But for all other technologies, particularly in industrial applications, TFT-LCD offers bright, affordable display technology that is continually improving as the challenge from AMOLED rises.
In recent years, smartphone displays have developed far more acronyms than ever before with each different one featuring a different kind of technology. AMOLED, LCD, LED, IPS, TFT, PLS, LTPS, LTPO...the list continues to grow.
There are many display types used in smartphones: LCD, OLED, AMOLED, Super AMOLED, TFT, IPS and a few others that are less frequently found on smartphones nowadays, like TFT-LCD. One of the most frequently found on mid-to-high range phones now is IPS-LCD. But what do these all mean?
LCD means Liquid Crystal Display, and its name refers to the array of liquid crystals illuminated by a backlight, and their ubiquity and relatively low cost make them a popular choice for smartphones and many other devices.
LCDs also tend to perform quite well in direct sunlight, as the entire display is illuminated from behind, but does suffer from potentially less accurate colour representation than displays that don"t require a backlight.
Within smartphones, you have both TFT and IPS displays. TFT stands for Thin Film Transistor, an advanced version of LCD that uses an active matrix (like the AM in AMOLED). Active matrix means that each pixel is attached to a transistor and capacitor individually.
The main advantage of TFT is its relatively low production cost and increased contrast when compared to traditional LCDs. The disadvantage of TFT LCDs is higher energy demands than some other LCDs, less impressive viewing angles and colour reproduction. It"s for these reasons, and falling costs of alternative options, that TFTs are not commonly used in smartphones anymore.Affiliate offer
IPS technology (In-Plane Switching) solves the problem that the first generation of LCD displays experience, which adopts the TN (Twisted Nematic) technique: where colour distortion occurs when you view the display from the side - an effect that continues to crop up on cheaper smartphones and tablets.
The PLS (Plane to Line Switching) standard uses an acronym that is very similar to that of IPS, and is it any wonder that its basic operation is also similar in nature? The technology, developed by Samsung Display, has the same characteristics as IPS displays - good colour reproduction and viewing angles, but a lower contrast level compared to OLED and LCD/VA displays.
According to Samsung Display, PLS panels have a lower production cost, higher brightness rates, and even superior viewing angles when compared to their rival, LG Display"s IPS panels. Ultimately, whether a PLS or IPS panel is used, it boils down to the choice of the component supplier.
This is a very common question after "LED" TVs were launched, with the short answer simply being LCD. The technology used in a LED display is liquid crystal, the difference being LEDs generating the backlight.
One of the highlights from TV makers at the CES 2021 tradeshow, mini-LED technology seemed far removed from mobile devices until Apple announced the 2021 iPad Pro. As the name implies, the technique is based on the miniaturization of the LEDs that form the backlight of the screen — which still uses an LCD panel.
Despite the improvement in terms of contrast (and potentially brightness) over traditional LCD/LED displays, LCD/mini-LEDs still divide the screen into brightness zones — over 2,500 in the case of the iPad and 2021 "QNED" TVs from LG — compared to dozens or hundreds of zones in previous-generation FALD (full-array local dimming) displays, on which the LEDs are behind the LCD panel instead of the edges.
AMOLED stands for Active Matrix Organic Light-Emitting Diode. While this may sound complicated it actually isn"t. We already encountered the active matrix in TFT LCD technology, and OLED is simply a term for another thin-film display technology.
OLED is an organic material that, as the name implies, emits light when a current is passed through it. As opposed to LCD panels, which are back-lit, OLED displays are "always off" unless the individual pixels are electrified.
This means that OLED displays have much purer blacks and consume less energy when black or darker colours are displayed on-screen. However, lighter-coloured themes on AMOLED screens use considerably more power than an LCD using the same theme. OLED screens are also more expensive to produce than LCDs.
Because the black pixels are "off" in an OLED display, the contrast ratios are also higher compared to LCD screens. AMOLED displays have a very fast refresh rate too, but on the downside are not quite as visible in direct sunlight as backlit LCDs. Screen burn-in and diode degradation (because they are organic) are other factors to consider.Affiliate offer
Super AMOLED is the name given by Samsung to its displays that used to only be found in high-end models but have now trickled down to more modestly specced devices. Like IPS LCDs, Super AMOLED improves upon the basic AMOLED premise by integrating the touch response layer into the display itself, rather than as an extra layer on top.
Speaking of pixel density, this was one of Apple"s highlights back in 2010 during the launch of the iPhone 4. The company christened the LCD screen (LED, TFT, and IPS) used in the smartphone as "Retina Display", thanks to the high resolution of the panel used (960 by 640 pixels back then) in its 3.5-inch display.
As a kind of consolation prize for iPhone XR and iPhone 11 buyers, who continued relying on LCD panels, Apple classified the display used in the smartphones with a new term, "Liquid Retina". This was later applied also to the iPad Pro and iPad Air models, with the name defining screens that boast a high range and colour accuracy, at least based on the company"s standards.
TFT(Thin Film Transistor) - a type of LCD display that adopts a thin semiconductor layer deposited on the panel, which allows for active control of the colour intensity in each pixel, featuring a similar concept as that of active-matrix (AM) used in AMOLED displays. It is used in TN, IPS/PLS, VA/PVA/MVA panels, etc.
LTPS(Low Temperature PolySilicon) - a variation of the TFT that offers higher resolutions and lower power consumption compared to traditional TFT screens, based on a-Si (amorphous silicon) technology.
IGZO(Indium Gallium Zinc Oxide) - a semiconductor material used in TFT films, which also allows higher resolutions and lower power consumption, and sees action in different types of LCD screens (TN, IPS, VA) and OLED displays
LTPO(Low Temperature Polycrystaline Oxide) - a technology developed by Apple that can be used in both OLED and LCD displays, as it combines LTPS and IGZO techniques. The result? Lower power consumption. It has been used in the Apple Watch 4 and the Galaxy S21 Ultra.
Among televisions, the long-standing featured technology has always been miniLED - which consists of increasing the number of lighting zones in the backlight while still using an LCD panel. There are whispers going around that smartphones and smartwatches will be looking at incorporating microLED technology in their devices soon, with it being radically different from LCD/LED displays as it sports similar image characteristics to that of OLEDs.
In the case of LCD displays, the main advantage lies in the low manufacturing cost, with dozens of players in the market offering competitive pricing and a high production volume. Some brands have taken advantage of this feature to prioritize certain features - such as a higher refresh rate - instead of adopting an OLED panel, such as the Xiaomi Mi 10T.
The two buzzwords the tech world has been chatting about for a number of years now is IPS, (In-Plane Switching) screen technology used for liquid crystal displays or LCD’s for short, and TFT (Thin-Film-Transistor) an active matrix screen technology, which is more expensive, but a sharper image.
Designed in the 1980’s, but not introduced until nearly a decade later, in 1996, by Hitachi, IPS technology is nothing new, and a type of LCD design that affords greater viewing angles and higher-quality color reproduction than the traditional TN or Twisted Nematic LCDs.
TFT (Thin-Film-Transistor) Liquid Crystal Display is a thin display type, where a transistor embedded into each crystal gate; these transistors are then printed on thin-transparent film. The technology was designed to improve image qualities, such as contrast and addressability.
Also designed in the late 1980’s, TFT display technologies is just another variation of LCD displays that offer greater color, contrast, and response times as opposed to available passive matrix LCD’s. One of the primary differences between IPS and TFT display technologies is the cost. IPS is more expensive than TN technology. However, there are some key differences between the two that should be noted.
Before we go into the differences, let’s talk about features of each technology. Note that we’re not talking TVs, computer, or tablets, but screens on a much smaller scale, (think 7” or smaller) which uses different rules to fit that scale. First, it’s interesting to discover that the TFT display technologies is the most common type of color display technology; more monochrome displays still out-sell color, due to lower cost and lower power consumption, however, the narrow poor visibility of TFTs in direct sunlight is their downside; but I’m getting ahead of myself here.
IPS technology has come a long way in regards to cell phones and other LCD screens that are even much smaller. (Picture digital clocks on a radio, microwave, and hand-held games) Some of the features of an IPS screen include:Wider viewing angles – crystals are aligned horizontally rather than vertically, so it allows for better angled viewing, perfect for smaller screens, where you need to rotate the screen for better viewing
TFT display technologies have developed over the years and have become quite popular in tech circles. The features offered with this advancing technology are:Superior color display – for technology that requires it or for consumers that desire color screens
Variety of displays, which can be interfaced through a variety of bus types, including 18 and 24 bit for red/green/blue, LVDS, and 8 bit and 16 bit for a CPU – many controllers allow for two or more different types of interfaces on the same TFT screen
Let me explain. As you can see, both have excellent color display and clarity; however, IPS screens offer greater color reproduction and viewing angles because of the way crystal orientation and polarizers are arranged. In a TFT screen, the structure of the crystals results in angular retardation in the light. The IPS screens thus offer less distortion properties. Other differences include power consumption and cost. With IPS screens, it takes more power (up to 15% more) than with a TFT screen. If you’re on a monitor, such as a computer screen that’s bigger than 7 inches, it will drain your battery faster than if you’re on a 3.5” screen. Regarding cost, IPS panels are more expensive to produce than TFT panels.
If you want the benefits of having a Smartphone without a huge price tag, then TFT devices are your best bet. Another difference is that IPS screens have longer response times than TFT screens, so the lag output is greater. A few other key differences to be aware of are that with IPS panels, you get a bigger variety of panels, as was discussed above, with their super, advanced, and so forth developments, giving the consumer options, and IPS screens that can display 24-bit TrueColor; they also stay color-accurate and remain stable.
Now we will go over the downside of IPS screens, which we briefly touched on above, which includes a major disadvantage: cost. If you’re just looking for an average Smartphone or don’t need all the fancy coloring and clarity for LCD displays, then cost may not be a big factor; however, this is the main reason why IPS technology is beginning to come down. As with every new invention, discovery or technology, demand is everything. Another disadvantage is that colors may not always transcribe correctly or accurately, which may or may not be a deterrent. Also, high resolutions are not always readily available for personal applications. In certain circumstances, the brightness may not be enough, especially in darkness.
Steve Jobs said it best: “Design is not just what it looks like and feels like. Design is how it works.” I tend to agree with him. With TFT display technologies, less energy consumption is a big deal, especially when dealing with bigger screens, and of course less electricity means lower cost, overall. The visibility is sharper, meaning no geometric distortion, which is great for these tired, old eyes. The response time and physical design of the screens are also appealing. TFT displays can also save space and be placed virtually anywhere in an office or home, because of the brightly lit feature and crisp clear images.
Some cons of TFT screens deal with the viewing angle, which create distortion, resulting in a less-than-perfect image. Static resolution, meaning the resolution can’t be changed, may also cause a problem, but newer models seem to have tackled that issue. The accuracy of the display of colors is not perfect, specifically strong blacks and bright whites, so when printing an image, it may not display the spectrum of colors.
And there you have it. In the future, even this superb technology will change and new, more exciting technology will take its place. But until then, IPS & TFT screens are forging ahead with their own advances and improvements, so stayed tune. You don’t want to miss it.
Focus Display Solutions (www.FocusLCDs.com) offers off-the-shelf Color TFT display technologies in both TN and IPS. Many of the color modules contain built in touch panels.
TN Film panels are the mostly widely used in the desktop display market and have been for many years since LCD monitors became mainstream. Smaller sized screens (15″, 17″ and 19″) are almost exclusively limited to this technology in fact and it has also extended into larger screen sizes over the last 7 years or so, now being a popular choice in the 20 – 28″ bracket as well. The TN Film panels are made by many different manufacturers, with the big names all having a share in the market (Samsung, LG.Display, AU Optronics) and being backed up by the other companies including most notably Innolux and Chunghwa Picture Tubes (CPT). You may see different generations of TN Film being discussed, but over the years the performance characteristics have remained similar overall.
The other main reason for using TN Film is that it is fundamentally a responsive technology in terms of pixel latency, something which has always been a key consideration for LCD buyers. It has long been the choice for gaming screens and response times have long been, and still are today, the lowest out of all the technologies overall. Response times typically reach a limit of around 5ms at the ISO quoted black > white > black transition, and as low as 1ms across grey to grey transitions where Response Time Compensation (overdrive) is used. TN Film has also been incorporated into true 120Hz+ refresh rate desktop displays, pairing low response times with high refresh rates for even better moving picture and gaming experiences, improved frame rates and adding 3D stereoscopic content support. Modern 120Hz+ refresh rate screens normally also support NVIDIA 3D Vision 2 and their LightBoost system which brings about another advantage for gaming. You can use the LightBoost strobed backlight system in 2D gaming to greatly reduce the perceived motion blur which is a significant benefit. Some screens even include a native blur reduction mode instead of having to rely on LightBoost ‘hacks’, providing better support for strobing backlights and improving gaming experiences when it comes to perceived motion blur. As a result, TN Film is still the choice for gamer screens because of the low response times and 120Hz+ refresh rate support.
AU Optronics have more recently (around 2005) been working on their latest generation of MVA panel technology, termed ‘Advanced Multi Domain Vertical Alignment’ (AMVA). This is still produced today although a lot of their focus has moved to the similarly named, and not to be confused AHVA (Advanced Hyper Viewing Angle, IPS-type) technology. Compared with older MVA generations, AMVA is designed to offer improved performance including reduced colour washout, and the aim to conquer the significant problem of colour distortion with traditional wide viewing angle technology. This technology creates more domains than conventional multi-domain vertical alignment (MVA) LCD’s and reduces the variation of transmittance in oblique angles. It helps improve colour washout and provides better image quality in oblique angles than conventional VA LCD’s. Also, it has been widely recognized worldwide that AMVA technology is one of the few ways to provide optimized image quality through multiple domains.
AMVA still has some limitations however in practice, still suffering from the off-centre contrast shift you see from VA matrices. Viewing angles are therefore not as wide as IPS technology and the technology is often dismissed for colour critical work as a result. As well as this off-centre contrast shift, the wide viewing angles often show more colour and contrast shift than competing IPS-type panels, although some recent AMVA panel generations have shown improvements here (see BenQ GW2760HS for instance with new “Color Shift-free” technology). Responsiveness is better than older MVA offerings certainly, but remains behind TN Film and IPS/PLS in practice. The Anti-Glare (AG) coating used on most panels is light, and sometimes even appears “semi glossy” and so does not produce a grainy image.
There was the same problem with traditional PVA matrices as with MVA offerings – their response time grew considerably when there’s a smaller difference between the initial and final states of the pixel. Again, PVA panels were not nearly as responsive as TN Film panels. With the introduction of MagicSpeed (Samsung’s overdrive / RTC) with later generations (see below), response times have been greatly improved and are comparable to MVA panels in this regard on similarly spec-ed panels. They still remain behind TN Film panels in gaming use, but the overdrive really has helped improve in this area. There are no PVA panels supporting native 120Hz+ refresh rates and Samsung have no plans to produce any at this time. In fact Samsung’s investment in PVA seems to have been cut back significantly in favour of their IPS-like PLS technology.
In Plane Switching (IPS – also known as ‘Super TFT’) technology was developed by Hitachi in 1996 to try and solve the two main limitations of TN Film matrices at the time, those being small viewing angles and low-quality color reproduction. The name In-Plane Switching comes from the crystals in the cells of the IPS panel lying always in the same plane and being always parallel to the panel’s plane (if we don’t take into account the minor interference from the electrodes). When voltage is applied to a cell, the crystals of that cell all make a 90-degrees turn. By the way, an IPS panel lets the backlight pass through in its active state and shutters it in its passive state (when no voltage is applied), so if a thin-film transistor crashes, the corresponding pixel will always remain black, unlike with TN matrices.
Since their initial production in 1998 S-IPS panels have gained the widest recognition, mostly due to the efforts of LG.Philips LCD (now known as LG.Display), who were outputting rather inexpensive and high-quality 19″ – 30″ matrices. The response time was among the serious drawbacks of the IPS technology – first panels were as slow as 60ms on the “official” black-to-white-to-back transitions (and even slower on grey-to-grey ones!) Fortunately, the engineers dragged the full response time down to 25 ms and then 16ms later, and this total is equally divided between pixel rise and pixel fall times. Moreover, the response time doesn’t greatly grow up on black-to-gray transitions compared to the specification, so some older S-IPS matrices at the time could challenge TN Film panels in this parameter.
Close inspection of modern IPS panels can show this new H-IPS pixel structure, although not all manufacturers refer to their models as featuring an H-IPS panel. Indeed, LG.Display don’t really make reference to this H-IPS version, although from a technical point of view, most modern IPS panels are H-IPS in format. As an example of someone who has referred to this new generation, NEC have used the H-IPS name in their panel specs for models such as the LCD2690WXUi2 and LCD3090WUXi screens.
The following technical report has feedback from the LG.Philips LCD laboratory workers: “Wedesigned a new pixel layout to improve the aperture ratioof IPS mode TFT-LCD (H-IPS). This H-IPS pixel layout design has reducedthe width of side common electrode used to minimize thecross talk and light leakage which is induced by interferencebetween data bus line and side common electrode of conventionalIPS mode. The side common electrodes of a pixel canbe reduced by horizontal layout of inter-digital electrode pattern whereconventional IPS pixel designs have vertical layout of inter-digital electrodes.We realized 15 inch XGA TFT LCD of H-IPS structurewhich has aperture ratio as much as 1.2 times ofcorresponding conventional IPS pixel design.” ©2004 Society for Information Display.
Some spec sheets from LG.Display give some clues as to the differences. The lines separating the sub-pixels are smaller than with H-IPS and therefore the UH-IPS technology has an 18% higher aperture ratio. The drive for increased LCD panel transmissivity is not for the purpose specifically of increasing on screen brightness, but rather to maintain brightness and reduce backlight lamps, inverters, and optical films in order to lower panel costs. LG have used this terminology with some of their LED backlight monitors.
PLS was introduced by Samsung at the end of 2010 and designed to compete with LG.Display’s long-established and very popular IPS technology. It is an IPS-type technology and for all intents and purposes can be considered IPS, just being manufactured by another company. Samsung claimed they had reduced production costs compared with IPS by about 15% and so were making a play at the market of IPS panels when it was launched. At the time it was also being dubbed “S-PLS” (Super-PLS) but that name seemed to be dropped quite quickly in favour of just “PLS”. It wasn’t until mid 2011 that the first PLS displays started to appear, fittingly they were manufactured by Samsung themselves. The Samsung S27A850D was the first of its kind and its overall performance certainly reminded users of IPS panels.
Response times are very comparable to IPS matrices, with 5ms G2G being the current lowest spec on paper. There is currently no support for refresh rates above 60Hz from Samsung PLS panels, although there are some Korean manufactured screens which can be over-clocked to 100Hz refresh rates. This is not natively or officially supported though. Contrast ratios are typically around 700 – 900:1 in practice, although can reach up to 1000:1 in some cases as per their spec. Viewing angles are very comparable to IPS as well with wide fields of view and freedom from the off-centre contrast shifts you see from VA panels. From a wide angle dark content has a pale / white glow to it like modern IPS panels, again leading to a fair amount of so-called “PLS-glow” which can be distracting to some users. AG coating is also light, much like the light coating used on modern AH-IPS panels from LG.Display.
All in all, PLS is very comparable in practice to IPS. It should be noted that some display manufacturers market their screens as using an IPS panel, whereas underneath the hood the panel is actually a Samsung PLS matrix. Testament to how close these technologies are really considered although somewhat mis-leading. Samsung have largely moved away from their focus on PVA panels and are concentrating on PLS (and TN Film still) now instead. At the time of writing PLS panels are typically available in sizes between 23 and 27″ with resolutions up to 2560 x 1440. They do also have a 31.5″ panel with Ultra HD 3840 x 2160 available which is currently their largest. They do not currently manufacturer any ultra-wide 21:9 aspect ratio of curved format panels.
In 2012 some PLS based screens started to be marketed using the “AD-PLS” name. It is unclear what is supposed to have changed, if anything, with these recent panel variants. We suspect this is just a marketing name designed to keep up with LG.Display’s change to the “Advanced High-Performance IPS (AH-IPS)” name from the same time. Performance characteristics remain as described in the PLS section above.
Again like Samsung’s PLS technology, AU Optronics have invested in their own IPS-type technology since 2012, dubbed AHVA. This technology is designed by AU Optronics as another alternative to IPS. Confusingly the AHVA name makes it sound like it’s a VA-type panel, which AU Optronics have been manufacturing for many years. It should not be confused with AMVA which is their current “true” VA technology produced. The BenQ BL2710PT was the first display featuring this new technology and gave us some insight into the performance characteristics of AHVA, confirming how closely it resembled an LG.Display IPS panel.
Response time specs reach as low as 4ms G2G on paper but in reality the matrix does not perform any better than the faster IPS or PLS panel versions. Contrast ratios can reach up to the advertised 1000:1 and viewing angles are also very comparable to IPS. There is no off-centre contrast shift like you see on normal VA panels, but a pale glow is visible on dark content from an angle like with IPS/PLS. The AG coating is very light, often semi-glossy.
On some lower quality LCD screens, you can see bright spots in the middle or on the perimeters of screens. This is caused by uneven light distribution. The downside to using backlights, is that black is never true black, because no matter what, light has to be coming through, so it will never have as dark of a screen as an AMOLED screen. Its comparable to being able to slow a car down to 2 mph versus coming to a complete stop.
Each pixel is its own light source, meaning that no backlight is necessary. This allows the screen assembly to be thinner, and have more consistent lighting across the whole display.
FANNAL in-house design & manufacture TFT display for industrial automotive applications. With the great R&D support, we also offer customized services.
FANNAL 7” TFT-LCD display features 800 x 480 resolution and the latest high-efficiency, long-lifetime LED backlights with brightness rating of 1000cd/m2. The display achieves a wide, 80-degree viewing angle in all directions. The new TFT-LCD are designed with a standard RGB interface and offer a wide operating temperature range of -30°C to 85°C and storage temperature range of -40°C to 90°C, customized for automotive applications.
FANNAL new 8” TFT-LCD display offers a display area of 162.048(H) x 121.536(V)mm, high brightness of 600 cd/m² and a wide viewing angle of 80/80/80/80deg. The operating temperature range is another key feature, the display can operate between a standard -10 to +50°C.
For instance, HTC One uses Super LCD3 tech, in its 4.7in screen which gives a resolution of 1920 x 1080 pixels, with pixel density of 469 pixels per inch (ppi). This results in super display in terms of crispness and colour reproduction. HTC says the SLCD technology gives the phone better power management, improved viewing angles and is easier to produce.
The Thin film transistor liquid crystal display (TFT LCD) technology is the most common display technology used in mobile phones. A variant of liquid crystal display (LCD), the technology uses TFT technology to enhance image quality. It offers better image quality and higher resolutions as compared to earlier generation LCD displays.
IPS LCD Stands for In Plane Switching liquid Crystal Display. This technology offers better display quality as compared to the TFT-LCD display. The good part about IPS LCD is that it offers better viewing angles and consumes less power. Due to higher costs, it is found only on high-end smartphones. Apple uses a high resolution (640x960 pixels) version of IPS LCD in its iPhone 4, which is also called Retina Display.
Organic Light Emitting Diode (OLED) display technology is much better as compared to the LCD display technology because of its excellent colour reproduction, faster response times, wider viewing angles, higher brightness and extremely light weight designs.
OLEDs are brighter than LEDs and do not require backlighting like LCDs. Since OLEDs do not require backlighting, they consume much less power than LCDs.
Color boost is simply Moto"s marketing term for their new display. Although it now uses LCD displays, the company fine-tuned its panels to match the saturation of OLED displays while maintaining the higher performance of LCD. It"s somewhere in the middle ground.