pls lcd vs tft lcd pricelist
Thanks for the display technology development, we have a lot of display choices for our smartphones, media players, TVs, laptops, tablets, digital cameras, and other such gadgets. The most display technologies we hear are LCD, TFT, OLED, LED, QLED, QNED, MicroLED, Mini LED etc. The following, we will focus on two of the most popular display technologies in the market: TFT Displays and Super AMOLED Displays.
TFT means Thin-Film Transistor. TFT is the variant of Liquid Crystal Displays (LCDs). There are several types of TFT displays: TN (Twisted Nematic) based TFT display, IPS (In-Plane Switching) displays. As the former can’t compete with Super AMOLED in display quality, we will mainly focus on using IPS TFT displays.
OLED means Organic Light-Emitting Diode. There are also several types of OLED, PMOLED (Passive Matrix Organic Light-Emitting Diode) and AMOLED (Active Matrix Organic Light-Emitting Diode). It is the same reason that PMOLED can’t compete with IPS TFT displays. We pick the best in OLED displays: Super AMOLED to compete with the LCD best: IPS TFT Display.
Samsung, being the global leader in mobile displays that it is, was understandably a little unnerved by Apple"s IPS LCD-sporting iPhone 4, but now it"s back to the forefront with its brand spanking new Super PLS tech. PLS stands for Plane to Line Switching, which helps Samsung deliver some pretty spectacular viewing angles -- even better than the already stellar ones you"ll find on IPS panels -- while also improving screen brightness by a reported 10 percent. The target market for Super PLS displays will be smartphones and tablets, with a delicious WXGA resolution on offer for the top bidders. Mind you, Samsung also claims production costs are 15 percent lower than comparable IPS tech, meaning that the only thing standing between us and the next new hotness is time -- Sammy expects to begin mass production early next year. Oh, and it"s working on securing a set of 30 patents relating to Super PLS, so don"t go holding out hope for direct competitors from LG or anyone else anytime soon.
Samsung came up with its unique 18:5:9 AMOLED display for the Galaxy S8. LG picked up its old trusted IPS LCD unit for the G6’s display. These display units have been familiar to the usual Indian smartphone buyer. Honor, on the other hand, has just unveiled the new Honor 8 Pro for the Indian market that ships with an LTPS LCD display. This has led to wonder how exactly is this technology different from the existing ones and what benefits does it give Honor to craft its flagship smartphone with. Well, let’s find out.
The LCD technology brought in the era of thin displays to screens, making the smartphone possible in the current world. LCD displays are power efficient and work on the principle of blocking light. The liquid crystal in the display unit uses some kind of a backlight, generally a LED backlight or a reflector, to make the picture visible to the viewer. There are two kinds of LCD units – passive matrix LCD that requires more power and the superior active matrix LCD unit, known to people as Thin Film Transistor (TFT) that draws less power.
The early LCD technology couldn’t maintain the colour for wide angle viewing, which led to the development of the In-Plane Switching (IPS) LCD panel. IPS panel arranges and switches the orientation of the liquid crystal molecules of standard LCD display between the glass substrates. This helps it to enhance viewing angles and improve colour reproduction as well. IPS LCD technology is responsible for accelerating the growth of the smartphone market and is the go-to display technology for prominent manufacturers.
The standard LCD display uses amorphous Silicon as the liquid for the display unit as it can be assembled into complex high-current driver circuits. This though restricts the display resolution and adds to overall device temperatures. Therefore, development of the technology led to replacing the amorphous Silicon with Polycrystalline Silicon, which boosted the screen resolution and maintains low temperatures. The larger and more uniform grains of polysilicon allow faster electron movement, resulting in higher resolution and higher refresh rates. It also was found to be cheaper to manufacture due to lower cost of certain key substrates. Therefore, the Low-Temperature PolySilicon (LTPS) LCD screen helps provide larger pixel densities, lower power consumption that standard LCD and controlled temperature ranges.
The AMOLED display technology is in a completely different league. It doesn’t bother with any liquid mechanism or complex grid structures. The panel uses an array of tiny LEDs placed on TFT modules. These LEDs have an organic construction that directly emits light and minimises its loss by eradicating certain filters. Since LEDs are physically different units, they can be asked to switch on and off as per the requirement of the display to form a picture. This is known as the Active Matrix system. Hence, an Active Matrix Organic Light Emitting Diode (AMOLED) display can produce deeper blacks by switching off individual LED pixels, resulting in high contrast pictures.
The honest answer is that it depends on the requirement of the user. If you want accurate colours from your display while wanting it to retain its vibrancy for a longer period of time, then any of the two LCD screens are the ideal choice. LTPS LCD display can provide higher picture resolution but deteriorates faster than standard IPS LCD display over time.
An AMOLED display will provide high contrast pictures any time but it too has the tendency to deteriorate faster than LCD panels. Therefore, if you are after greater picture quality, choose LTPS LCD or else settle for AMOLED for a vivid contrast picture experience.
When it comes to choosing the right panel type of your LCD monitor, the options are seemingly endless. We’ve discussed the differences between AMOLED and LCD displays as well as the different types of touchscreen monitors that are commonly used for various devices and their benefits. Now it’s time to learn about the different features and specifications of PLS and IPS panels so you can decide which one is the most suitable choice for your specific personal or professional applications.
PLS stands for plane to line switching. Also referred to as Super PLS Panel, this technology boasts superior technological advancements such as a multitude of brightness setting options, crystal-clear image quality, and adjustable viewing angles without breaking the bank.
IPS stands for in-plane switching. It’s one of the most commonly used monitors for LCD displays and it consists of two glass panels that hold a layer of liquid crystals in between them. The liquid crystals become animated and perform predetermined actions such as moving in a specific direction or displaying certain colours when they’re charged with an electric current. These actions result in the high-quality images that appear on your television, laptop, or smartphone screen.
Both LCD monitor panel types have their advantages and disadvantages for various types of applications. Finding out how they work will help you determine which one is the best choice for your needs.
As mentioned, IPS LCD monitors contain hundreds of liquid crystals that are situated between two glass sheets in a parallel formation. As electric currents run through the liquid crystals when the screen is turned on, they become animated and move in different directions and backlighting passes through them. This is what produces the crystal-clear and instantaneous images you see on the screen. The excellent viewing angles are the result of the horizontal movements of the liquid crystals inside the panel.
PLS panels for LCD monitors have been on the market for over a decade and have proven to be a worthy adversary for their IPS predecessors. Although the technology is the same for the most part, IPS does offer some minor improvements. The main difference is that IPS panels offer more optimized liquid molecular alignment, which makes for a slightly better viewing experience. Hence, PLS screens offer 15% more brightness than IPS panel types.
From an aesthetic and logistical standpoint, PLS panel types are also thinner than IPS due to the fact that the glass sheets that hold the liquid crystals in place are positioned much lower in the screen configuration.
When it comes to comparing and contrasting the differences between IPS and PLS LCD monitor panel types, the competition is pretty stiff. Both monitors are fairly similar with the exception that PLS is meant to be an improvement on the previous technology. Here are the key factors that should be considered when deciding which one is the best monitor panel for LCD industrial displays.
PLS monitors offer superior viewing angles when compared to IPS displays. Unlike IPS displays, PLS monitors don’t have any noticeable colour distortions and they have significantly lower production costs.
Unfortunately, PLS and IPS monitors both have a fairly slow response time (the amount of time it takes for liquid crystals to shift from one colour or shade to another). For this reason, neither one is the ideal choice for gaming purposes, but they’re both suitable for graphic design projects that focus more on colour distribution and accuracy than response time.
PLS panel types have been proven to have superior colour distribution and accuracy compared to IPS panel types. PLS displays have a far more expansive colour gamut that’s ideal for users who require the most natural-looking images and colour options.
Backlight bleed occurs when the lights from the back of the screen leak through the edges, which results in uneven lighting or glow. This is a fairly common shortcoming of IPS screens when the brightness is adjusted to a particularly high level and can make for a poor viewing experience. PLS panel types don’t have this problem and offer even lighting regardless of the brightness settings.
The answer is inconclusive. Both IPS and PLS monitor types certainly have their advantages. Although PLS is slightly better in terms of backlighting and faster response times, the margins for improvement are fairly tight. It really just depends on what your preferences are as well as the applications that the monitors are being used for.
Nauticomp Inc.is one of the leading manufacturers and distributors of sophisticated state-of-the-art LCD displays and monitors in North America. Contact us to learn about our various products or to place an order.
The tried and trusted TFT is the display of choice for most industrial designs, but it does have its limitations in viewability and colour vibrancy. But what about the relatively new technology, IPS (in plane switching) which has turned the TFT into a super-TFT? What are the benefits and drawbacks of each?
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.
A TFT display is a form of Liquid Crystal Displaywith thin film transistors for controlling the image formation. The 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. Discover our TFT Products
Because the pixels block light when in the off state (the opposite situation to conventional TFT), IPS TFT exhibits high contrast and the background is true black when the display is powered down.
Display choice really does depend on your application, end user and environment. It may be a higher-grade IPS is needed to satisfy outdoor requirements, or a lower cost standard TFT display is sufficient. Before you make your choice, why speak with us and we will be happy to talk you through your options.
Let’s first start with the basics. An LCD or Liquid Crystal Display is a type of panel that uses liquid crystals which are back-lit. It’s one of the most common and widely-used technology since they are easily manufactured and doesn’t cost a lot to produce.
Short for Thin Film Transistor, TFT LCD is basically an improved version of LCD wherein an extra transistor and capacitor are both attached to each pixel. This is the same active matrix (AM) technology used in AMOLED displays which we’ll discuss later on.
Because of this, TFT LCDs are able to produce images with better contrast than the usual LCDs. They are also still cheap to produce. Although, viewing angles generally aren’t that impressive while color reproduction is a bit altered. They are now commonly used in low-end devices.
If TFT has one sheet of transistor supporting each pixel, LG Display’s IPS or In-Plane Switching LCDs make use of two transistors for each pixel which is then illuminated with a stronger backlight. This results to way better viewing angles than TFT and a more faithful color reproduction. Any image viewed within 178 degree from all four sides will retain clear details.
One downside, though, is that since it uses a more powerful backlight, it requires slightly more power from the battery as compared to handsets that use non-LCD panels. These are used in majority of handsets today.
A Super-Twisted Nematic display is a type of monochrome passive-matrix LCD that has an even lower cost of production than TFT LCDs. It also consumes less power than both the TFT and IPS displays which is a good thing, but the issue here is that it shows lower image quality and slower response time than TFT panels.
Additionally, STN LCDs can also be reflective which makes it visible even under direct sunlight. Because of this, it is being used for inexpensive phones and informational screens of digital devices.
TFD stands for Thin Film Diode which was made as a sort of getting the best of two things. It has the low power consumption of STN LCDs but since it doesn’t yield very impressive picture quality, it made use of the imaging performance of a TFT LCD.
This specific type of screen is from Samsung Mobile Display and was introduced back in 2010. Super PLS (Plane to Line Switching) were made for LCDs and is an improvement to LG Display’s IPS panels. The company claims that Super PLS is ‘about 100%’ better when talking about viewing angles — putting it in the league of AMOLED displays. It is also 10% brighter which would greatly benefit users when used outdoors.
The Active-Matrix Organic Light-Emitting Diode, or simply AMOLED, was started to be used in mobile phones in 2008. As we’ve mentioned earlier, it uses active matrix but this time for OLED pixels which is simply another term for thin-film display technology . It basically generates light upon electrical activation after combining with a TFT array and has all the characteristics of an OLED display like lively color reproduction, high brightness and sharpness, and is lightweight.
One of the noticeable differences of using AMOLED screens is its deep blacks. This is possible since OLED displays are always off by default unlike LCD panels that are always back-lit. Apart from showing true blacks (since the cell is basically turned off), it also consumes less power.
These are some of the reasons why it quickly gained popularity on high-end devices and because of this, more manufacturers have made the switch from TFT LCDs. Of course, it also has some cons to it. AMOLED displays don’t perform as well as back-lit LCDs under direct sunlight and diode degradation happens over time since they are organic.
Two of the main contenders for display technologies that are widely available are AMOLED and LCD. Here in this article, we will be comprising AMOLED vs LCD and find out which one is better for you.
The AMOLED display is similar to the OLED in various factors like high brightness and sharpness, better battery life, colour reproduction, etc. AMOLED display also has a thin film transistor, “TFT” that is attached to each LED with a capacitor.
TFT helps to operate all the pixels in an AMOLED display. This display might have a lot of positives but there are a few negatives too let’s point both of them out.
The LCD stands for “Liquid Crystal Display”, and this display produces colours a lot differently than AMOLED. LCD display uses a dedicated backlight for the light source rather than using individual LED components.
The LCD displays function pretty simply, a series of thin films, transparent mirrors, and some white LED lights that distributes lights across the back of the display.
As we have mentioned, an LCD display always requires a backlight and also a colour filter. The backlight must have to pass through a thin film transistor matrix and a polarizer. So, when you see it, the whole screen will be lit and only a fraction of light gets through. This is the key difference comparing AMOLED vs LCD and this is what differentiates these two display technologies.
The LCD displays are cheaper compared to the AMOLED as there is only one source of light which makes it easier to produce. Most budget smartphones also use LCD displays.
LCD displays have bright whites, the backlight emits lots of light through pixels which makes it easy to read in outdoors. It also shows the “Accurate True to Life” colours, which means it has the colours that reflect the objects of the real world more accurately than others.
LCDs also offer the best viewing angle. Although it may depend on the smartphone you have. But most high-quality LCD displays support great viewing angles without any colour distortion or colour shifting.
The LCD displays can never show the deep blacks like AMOLED. Due to the single backlight, it always has to illuminate the screen making it impossible to show the deep blacks.
The LCDs are also thicker than other displays because of the backlight as it needs more volume. So, LCD smartphones are mostly thicker than AMOLED ones.
Let’s start with the pricing. Most AMOLED display smartphones always cost more than an LCD smartphone. Although the trend is changing a bit. But still, if you want to get a good quality AMOLED display you have to go for the flagship devices.
The colors are also very sharp and vibrant with the AMOLED displays. And they look much better than any LCD display. The brightness is something where LCDs stood ahead of the AMOLED display. So using an LCD display outdoors gives much better results.
Looking at all these factors and comparing AMOLED vs LCD displays, the AMOLED displays are certainly better than the LCDs. Also, the big display OEMs, like Samsung and LG are focusing more the OLED technologies for their future projects. So, it makes sense to look out for AMOLED displays. That being said, if we see further enhancements in the LCD technology in terms of battery efficiency and more, there is no point to cancel them at this moment.
Monitors with this matrix - the most common. First invented LCD monitors were based on technology TN. Of 100 monitors in the world about 90 have TN the matrix. Are the cheapest and simple to manufacture and therefore the most massive.
Able to convey color in 18or 24-x bit range ( 6or 8 bit per channel Rgb), which, although a good indicator in comparison with the first LCD monitors on TNIn our time, this is not enough for high-quality color reproduction.
Based on TN monitors can be considered more eco-friendly in comparison with monitors on other LCD matrixes. They consume the least electricity, due to the use of low-power backlights.
The main goal was to get rid of shortcomings. TN matrices. Later, this technology was replaced by S —IPS(Super —IPS). Monitors with this technology produce Dell, LG, Philips, Nec, ViewSonic, ASUS and Samsung(Pls). The main purpose of these monitors is to work with graphics, photo processing and other tasks that require accurate color reproduction, contrast and standards compliance. sRGB and Adobe RGB. They are mainly used in professional work with 2D / 3D graphics, photo editors, and pre-print masters, but are also popular with those who simply want to please their eyes with a high-quality picture.
- variation IPS from Samsung. Unlike IPSIt is possible to place the pixels more densely, but the contrast suffers (not very successful design of pixels). Contrast no higher 600:1 - the lowest among LCD matrices. Even u TN matrices this figure is higher. Matrices Pls can use any kind of backlight. According to characteristics, more preferable than MVAPVA matrices.
LCD Monitor Screens (Liquid Crystal Display, liquid crystal monitors) are made of a substance (cyanophenyl), which is in a liquid state, but at the same time has some properties inherent in crystalline bodies. In fact, these are liquids that have anisotropic properties (in particular, optical) that are associated with orderliness in the orientation of molecules.
The first working LCD display was created by Fergason in 1970. Prior to this, liquid crystal devices consumed too much energy, their lifespan was limited, and the image contrast was depressing. The new LCD was presented to the public in 1971, and then it received hot approval. Liquid crystals (Liquid Crystal) are organic substances that are capable of changing the amount of transmitted light under voltage. The liquid crystal monitor consists of two glass or plastic plates, between which there is a suspension. The crystals in this suspension are arranged in parallel with respect to each other, thereby allowing light to penetrate through the panel. When an electric current is applied, the arrangement of the crystals changes, and they begin to prevent the passage of light. LCD technology is widely used in computers and projection equipment. The first liquid crystals were notable for their instability and were hardly suitable for mass production. The real development of LCD technology began with the invention of British scientists a stable liquid crystal - biphenyl (Biphenyl). The first-generation liquid crystal displays can be observed in calculators, electronic games and watches. Modern LCD monitors are also called flat panels, active dual-scan arrays, thin-film transistors. The idea of LCD monitors has been in the air for more than 30 years, but the studies that were carried out did not lead to an acceptable result, so LCD monitors have not won the reputation of devices that provide good image quality. Now they are becoming popular - everyone likes their elegant look, thin camp, compactness, economy (15-30 watts), moreover, it is believed that only wealthy and serious people can afford such luxury
There are two types of LCD monitors: DSTN (dual-scan twisted nematic - dual-scan crystal screens) and TFT (thin film transistor - on thin-film transistors), also called passive and active matrices, respectively. Such monitors consist of the following layers: a polarizing filter, a glass layer, an electrode, a control layer, liquid crystals, another control layer, an electrode, a glass layer and a polarizing filter. The first computers used eight-inch (diagonal) passive black and white matrix. With the transition to active matrix technology, the screen size has grown. Almost all modern LCD monitors use panels on thin-film transistors, providing a bright, clear image of a much larger size.
The size of the monitor depends on the working space occupied by it, and, importantly, its price. Despite the well-established classification of LCD monitors depending on the screen size diagonally (15, 17, 19-inch), the classification according to the working resolution is more correct. The fact is that, unlike CRT-based monitors, whose resolution can be changed quite flexibly, LCD displays have a fixed set of physical pixels. That is why they are designed to work with only one resolution, called a worker. Indirectly, this resolution determines the size of the matrix diagonal, however, monitors with the same working resolution may have a different matrix size. For example, monitors with a diagonal of 15 to 16 inches basically have a working resolution of 1024Ѕ768, which means that this monitor actually has a physical 1024 pixels horizontally and 768 pixels vertically. The working resolution of the monitor determines the size of the icons and fonts that will be displayed on the screen. For example, a 15-inch monitor can have a working resolution of 1024Ѕ768 and 1400Ѕ1050 pixels. In the latter case, the physical dimensions of the pixels themselves will be smaller, and since the same number of pixels are used in both cases when forming the standard icon, then at a resolution of 1400Ѕ1050 pixels the icon will be smaller in physical dimensions. For some users, too small icons at high resolution of the monitor may be unacceptable, so when you buy a monitor, you should immediately pay attention to the working resolution. Of course, the monitor is able to display the image in another, different from the working resolution. This mode of operation of the monitor is called interpolation. In the case of interpolation, the image quality is poor. Interpolation mode significantly affects the display quality of screen fonts.
LCD monitors are inherently digital devices, so the native interface for them is considered a digital DVI interface, which can have two types of convectors: DVI-I, combining digital and analog signals, and DVI-D, transmitting only a digital signal. It is considered that DVI is more preferable for connecting an LCD monitor to a computer, although it is also possible to connect via a standard D-Sub connector. DVI-interface is also supported by the fact that in the case of an analog interface double conversion of the video signal takes place: first the digital signal is converted to analog in a video card (D / A conversion), which is then transformed into a digital electronic unit of the LCD monitor itself (ADC conversion), as a result, the risk of various signal distortion increases. Many modern LCD monitors have both D-Sub and DVI connectors, which allows you to simultaneously connect two system units to the monitor. You can also find models with two digital connectors. In low-cost office models, only the standard D-Sub connector is generally present.
The basic component of the LCD matrix are liquid crystals. There are three main types of liquid crystals: smectic, nematic and cholesteric. According to their electrical properties, all liquid crystals are divided into two main groups: the first one includes liquid crystals with positive dielectric anisotropy, and the second with negative dielectric anisotropy. The difference lies in how these molecules react to an external electric field. Molecules with positive dielectric anisotropy are oriented along the field lines of force, while molecules with negative dielectric anisotropy are perpendicular to the lines of force. Nematic liquid crystals have a positive dielectric anisotropy, and smectic, on the contrary, negative. Another remarkable property of LC molecules is their optical anisotropy. In particular, if the orientation of the molecules coincides with the direction of propagation of plane-polarized light, then the molecules have no effect on the plane of polarization of light. If the orientation of the molecules is perpendicular to the direction of light propagation, then the plane of polarization is rotated so as to be parallel to the direction of orientation of the molecules. The dielectric and optical anisotropy of the LC molecules makes it possible to use them as a kind of light modulators that allow the desired image to be formed on the screen. The principle of operation of such a modulator is quite simple and is based on changing the plane of polarization of the light passing through the LCD cell. The LCD cell is located between two polarizers, the polarization axes of which are mutually perpendicular. The first polarizer cuts plane-polarized radiation from the light transmitted from the illumination lamp. If there were no LCD cell, then such plane-polarized light would be completely absorbed by the second polarizer. An LCD cell placed in the path of the transmitted plane-polarized light can rotate the plane of polarization of the transmitted light. In this case, part of the light passes through the second polarizer, that is, the cell becomes transparent (fully or partially). Depending on how you control the rotation of the polarization plane in the LCD cell, there are several types of LCD matrices. So, the LCD cell, placed between two crossed polarizers, allows you to modulate the transmitted radiation, creating a gradation of black and white. To obtain a color image, it is necessary to use three color filters: red (R), green (G) and blue (B), which, being installed on the white propagation path, will allow you to get three basic colors in the right proportions. So, each pixel of an LCD monitor consists of three separate subpixels: red, green, and blue, which are controlled LCD cells and differ only in the filters used, installed between the top glass plate and the output polarizing filter.
The main technologies in the manufacture of LCD displays: TN + film, IPS (SFT) and MVA. These technologies differ in the geometry of surfaces, polymer, control plate and front electrode. Of great importance are the purity and type of polymer with the properties of liquid crystals, applied in specific developments.
The TN-type liquid crystal matrix (Twisted Nematic) is a multi-layer structure consisting of two polarizing filters, two transparent electrodes and two glass plates, between which the nematic-type liquid-crystal substance with positive dielectric anisotropy is located. Special grooves are applied to the surface of the glass plates, which allows creating initially the same orientation of all liquid crystal molecules along the plate. The grooves on both plates are mutually perpendicular, so the layer of liquid crystal molecules between the plates changes its orientation by 90 °. It turns out that LC molecules form a structure twisted in a spiral (Fig. 3), which is why such matrices are called Twisted Nematic. Glass plates with grooves are located between two polarization filters, and the axis of polarization in each filter coincides with the direction of the grooves on the plate. In the normal state, the LCD cell is open because the liquid crystals rotate the plane of polarization of the light passing through them. Therefore, plane-polarized radiation, formed after the passage of the first polarizer, will pass through the second polarizer, since its axis of polarization will be parallel to the direction of polarization of the incident radiation. Under the influence of the electric field created by transparent electrodes, the molecules of the liquid crystal layer change their spatial orientation, lining up along the direction of the field lines of force. In this case, the liquid crystal layer loses the ability to rotate the plane of polarization of the incident light, and the system becomes optically opaque, since all light is absorbed by the output polarizing filter. Depending on the applied voltage between the control electrodes, it is possible to change the orientation of the molecules along the field not completely, but only partially, that is, to adjust the degree of twist of the LC molecules. This, in turn, allows you to change the intensity of the light passing through the LCD cell. Thus, installing a backlight lamp behind the LCD matrix and changing the voltage between the electrodes, you can vary the degree of transparency of one LCD cell. TN matrices are the most common and cheap. They have certain disadvantages: not very large viewing angles, low contrast and the inability to get the perfect black color. The fact is that even with the application of maximum voltage to the cell, it is impossible to unwind the LC molecules and orient them along the field lines of force. Therefore, such matrices, even when the pixel is completely turned off, remain slightly transparent. The second drawback is associated with small viewing angles. To partially eliminate it, a special diffusing film is applied to the monitor surface, which allows to increase the viewing angle. This technology is called TN + Film, which indicates the presence of this film. Finding exactly which type of matrix is used in the monitor is not so easy. However, if the monitor has a “broken” pixel caused by the failure of the transistor controlling the LCD cell, it will always glow brightly (in red, green or blue) in the TN-matrices, since the open pixel in the TN-matrix corresponds to the absence of voltage on the cell. You can recognize a TN matrix by looking at black at maximum brightness — if it’s rather gray than black, then this is probably the TN matrix.
IPS-matrix monitors are also called Super TFT-monitors. A distinctive feature of IPS-matrices is that the control electrodes are located in them in the same plane on the lower side of the LCD cell. In the absence of voltage between the electrodes, the LC molecules are parallel to each other, the electrodes and the polarization direction of the lower polarizing filter. In this state, they do not affect the polarization angle of the transmitted light, and the light is completely absorbed by the output polarizing filter, since the polarization directions of the filters are perpendicular to each other. When voltage is applied to the control electrodes, the generated electric field rotates the LC molecules by 90 ° so that they are oriented along the field lines. If a light is passed through such a cell, then due to the rotation of the polarization plane, the upper polarizing filter will let the light through without interference, that is, the cell will be in the open state (Fig. 4). By varying the voltage between the electrodes, it is possible to force the LC molecules to rotate at any angle, thereby changing the transparency of the cell. In all other respects, IPS cells are similar to TN matrices: a color image is also formed by using three color filters. IPS-matrices have both advantages and disadvantages compared with TN-matrices. The advantage is the fact that in this case it turns out perfectly black, and not gray, as in TN-matrices. Another indisputable advantage of this technology is large viewing angles. The disadvantages of IPS-matrices should be attributed to a pixel response time longer than for TN-matrices. However, we will return to the question of the pixel response time. In conclusion, we note that there are various modifications of IPS-matrices (Super IPS, Dual Domain IPS), allowing to improve their characteristics.
MVA is a development of VA technology, that is, technology with vertical alignment of molecules. In contrast to the TN and IPS matrices, in this case, liquid crystals with negative dielectric anisotropy are used, which are oriented perpendicular to the direction of the electric field lines. In the absence of voltage between the plates of the LCD cell, all liquid crystal molecules are oriented vertically and have no effect on the polarization plane of the transmitted light. Since the light passes through two crossed polarizers, it is completely absorbed by the second polarizer and the cell is in the closed state, while, in contrast to the TN matrix, it is possible to obtain an ideally black color. If a voltage is applied to the electrodes located above and below, the molecules rotate 90 °, orienting themselves perpendicularly to the lines of the electric field. With the passage of plane-polarized light through such a structure, the polarization plane rotates by 90 ° and the light freely moves through the output polarizer, that is, the LCD cell is in the open state. The advantages of the systems with the vertical ordering of molecules are the possibility of obtaining ideally black color (which, in turn, affects the possibility of obtaining high-contrast images) and the short response time of the pixel. In order to increase the viewing angles in systems with vertical molecular ordering, a multi-domain structure is used, which leads to the creation of matrices of the MVA type. The meaning of this technology is that each subpixel is divided into several zones (domains) using special protrusions, which somewhat change the orientation of the molecules, causing them to align with the surface of the protrusion. This leads to the fact that each such domain shines in its direction (within a certain solid angle), and the combination of all directions expands the viewing angle of the monitor. The advantages of MVA-matrices include high contrast (due to the possibility of obtaining perfectly black color) and large viewing angles (up to 170 °). Currently, there are several varieties of MVA technology, such as Samsung"s PVA (Patterned Vertical Alignment), MVA-Premium, and others, which further enhance the performance of MVA matrices.
Today, in LCD monitors, the maximum brightness declared in the technical documentation ranges from 250 to 500 cd / m2. And if the brightness of the monitor is high enough, then this is necessarily indicated in the advertising booklets and presented as one of the main advantages of the monitor. However, just this is one of the pitfalls. The paradox is that you cannot rely on the figures indicated in the technical documentation. This applies not only to brightness, but also to contrast, viewing angles and pixel response time. Not only can they not at all correspond to the values actually observed, sometimes it is generally difficult to understand what these numbers mean. First of all, there are different measurement techniques described in various standards; Accordingly, measurements carried out according to different methods give different results, and you can hardly find out by which method and how the measurements were taken. Here is one simple example. The measured brightness depends on the color temperature, but when they say that the monitor brightness is 300 cd / m2, the question arises: at what color temperature is this maximum brightness reached? Moreover, manufacturers indicate the brightness not for the monitor, but for the LCD matrix, which is not at all the same. To measure the brightness, special reference signals of generators with precisely specified color temperature are used, therefore the characteristics of the monitor itself as the final product may differ significantly from those stated in the technical documentation. But for the user, the characteristics of the monitor itself, and not of the matrix, are of paramount importance. Brightness is a really important feature for an LCD monitor. For example, with insufficient brightness, you can hardly play various games or watch DVD movies. In addition, it will be uncomfortable working behind the monitor in daylight conditions (external illumination). However, on this basis, to conclude that a monitor with a declared brightness of 450 cd / m2 is something better monitor with a brightness of 350 cd / m2, it would be premature. Firstly, as already noted, the declared and real brightness is not the same thing, and secondly, it is quite enough that the LCD monitor has a brightness of 200-250 cd / m2 (but not asserted, but actually observed). In addition, the fact how the brightness of the monitor is regulated is also important. From the point of view of physics, the brightness can be adjusted by changing the brightness of the backlight lamps. This is achieved either by adjusting the discharge current in the lamp (in the monitors, cold cathode fluorescent lamp, CCFL cold cathode fluorescent lamps are used as backlight), or through the so-called pulse-width modulation of the lamp power. With pulse-width modulation, the voltage on the backlight lamp is supplied by pulses of a certain duration. As a result, the illumination lamp does not glow continuously, but only at periodically repeated time intervals, but due to the inertia of vision, it seems that the lamp is constantly lit (the pulse repetition rate is more than 200 Hz). Obviously, by varying the width of the applied voltage pulses, you can adjust the average brightness of the backlight lamp. In addition to adjusting the brightness of the monitor due to the backlight, sometimes this adjustment is carried out by the matrix itself. In fact, a constant component is added to the control voltage on the electrodes of the LCD cell. This allows you to fully open the LCD cell, but does not allow it to completely close. In this case, with an increase in brightness, black ceases to be black (the matrix becomes partially transparent even when the LCD cell is closed).
No less important characteristic of the LCD monitor is its contrast, which is defined as the ratio of brightness white background to the brightness of the black background. Theoretically, the contrast of the monitor should not depend on the brightness level set on the monitor, that is, at any brightness level, the measured contrast should have the same value. Indeed, the brightness of the white background is proportional to the brightness of the backlight lamp. In the ideal case, the ratio of the transmittance of light by the LCD cell in the open and closed state is a characteristic of the LCD cell itself, but in practice this ratio may depend on both the set color temperature and the set brightness level of the monitor. Recently, the contrast of the image on digital monitors has increased markedly, and now this figure often reaches the value of 500: 1. But here everything is not so simple. The fact is that the contrast can be indicated not for the monitor, but for the matrix. However, as experience shows, if a contrast of more than 350: 1 is indicated in a passport, then this is quite enough for normal work.
Reaction time, or pixel response time, as a rule, is indicated in the technical documentation for the monitor and is considered one of the most important characteristics of the monitor (which is not quite right). In LCD monitors, the pixel response time, which depends on the type of matrix, is measured in tens of milliseconds (in the new TN + Film-matrices, the pixel response time is 12 ms), and this leads to blurring the changing picture and can be noticeable by sight. Distinguish between on time and off time of a pixel. By the time the pixel is turned on is the time required for opening the LCD cell, and by the time it is off it is the time needed to close it. When they talk about the response time of a pixel, they understand the total time on and off of a pixel. The on time of the pixel and the time it turns off can vary significantly. When they talk about the response time of a pixel, indicated in the technical documentation on the monitor, they mean the reaction time of the matrix, and not the monitor. In addition, the pixel response time, indicated in the technical documentation, is interpreted differently by different matrix manufacturers. For example, one of the options for interpreting the on (off) time of a pixel is that it is the time of changing the brightness of a pixel from 10 to 90% (from 90 to 10%). So far, speaking of measuring the response time of a pixel, it is implied that we are talking about switching between black and white colors. If there are no questions with black color (the pixel is just closed), then the choice of white color is not obvious. How will the pixel reaction time change if measured when switching between different semitones? This question is of great practical importance. The fact is that switching from black to white or, conversely, in real applications is relatively rare. In most applications, transitions between semitones are implemented, as a rule. And if the switching time between black and white turns out to be less than the switching time between grayscale, then the pixel response time will not have any practical value and it is impossible to focus on this characteristic of the monitor. What conclusion can be drawn from the above? It"s very simple: the pixel response time claimed by the manufacturer does not allow us to unambiguously judge the dynamic response of the monitor. In this sense, it is more correct to speak not about the switching time of a pixel between white and black colors, but about the average switching time of a pixel between semitones.
All monitors are by nature RGB-devices, that is, the color in them is obtained by mixing in different proportions of the three basic colors: red, green and blue. Thus, each LCD pixel consists of three color subpixels. In addition to the fully closed or fully open state of the LCD cell, intermediate states are also possible when the LCD cell is partially open. This allows you to shape the color tone and mix the color shades of the base colors in the right proportions. At the same time, the number of colors reproduced by the monitor theoretically depends on how many color shades can be formed in each color channel. Partial opening of the LCD cell is achieved by applying the required voltage level to the control electrodes. Therefore, the number of reproducible color shades in each color channel depends on how many different voltage levels can be applied to the LCD cell. For the formation of an arbitrary voltage level, you will need to use high-resolution DAC circuits, which is extremely expensive. Therefore, in modern LCD monitors are most often used 18-bit DACs and less often - 24-bit. When using an 18-bit DAC, there are 6 bits for each color channel. This allows you to form 64 (26 = 64) different voltage levels and, accordingly, to obtain 64 color shades in one color channel. All in all, by mixing the color shades of different channels, it is possible to create 262,144 color shades. When using a 24-bit matrix (24-bit DAC scheme), each channel has 8 bits, which makes it possible to form 256 (28 = 256) color shades in each channel, and the whole matrix reproduces 16 777 216 color shades. At the same time, for many 18-bit matrices in the passport it is indicated that they reproduce 16.2 million color shades. What is the matter here and is it possible? It turns out that in 18-bit matrices, due to all sorts of tricks, it is possible to bring the number of color shades closer to what is reproduced by true 24-bit matrices. To extrapolate color shades in 18-bit matrices, two technologies (and their combinations) are used: dithering and frame rate control (FRC). The essence of dithering technology lies in the fact that the missing color shades are obtained by mixing the nearest color shades of neighboring pixels. Consider a simple example. Suppose that a pixel can only exist in two states: open and closed, with the closed state of the pixel forming black, and the open state forming red. If instead of one pixel we consider a group of two pixels, then, in addition to black and red, we can also get an intermediate color, thereby extrapolating from the two-color to the three-color mode. As a result, if initially such a monitor could generate six colors (two for each channel), then after such a dithering, it will reproduce already 27 colors. The dithering scheme has one major drawback: the increase in color shades is achieved by reducing the resolution. In fact, this increases the pixel size, which can adversely affect when drawing the details of the image. The essence of the FRC technology is to manipulate the brightness of individual subpixels with the help of their additional on / off. As in the previous example, it is considered that a pixel can be either black (turned off) or red (turned on). Each subpixel receives a command to turn on with a frame rate, that is, at a frame rate of 60 Hz, each subpixel receives a command to turn on 60 times per second. This allows you to generate red. If, forcibly, to force a pixel to be turned on not 60 times per second, but only 50 (at every 12th cycle, not turning on, but turning off the pixel), then the pixel brightness will be 83% of the maximum, which will allow to form an intermediate color shade of red. Both of the considered methods of extrapolating colors have their drawbacks. In the first case, this is a possible flickering of the screen and a slight increase in the reaction time, and in the second, the probability of losing image details. To distinguish by eye the 18-bit matrix with extrapolation of color from the true 24-bit is quite difficult. At the same time, the cost of a 24-bit matrix is much higher.
Image formation(+) The image is formed by pixels, the number of which depends only on the specific resolution of the LCD panel. Pixel pitch depends only on the size of the pixels themselves, but not on the distance between them. Each pixel is formed individually, which provides excellent focus, clarity and clarity. The image is more holistic and smooth.(~) Pixels are formed by a group of points (triads) or stripes. The pitch of a point or line depends on the distance between points or lines of the same color. As a result, the clarity and clarity of the image strongly depends on the step size of a point or line pitch and on the quality of a CRT.
Monitor interface(+) Digital interface, however, most LCD monitors have a built-in analog interface for connecting to the most common analog outputs of video adapters(-) Analog Interface
Technology does not stand still, and the production of LCD screens is no exception. However, due to the constant development and release of new technologies in the manufacture of screens, as well as due to the special marketing approaches to advertising, many customers may be asked to choose a monitor or TV. better ips or TFT screen?
To answer the question you need to understand what IPS technology is and what a TFT screen is. Only by knowing this, you can understand what the difference between these technologies. This in turn will help you make right choice screen that will fully meet your requirements.
As you may have guessed, TFT is the abbreviated name of the technology. Fully it looks like this - Thin Film Transistor, which in Russian means thin film transistor. In essence, a TFT display is a type of liquid crystal screen that is based on an active matrix. In other words, this is a normal liquid crystal screen with an active matrix. That is, the management of liquid crystal molecules occurs with the help of special thin-film transistors.
IPS - this is also short for In-Plane Switching. This is a kind of active matrix LCD display. This means that the question which is better than TFT or IPS is erroneous, since it is essentially the same thing. More specifically, IPS is a type of FTF display matrix.
Thus, it becomes obvious that tFT difference from IPS is only that TFT is a type of LCD screen with an active matrix, and IPS is the same active matrix in a TFT display, or rather one of the types of matrices. It is worth noting that this matrix is the most common among users worldwide.
The general misconception is that there is some difference between TFT and IPS, it is due to the marketing tricks of sales managers. In an attempt to attract new customers, marketers do not disseminate complete information about technologies, which allows creating the illusion that a completely new development is entering the world. Of course, IPS is a newer development than TN, but choose which better display TFT or IPS is not possible for the above reasons.
The fact that there is no difference between TFT and IPS, you already know, however, there is quite a logical question, TN + Film and TFT IPS, what"s the difference? To answer this question, it is worth considering the advantages of IPS matrices, which are as follows:
Strictly speaking, the IPS matrix is a type of TFT technology, which is used to create LCD screens. TFT is often understood to mean monitors produced by the TN-TFT method. Based on this, you can make a comparison. To get acquainted with the subtleties of the choice of electronics, let us examine the IPS screen, what this concept means. The main thing that distinguishes these displays from the TN-TFT, is the location of the liquid crystal pixels. In the second case, they are arranged in a spiral, are at an angle of ninety degrees horizontally between the two plates. In the first (which interests us most of all) the matrix consists of thin-film transistors. Moreover, the crystals are arranged along the screen plane parallel to each other. Without voltage on them, they do not rotate. In TFTs, each transistor controls one point of the screen.
Let"s take a closer look at the type of screen. The monitors created by this technology have a lot of advantages. First of all, this is a great color rendering. The whole range of shades is bright, realistic. Due to the wide viewing angle, the image does not fade, no matter where you look at it. The monitors have a higher, clear contrast due to the fact that the black color is transmitted just perfectly. It may be noted the following disadvantages possessed by the type of IPS screen. What is, above all, a large energy consumption, a significant drawback. In addition, devices equipped with such screens are expensive, since their production is very expensive. Accordingly, TN-TFTs have diametrically opposed characteristics. They have a smaller viewing angle, the image is distorted when you change the viewpoint It is not very convenient to use them in the sun. The picture darkens, the glare interferes. However, such displays have a fast response, consume less energy and are affordable. Therefore, these monitors are installed in budget models of electronics. Thus, we can conclude in what cases the IPS-screen is suitable, that this is a great thing for fans of movies, photos and videos. However, due to their lower responsiveness, they are not recommended to fans of dynamic computer games.
The IPS technology itself was created by the Japanese company Hitachi in conjunction with NEC. New in it was the arrangement of liquid crystal crystals: not in a spiral (as in TN-TFT), but parallel to each other and along the screen. As a result, such a monitor conveys brighter and more saturated colors. The image is visible even in the open sun. The viewing angle of the IPS-matrix is one hundred and seventy-eight degrees. You can watch the screen from any point: bottom, top, right, left. The picture remains clear. Popular tablets with an IPS screen are released by Apple, they are created on iPS matrix Retina. One inch uses increased pixel density. As a result, the image on the display comes out without grain, the colors are transferred smoothly. According to the developers, the human eye does not notice microparticles, if the pixels are more than 300 ppi. Now devices with IPS-displays are becoming more affordable, they are beginning to supply budget models electronics. Create new types of matrices. For example, MVA / PVA. They have a fast response, wide viewing angle and excellent color reproduction.
LCD TVs on the market appeared a long time ago and everyone had already got used to them. However, every year there are more and more new models, differing in appearance, screen diagonal, interface and not only. In addition, there are such models of liquid crystal displays, which are characterized by a special update rate, types of LEDs and backlighting. However, about everything in turn. For a start, I propose to deal with what it is - LCD monitors.
Probably many of you have heard such things as LCD panels. LCD is an abbreviation that stands for: Liquid Crystal Display. Translated into Russian, this means a liquid crystal display, which means that LCD and LCD panels are one and the same.
Such an LCD monitor has a large number of disadvantages. First, they have poor color rendering due to the use of only 6 bits for each color channel. Most shades are obtained by mixing primary colors. Secondly, the contrast of the LCD monitors and the viewing angle also leaves much to be desired. And if some subpixels or pixels cease to work for you, then most likely they will constantly glow, which few people will appreciate.
E-IPS. Appeared in 2009. This technology has helped improve the viewing angle, brightness and contrast of LCD monitors. In addition, the screen refresh time was reduced to 5 milliseconds and the amount of energy consumed was reduced.
VA. This is the very first kind of matrix for LCD displays, which is a compromise solution between the previous two types of modules. Such matrices best convey the contrast of the image and its colors, but at a certain angle of view some details may disappear and the color balance of white changes.
Plasma or gas discharge lamps. Initially, all LSD monitors had a backlight of one or more lamps. Most of these lamps had a cold cathode and were called CCFL. Later started using EEFL lamps. The source of light in such lamps is plasma, which appears as a result of an electrical discharge passing through a gas. You should not confuse LCD TV with plasma, in which each of the pixels is an independent source of light.
For watching movies in 3D format, this refresh rate will be quite enough. At the same time in many TV set the backlight, which has a refresh rate of 480 Hz. It is achieved by using special TFT transistors.