lcd panel good tranlate in stock
Again, IPS is the clear winner here. The vertical viewing angles are very similar to the horizontal ones on both IPS and VA panels. Unfortunately, this is one area where TN panels are usually much, much worse. TN monitors degrade rapidly from below, and colors actually inverse - resulting in a negative image that can be distracting. For this reason, if you decide to buy a TN monitor, look for one with an excellent height adjustment, or consider buying a VESA mounting arm, as you should mount TN monitors at eye level. Even when mounted properly, larger TN displays can appear non-uniform at the edges.
There"s usually not much difference between VA and IPS panels in terms of gray uniformity. It"s rare for monitors to have uniformity issues, and even on monitors that perform worse than average, it"s usually not noticeable with regular content. TN monitors tend to perform a bit worse than usual, though, and the top half of the screen is almost always darker than the rest, but that"s an artifact of the bad vertical viewing angles.
Black uniformity tends to vary significantly, even between individual units of the same model, and there"s no single panel type that performs the best. It"s rare for monitors to have good black uniformity, and almost every monitor we"ve tested has some noticeable cloudiness or backlight bleed. IPS and TN panels can look slightly worse due to their low contrast ratios, as the screen can take on more of a bluish tint when displaying dark scenes. Like with contrast, black uniformity issues usually aren"t very noticeable unless you"re looking at dark content and you"re in a dark room. If you only use your monitor in a bright environment, generally speaking, you don"t need to worry about black uniformity.
Historically, TN panels used to have the worst colors, as many of them were cheaper models that only supported 6-bit colors or used techniques like dithering (FRC) to approximate 8-bit colors. Most displays today, including TN models, are at least 8 bit, and many of them are even able to approximate 10-bit colors through dithering. New technologies, like LG"s Nano IPS and Samsung"s Quantum Dot, add an extra layer to the LCD stack and have significantly improved the color gamut of modern IPS and VA displays, leaving TN a bit behind. Between them, NANO IPS is slightly better, as it tends to offer better coverage of the Adobe RGB color space. Although the difference is minor, IPS panels still have a slight edge over VA and TN displays.
Although TN panels have caught up a bit in the SDR color space, they"re far behind when it comes to HDR, so if you"re looking for a good HDR color gamut, avoid TN panels. Between VA and IPS panels, the difference isn"t as significant; however, IPS panels still have a slight edge. The best VA panels top out at around 90% coverage of the DCI P3 color space used by most current HDR content. IPS panels go as high as 98% coverage of DCI P3, rivaling even some of the best TVs on the market. Due to the very high coverage of DCI P3 on both VA and IPS, the difference isn"t that noticeable, though, as most content won"t use the entire color space anyway.
Although not necessarily as noticeable to everyone as the differences in picture quality, there can also be a difference in motion handling between IPS, VA, and TN displays. TN panels historically offered the best gaming performance, as they had the highest refresh rates and extremely fast response times. Manufacturers have found ways to drastically improve the motion handling of VA and IPS panels, though, and the difference isn"t as pronounced.
LCD panel technology has changed drastically over the last few years, and the historical expectations for response time performance don"t necessarily hold anymore. For years, TN monitors had the fastest response times by far, but that"s started to change. New high refresh-rate IPS monitors can be just as fast.
VA panels are a bit of a strange situation. They typically have slightly slower response times overall compared to similar TN or IPS models. It"s especially noticeable in near-black scenes, where they tend to be significantly slower, resulting in dark trails behind fast-moving objects in dark scenes, commonly known as black smear. Some recent VA panels, such as the Samsung Odyssey G7 LC32G75T, get around it by overdriving the pixels. It results in much better dark scene performance but a more noticeable overshoot in brighter areas.
Within each of the three types of LCD we mentioned, other related panel types use the same basic idea but with slight differences. For example, two popular variants of IPS panels include ADS (technically known as ADSDS, or Advanced Super Dimension Switch) and PLS (Plane to Line Switching). It can be hard to tell these panels apart simply based on the subpixel structure, so we"ll usually group them all as IPS, and in the text, we"ll usually refer to them as IPS-like or IPS family. There are slight differences in colors, viewing angles, and contrast, but generally speaking, they"re all very similar.
There"s another display technology that"s growing in popularity: OLED. OLED, or organic light-emitting diode, is very different from the conventional LCD technology we"ve explored above. OLED panels are electro-emissive, which means each pixel emits its own light when it receives an electric signal, eliminating the need for a backlight. Since OLED panels can turn off individual pixels, they have deep, inky blacks with no blooming around bright objects. They also have excellent wide viewing angles, a near-instantaneous response time, and excellent gray uniformity.
OLED panels aren"t perfect, though. There"s a risk of permanent burn-in, especially when there are lots of static elements on screen, like the UI elements of a PC. There aren"t many OLED monitors available, either, but they"ve started to gain popularity as laptop screens and for high-end monitors, but they"re very expensive and hard to find. They"re also not very bright in some cases, especially when large bright areas are visible on screen. The technology is still maturing, and advances in OLED technology, like Samsung"s highly-anticipated QD-OLED technology, are promising.
As you can probably tell by now, no one panel type works best for everyone; it all depends on your exact usage. Although there used to be some significant differences between panel types, as technology has improved, these differences aren"t as noticeable. The two exceptions to this are viewing angles and contrast. If you"re in a dark room, a VA panel that can display deep blacks is probably the best choice. If you"re not in a dark room, you should focus on the other features of the monitor and choose based on the features that appeal to your exact usage. IPS panels are generally preferred for office use, and TN typically offers the best gaming experience, but recent advancements in VA and IPS technology are starting to change those generalizations. For the most part, the differences between each panel type are so minor now that it doesn"t need to be directly factored into your buying decision.
When it comes todisplay technologies such asprojectorsand panels, factors such as resolution and refresh rate are often discussed. But the underlying technology is equally, if not more, important. There are tons of different types of screens, from OLED and LED to TN, VA, and IPS. Learn about the various monitor and television types, from operation to pros and cons!
The most common form of monitor or TV on the market is LCD or Liquid Crystal Display. As the name suggests, LCDs use liquid crystals that alter the light to generate a specific colour. So some form of backlighting is necessary. Often, it’s LED lighting. But there are multiple forms of backlighting.
LCDs have utilized CCFLs or cold cathode fluorescent lamps. An LCD panel lit with CCFL backlighting benefits from extremely uniform illumination for a pretty even level of brightness across the entire screen. However, this comes at the expense of picture quality. Unlike an LED TV, cold cathode fluorescent lamp LCD monitors lack dimming capabilities. Since the brightness level is even throughout the entire array, a darker portion of scenes might look overly lit or washed out. While that might not be as obvious in a room filled with ambient light, under ideal movie-watching conditions, or in a dark room, it’s noticeable. LED TVs have mostly replaced CCFL.
An LCD panel is transmissive rather than emissive. Composition depends on the specific form of LCD being used, but generally, pixels are made up of subpixel layers that comprise the RGB (red-green-blue) colour spectrum and control the light that passes through. A backlight is needed, and it’s usually LED for modern monitors.
Please note that some of the mentioned types may be considered a sub-category of LCD TVs; therefore, some of the names may vary depending on the manufacturer and the market.
1)Film layer that polarizes light entering2)glass substrate that dictates the dark shapes when the LCD screen is on3)Liquid crystal layer4)glass substrate that lines up with the horizontal filter5)Horizontal film filter letting light through or blocking it6)Reflective surface transmitting an image to the viewer
While many newer TVs and monitors are marketed as LED TVs, it’s sort of the same as an LCD TV. Whereas LCD refers to a display type, LED points to the backlighting in liquid crystal display instead. As such, LED TV is a subset of LCD. Rather than CCFLs, LEDs are light-emitting diodes or semiconductor light sources which generate light when a current passes through.
LED TVs boast several different benefits. Physically, LED television tends to be slimmer than CCFL-based LCD panels, and viewing angles are generally better than on non-LED LCD monitors. So if you’re at an angle, the picture remains relatively clear nonetheless. LEDs are alsoextremely long-lasting as well as more energy-efficient. As such, you can expect a lengthy lifespan and low power draw. Chances are you’ll upgrade to a new telly, or an internal part will go out far before any LEDs cease functioning.
Further segmenting LED TVs down, you"ll find TN panels. A TN or twisted nematic display is a type of LED TV that offers a low-cost solution with a low response time and low input lag.
These displays are known for their high refresh rates, ranging from 100Hz to 144Hz or higher. As a result, many monitors marketed towards gamers feature TN technology. The fast response time and low input lag make them ideal for fast-paced action and gaming. However, TN panels have some limitations.
Overall, while TN panels are an affordable and fast option, they may not be the best choice for those looking for accurate colour reproduction and wide viewing angles.
Like TN, IPS or In-plane Switching displays are a subset of LED panels. IPS monitors tend to boast accurate colour reproduction and great viewing angles. Price is higher than on TN monitors, but in-plane switching TVs generally feature a better picture when compared with twisted nematic sets. Latency and response time can be higher on IPS monitors meaning not all are ideal for gaming.
An IPS display aligns liquid crystals in parallel for lush colours. Polarizing filters have transmission axes aligned in the same direction. Because the electrode alignment differs from TN panels, black levels, viewing angles, and colour accuracy is much better. TN liquid crystals are perpendicular.
The pricing of VA monitors varies, but they are typically more expensive than TN monitors and less costly than IPS or OLED monitors. Overall, VA monitors are an excellent option for those looking for a balance between good picture quality and affordability.
A quantum dot LED TV or QLED is yet another form of LED television. But it’s drastically different from other LED variants. Whereas most LED panels use a white backlight, quantum dot televisions opt for blue lights. In front of these blue LEDs sits a thin layer of quantum dots. These quantum dots in a screen glow at specific wavelengths of colour, either red, green, or blue, therefore comprising the entire RGB (red-green-blue) colour spectrum required to create a colour TV image.
An OLED or organic light-emitting diode display isn’t another variation of LED. OLEDs use negatively and positively charged ions for illuminating individual pixels. By contrast, LCD/LED TVs use a backlight that can make an unwanted glow. In OLED display, there are several layers, including a substrate, an anode, a hole injection layer, a hole transport layer, an emissive layer, a blocking layer, an electron transport layer, and a cathode. The emissive layer, comprised of an electroluminescent layer of film, is nestled between an electron-injecting cathode and an electron removal layer, the anode. OLEDs benefit from darker blacks and eschew any unwanted screen glow. Because OLED panels are made up of millions of individual subpixels, the pixels themselves emit light, and it’s, therefore, an emissive display as opposed to a transmissive technology like LCD/LED panels where a backlight is required behind the pixels themselves.
The image quality is top-notch. OLED TVs feature superb local dimming capabilities. The contrast ratio is unrivalled, even by the best of QLEDs, since pixels not used may be turned off. There’s no light bleed, black levels are incredible, excellent screen uniformity, and viewing angles don’t degrade the picture. Unfortunately, this comes at a cost. OLEDs are pricey, and the image isn’t as bright overall when compared to LED panels. For viewing in a darkened room, that’s fine, but ambient lighting isn’t ideal for OLED use.
As you can see, a wide variety of displays are available on the market today, each with their unique advantages and disadvantages. While many monitors and TVs are referred to by various names, such as LED, IPS, VA, TN, or QLED, many are variations of LCD panels. The specific technology used in a display, such as the colour of backlighting and the alignment of pixels, plays a major role in determining the overall picture quality.
So, why would anyone ever buy a TN panel? For starters, they’re cheap. They don’t cost a lot to produce, so they’re often used in the most budget-friendly options. If you don’t value color reproduction or need excellent viewing angles, a TN panel might be fine for your office or study.
TN panels also have the lowest input lag—typically around one millisecond. They can also handle high refresh rates of up to 240 Hz. This makes them an attractive option for competitive multiplayer games—especially eSports, where every split-second counts.
IPS technology was developed to improve upon the limitations of TN panels—most notably, the poor color reproduction and limited viewing angles. As a result, IPS panels are much better than TNs in both of these areas.
In particular, IPS panels have vastly superior viewing angles than TNs. This means you can view IPS panels from extreme angles and still get accurate color reproduction. Unlike TNs, you’ll notice very little shift in color when you view one from a less-than-ideal perspective.
IPS panels are also known for their relatively good black reproduction, which helps eliminate the “washed out” look you get with TN panels. However, IPS panels fall short of the excellent contrast ratios you’ll find on VAs.
While high refresh rates were typically reserved for TNs, more manufacturers are producing IPS panels with refresh rates of 240 Hz. For example, the 27-inch 1080p ASUS VG279QM uses an IPS panel and supports 280 Hz.
Previously, TNs exhibited less input lag than any other panel, but IPS technology has finally caught up. In June 2019, LG announced its new Nano IPS UltraGear monitors with a response time of one millisecond.
Despite the gap being closed, you’ll still pay more for an IPS panel with such a low response time than you would for a TN with similar specs. If you’re on a budget, expect a response time of around four milliseconds for a good IPS monitor.
One last thing to be aware of with IPS panels is a phenomenon called “IPS glow.” It’s when you see the display’s backlight shining through it at more extreme viewing angles. It’s not a huge problem unless you view the panel from the side, but it’s something to keep in mind.
VA panels are something of a compromise between TN and IPS. They offer the best contrast ratios, which is why TV manufacturers use them extensively. While an IPS monitor typically has a contrast ratio of 1000:1, it’s not unusual to see 3000:1 or 6000:1 in a comparable VA panel.
In terms of viewing angles, VAs can’t quite match the performance of IPS panels. Screen brightness, in particular, can vary based on the angle from which you’re viewing, but you won’t get the “IPS glow.”
VAs have slower response times than TNs and the newer Nano IPS panels with their one-millisecond response rates. You can find VA monitors with high refresh rates (240 Hz), but the latency can result in more ghosting and motion blur. For this reason, competitive gamers should avoid VA.
Compared to TNs, VA panels do offer much better color reproduction and typically hit the full sRGB spectrum, even on lower-end models. If you’re willing to spend a bit more, Samsung’s Quantum Dot SVA panels can hit 125 percent sRGB coverage.
For these reasons, VA panels are seen as the jack of all trades. They’re ideal for general use, but they either match or fall short in most other areas except contrast ratio. VAs are good for gamers who enjoy single-player or casual experiences.
When compared to CRT monitors, all LCD panels suffer from some form of latency issue. This was a real problem when TN panels first appeared, and it’s plagued IPS and VA monitors for years. But technology has moved on, and while many of these issues have been improved, they haven’t been eliminated entirely.
Uneven backlighting is another issue you’ll find on all panel types. Often this comes down to overall build quality—cheaper models slack on quality control to save on production costs. So, if you’re looking for a cheap monitor, be prepared for some uneven backlighting. However, you’ll mostly only notice it on solid or very dark backgrounds.
LCD panels are also susceptible to dead or stuck pixels. Different manufacturers and jurisdictions have different policies and consumer laws covering dead pixels. If you’re a perfectionist, check the manufacturer’s dead-pixel policy before you buy. Some will replace a monitor with a single dead pixel for free, while others require a minimum number.
Office or study use: Your budget should be your primary concern here. VA is the do-it-all panel, with superior viewing angles to TN, but either would do the trick. You can save some money because you don’t need high refresh rates or ultra-low latency. They’re still nice, though. You’ll see a noticeable difference in smoothness just when moving the Windows cursor on a monitor with a 144 versus 60 Hz refresh rate.
Photo and video editors/Digital artists: IPS panels are still generally favored for their ability to display a wide gamut of colors. It’s not unusual to find VA panels that also cover a wide gamut (125 percent sRGB, and over 90 percent DCI-P3), but they tend to exhibit more motion blur during fast-paced action than IPS panels. If you’re serious about color accuracy, you’ll need to properly calibrate your monitor.
Programmers who mount monitors vertically: You might think TN panels are great for programmers, but that’s not necessarily the case. TN panels have particularly bad viewing angles on the vertical axis. If you mount your monitor in portrait mode (as many programmers and mobile developers do), you’ll get the worst possible viewing angles from a TN panel. For the best possible viewing angles in this scenario, invest in an IPS display.
Competitive online gamers: There’s no question TN panels are still favored in the eSports world. Even the cheapest models have fast response times and support for high refresh rates. For 1080p gaming, a 24-inch will do just fine, or you could opt for a 1440p, 27-inch model without breaking the bank. You might want to go for an IPS panel as more low-latency models hit the market, but expect to pay more.
Non-competitive, high-end PC gamers: For a rich, immersive image that pops, a VA panel will provide a higher contrast ratio than IPS or TN. For deep blacks and a sharp, contrasting image, VA is the winner. If you’re okay with sacrificing some contrast, you can go the IPS route. However, we’d recommend avoiding TN altogether unless you play competitively.
Best all-rounder: VA is the winner here, but IPS is better in all areas except contrast ratio. If you can sacrifice contrast, an IPS panel will provide fairly low latency, decent blacks, and satisfactory color coverage.
So, why is this important? A monitor’s panel technology is important because it affects what the monitor can do and for which uses it is best suited. Each of the monitor panel types listed above offer their own distinctive benefits and drawbacks.
Choosing which type of monitor panel type to buy will depend largely on your intended usage and personal preference. After all, gamers, graphic designers, and office workers all have different requirements. Specific types of displays are best suited for different usage scenarios.
The reason for this is because none of the different monitor panel types as they are today can be classified as “outstanding” for all of the attributes mentioned above.
Below we’ll take a look at how IPS, TN, and VA monitors affect screen performance and do some handy summaries of strengths, weaknesses, and best-case uses for each type of panel technology.
IPS monitors or “In-Plane Switching” monitors, leverage liquid crystals aligned in parallel to produce rich colors. IPS panels are defined by the shifting patterns of their liquid crystals. These monitors were designed to overcome the limitations of TN panels. The liquid crystal’s ability to shift horizontally creates better viewing angles.
IPS monitor variations include S-IPS, H-IPS, e-IPS and P-IPS, and PLS (Plane-to-Line Switching), the latter being the latest iteration. Since these variations are all quite similar, they are all collectively referred to as “IPS-type” panels. They all claim to deliver the major benefits associated with IPS monitors – great color and ultra-wide viewing angles.
With regard to gaming, some criticisms IPS monitors include more visible motion blur coming as a result of slower response times, however the impact of motion blur will vary from user to user. In fact, mixed opinions about the “drawbacks” of IPS monitor for gaming can be found all across the web. Take this excerpt from one gaming technology writer for example: “As for pixel response, opinions vary. I personally think IPS panels are quick enough for almost all gaming. If your gaming life is absolutely and exclusively about hair-trigger shooters, OK, you’ll want the fastest response, lowest latency LCD monitor. And that means TN. For the rest of us, and certainly for those who place even a modicum of importance on the visual spectacle of games, I reckon IPS is clearly the best panel technology.” Read the full article here.
IPS monitors deliver ultra-wide 178-degree vertical and horizontal viewing angles. Graphic designers, CAD engineers, pro photographers, and video editors will benefit from using an IPS monitor. Many value the color benefits of IPS monitors and tech advances have improved IPS panel speed, contrast, and resolution. IPS monitors are more attractive than ever for general desktop work as well as many types of gaming. They’re even versatile enough to be used in different monitor styles, so if you’ve ever compared an ultrawide vs. dual monitor setup or considered the benefits of curved vs. flat monitors, chances are you’ve already come into contact with an IPS panel.
TN monitors, or “Twisted Nematic” monitors, are the oldest LCD panel types around. TN panels cost less than their IPS and VA counterparts and are a popular mainstream display technology for desktop and laptop displays.
Despite their lower perceived value, TN-based displays are the panel type preferred by competitive gamers. The reason for this is because TN panels can achieve a rapid response time and the fastest refresh rates on the market (like this 240Hz eSports monitor). To this effect, TN monitors are able to reduce blurring and screen tearing in fast-paced games when compared to an IPS or VA panel.
On the flip side, however, TN panel technology tends to be ill-suited for applications that benefit from wider viewing angles, higher contrast ratios, and better color accuracy. That being said, LED technology has helped shift the perspective and today’s LED-backlit TN models offer higher brightness along with better blacks and higher contrast ratios.
The greatest constraint of TN panel technology, however, is a narrower viewing angle as TN monitors experience more color shifting than other types of panels when being viewed at an angle.
Today’s maximum possible viewing angles are 178 degrees both horizontally and vertically (178º/178º), yet TN panels are limited to viewing angles of approximately 170 degrees horizontal and 160 degrees vertical (170º /160º).
TN monitors are the least expensive panel technology, making them ideal for cost-conscious businesses and consumers. In addition, TN monitors enjoy unmatched popularity with competitive gamers and other users who seek rapid graphics display.
Vertical alignment (VA) panel technology was developed to improve upon the drawbacks of TN. Current VA-based monitors offer muchhigher contrast, better color reproduction, and wider viewing angles than TN panels. Variations you may see include P-MVA, S-MVA, and AMVA (Advanced MVA).
These high-end VA-type monitors rival IPS monitors as the best panel technology for professional-level color-critical applications. One of the standout features of VA technology is that it is particularly good at blocking light from the backlight when it’s not needed. This enables VA panels to display deeper blacks and static contrast ratios of up to several times higher than the other LCD technologies. The benefit of this is that VA monitors with high contrast ratios can deliver intense blacks and richer colors.
These monitors also provide more visible details in shadows and highlights, making them ideal for enjoying videos and movies. They’re also a good fit for games focused on rich imagery (RPG games for example) rather than rapid speed (such as FPS games).
MVA and other recent VA technologies offer the highest static contrast ratios of any panel technology. This allows for an outstanding visual experience for movie enthusiasts and other users seeking depth of detail. Higher-end, feature-rich MVA displays offer the consistent, authentic color representation needed by graphic designers and other pro users.
There is another type of panel technology that differs from the monitor types discussed above and that is OLED or “Organic Light Emitting Diode” technology. OLEDs differ from LCDs because they use positively/negatively charged ions to light up every pixel individually, while LCDs use a backlight, which can create an unwanted glow. OLEDs avoid screen glow (and create darker blacks) by not using a backlight. One of the drawbacks of OLED technology is that it is usually pricier than any of the other types of technology explained.
When it comes to choosing the right LCD panel technology, there is no single right answer. Each of the three primary technologies offers distinct strengths and weaknesses. Looking at different features and specs helps you identify which monitor best fits your needs.
LCD or “Liquid Crystal Display” is a type of monitor panel that embraces thin layers of liquid crystals sandwiched between two layers of filters and electrodes.
While CRT monitors used to fire electrons against glass surfaces, LCD monitors operate using backlights and liquid crystals. The LCD panel is a flat sheet of material that contains layers of filters, glass, electrodes, liquid crystals, and a backlight. Polarized light (meaning only half of it shines through) is directed towards a rectangular grid of liquid crystals and beamed through.
Note: When searching for monitors you can be sure to come across the term “LED Panel” at some point or another. An LED panel is an LCD screen with an LED – (Light Emitting Diode) – backlight. LEDs provide a brighter light source while using much less energy. They also have the ability to produce white color, in addition to traditional RGB color, and are the panel type used in HDR monitors.
Early LCD panels used passive-matrix technology and were criticized for blurry imagery. The reason for this is because quick image changes require liquid crystals to change phase quickly and passive matrix technology was limited in terms of how quickly liquid crystals could change phase.
Thanks to active-matrix technology, LCD monitor panels were able to change images very quickly and the technology began being used by newer LCD panels.
Ultimately, budget and feature preferences will determine the best fit for each user. Among the available monitors of each panel type there will also be a range of price points and feature sets. Additionally, overall quality may vary among manufacturers due to factors related to a display’s components, manufacturing, and design.
Alternatively, if you’re into gaming and are in the market for TN panel these gaming monitor options may be along the lines of what you’re looking for.
TN stands for twisted nematic. This is a type of LED (a form of LCD) panel display technology. TN panels are characterized as being the fastest and cheapest among the other main types of display panels, VA (vertical alignment)and IPS (in-plane switching). As such, they work great for gaming monitors and gaming laptops. However, TN panels also offer the worst viewing angles and color when compared to VA and IPS panels.
DisplayWorst viewing angles;Worst colorViewing angles typically better than TN, worse than IPS; Good color; Best contrast;Best image depthBest viewing angles; Best color
VA stands for vertical alignment and is a a type of LED (a form of LCD)panel display technology. VA panels are characterized as having the best contrast and image depth among the other main types of display panels, ), but also the longest response times. As such, you may want to think twice before choosing a VA panel as a gaming monitor. However, we regard contrast as the most important factor in a monitor"s image quality. So if you’re looking for the best possible picture, we highly recommend a VA display.
When buying a PC monitor or even a gaming laptop, you may see displays listed as “SVA” instead of “VA”. SVA stands for “super vertical alignment” and is a term created by Samsung. Long story short, SVA is a type of VA panel that claims to bring better viewing angles, which is why some people will say SVA stands for “super viewing angles.” Either way, SVA means better image quality when viewing the screen from the side, above, below or in very sunny or bright atmospheres.
According to Samsung, SVA panels achieve better viewing angles by laying its liquid crystals into varying directions, allowing viewers to see the same color no matter their viewing angle. “With shaping liquid crystal cell structure as a boomerang, further dividing each sub-pixel into two different sections that are oppositely aligned (also referred to as fish-bone structure), viewing angles are no longer an issue,” Samsung says. However, an IPS display will likely still offer better viewing angles than an SVA display.
DisplayWorst viewing angles;Worst colorViewing angles typically better than TN, worse than IPS; Good color; Best contrast;Best image depthBest viewing angles; Best color
LCD Monitor Course II, which kicks off this session, will address certain points one must know to choose the LCD monitor best-suited to one"s needs from the various models available. Part 1 will focus on color gamut. While wide color gamuts are the latest trend in LCD monitors, color gamut is a term that lends itself to misunderstanding. Our hope is that this session will help users better understand the color gamut of LCD monitors and better select, use, and adjust the products.
Note: Below is the translation from the Japanese of the ITmedia article "IT Media LCD Monitor Course II, Part 1" published on November 11, 2008. Copyright 2011 ITmedia Inc. All Rights Reserved.
Various standards govern color gamuts. The three standards frequently cited in relation to personal computers are sRGB, Adobe RGB, and NTSC. The color gamut defined by each standard is depicted as a triangle on the xy chromaticity diagram. These triangles show the peak RGB coordinates connected by straight lines. A larger area inside a triangle is regarded to represent a standard capable of displaying more colors. For LCD monitors, this means that a product compatible with a color gamut associated with a larger triangle can reproduce a wider range of colors on screen.
This is a CIE XYZ color system xy chromaticity diagram. The areas enclosed in dotted lines represent the range of colors human beings can see with the naked eye. The ranges corresponding to the sRGB, Adobe RGB, and NTSC standards defining color gamuts appear as triangles connecting their RGB peak coordinates. The color gamut of an LCD monitor"s hardware can be indicated using similar triangles. An LCD monitor is not capable of reproduction (display) of colors outside its color gamut.
The standard color gamut for personal computers is the international sRGB standard prepared in 1998 by the International Electrotechnical Commission (IEC). sRGB has established a firm position as the standard in Windows environments. In most cases, products like LCD monitors, printers, digital cameras, and various applications are configured to reproduce the sRGB color gamut as accurately as possible. By ensuring that the devices and applications used in the input and output of image data are sRGB compatible, we can reduce discrepancies in color between input and output.
Adobe RGB was defined in 1998 by Adobe Systems, maker of the well-known Photoshop series of photo-retouching software products. While not an international standard like sRGB, it has become— backed by the high market share of Adobe"s graphics applications—the de facto standard in professional color imaging environments and in the print and publishing industries. Growing numbers of LCD monitors can reproduce most of the Adobe RGB color gamut.
NTSC, the color-gamut standard for analog television, is a color gamut developed by the National Television Standards Committee of the United States. While the range of colors that can be depicted under the NTSC standard is close to that of Adobe RGB, its R and B values differ slightly. The sRGB color gamut covers about 72% of the NTSC gamut. While monitors capable of reproducing the NTSC color gamut are required in places like video production sites, this is less important for individual users or for applications involving still images. sRGB compatibility and the capacity to reproduce the Adobe RGB color gamut are key points of LCD monitors that handle still images.
In general, the LCD monitors currently available for use with PCs have color gamuts capable of displaying nearly the entire sRGB gamut, thanks to the specifications for their LCD panels (and panel controls). However, given the rising demand mentioned above for reproducing color gamuts broader than sRGB, recent models have expanded the color gamuts of LCD monitors, with Adobe RGB serving as one target. But how is such expansion of LCD monitor color gamuts taking place?
Improvements in backlights account for a significant proportion of the technologies expanding the color gamuts of LCD monitors. There are two major approaches to doing this: one involves expanding the color gamut of cold cathodes, the mainstream backlight technology; the other involves RGB LED backlights.
On the subject of color-gamut expansion using cold cathodes, while strengthening the LCD panel"s color filter is a quick fix, this also lowers screen luminance by decreasing light transmissivity. Increasing the luminance of the cold cathode to counter this effect tends to shorten the life of the device and often results in lighting irregularities. Efforts to date have overcome these drawbacks to a large extent; many LCD monitors feature cold cathodes with wide color gamuts resulting from modification of their phosphors. This generates cost benefits as well, since it makes it possible to expand the color gamut without major changes in the existing structure.
Use of RGB LED backlights has increased relatively recently. These backlights make it possible to achieve higher levels of luminance and purity of color than cold cathodes. Despite certain disadvantages, including lower color stability (i.e., radiant-heat problems) than a cold cathode and difficulty in attaining a uniform white color across the entire screen, since it involves a mixture of RGB LEDs, these weaknesses have been resolved for the most part. RGB LED backlights cost more than cold-cathode backlights and are currently used in a fairly small proportion of LCD monitors. However, based on their efficacy in expanding color gamuts, the number of LCD monitors incorporating the technology will likely increase. This is also true for LCD televisions.
In passing, many LCD monitors that extol wide color gamuts promote the area ratios of specific color gamuts (i.e., triangles on the xy chromaticity diagram). Many of us have probably have seen indications of attributes such as Adobe RGB rates and NTSC rates in product catalogs.
However, these are only area ratios. Very few products include the entire Adobe RGB and NTSC color gamuts. Even if a monitor featured a 120% Adobe RGB ratio, it would remain impossible to determine the extent of the difference in RGB values between the LCD monitor"s color gamut and the Adobe RGB color gamut. Since such statements lend themselves to misinterpretation, it is important to avoid being confused by product specifications.
To eliminate problems involving labeled specifications, some manufacturers use the expression "coverage" in place of "area." Clearly, for example, an LCD monitor labeled as having Adobe RGB coverage of 95% can reproduce 95% of the Adobe RGB color gamut.
From the user"s perspective, coverage is a more user-friendly, easier-to-understand type of labeling than surface ratio. While switching all labeling to coverage presents difficulties, showing in xy chromaticity diagrams the color gamuts of LCD monitors to be used in color management will certainly make it easier for users to form their own judgments.
With regard to the difference between area labeling and coverage labeling as gauges of an LCD monitor"s color gamut, to use Adobe RGB as an example, in many cases, even a monitor with an Adobe RGB ratio of 100% in terms of area will feature coverage of less than 100 percent. Since coverage impacts practical use, one must avoid the mistake of seeing a higher figure as automatically better.
When we check the color gamut of an LCD monitor, it"s also important to remember that a wide color gamut is not necessarily equivalent to high image quality. This point may generate misunderstanding among many people.
Color gamut is one spec used to measure the image quality of an LCD monitor, but color gamut alone does not determine image quality. The quality of the controls used to realize the full capabilities of an LCD panel having a wide color gamut is crucial. In essence, the capacity to generate accurate colors suited to one"s own purposes outweighs a wide color gamut.
When considering an LCD monitor with a wide color gamut, we need to determine if it has a color-gamut conversion function. Such functions control the LCD monitor"s color gamut based on the target color gamut, such as Adobe RGB or sRGB. For example, by selecting sRGB mode from a menu option, we can adjust even an LCD monitor with a wide color gamut and high Adobe RGB coverage so that the colors displayed on screen fall within the sRGB color gamut.
Few current LCD monitors offer color-gamut conversion functions (i.e., feature compatibility with both Adobe RGB and sRGB color gamuts). However, a color-gamut conversion function is essential for applications demanding accurate color generation in the Adobe RGB and sRGB color gamuts, such as photo retouching and Web production.
For purposes requiring accurate color generation, an LCD color monitor lacking any color-gamut conversion function but having a wide color gamut can actually be a disadvantage in some cases. These LCD monitors display each RGB color mapped to the color gamut inherent to the LCD panel in eight bits at full color. As a result, the colors generated are often too vivid for displaying images in the sRGB color gamut (i.e., the sRGB color gamut cannot be reproduced accurately).
Shown here are examples of an sRGB color gamut photograph displayed on an sRGB-compatible LCD monitor (photo at left) and on an LCD monitor with a wide color gamut but incompatible with sRGB and with no color-gamut conversion function (photo at right). While the photograph at right appears vivid, saturation is unnaturally high in parts of the photo. We also see a significant departure from the colors envisioned by the photographer, as well as so-called memory colors.
In more than a few cases, as expanding LCD monitor color gamuts result in the capacity to reproduce a wider range of colors and more opportunities to check colors or adjusting images on monitor screens, problems such as breakdowns in tonal gradations, variations in chromaticity caused by narrow viewing angles, and screen display irregularities, less conspicuous at color gamuts in the sRGB range, have become more pronounced. As mentioned earlier, the mere fact of incorporating an LCD panel with a wide color gamut does not ensure that an LCD monitor offers high image quality. On this subject, let"s take a close look at various technologies for putting a wide color gamut to use.
First we look at technologies to increase gradation. Key here is the internal gamma-correction function for multi-level gradation. This function displays eight-bit input signals on screen in each RGB color from the PC side after first subjecting them to multi-level gradation to 10 or more bits in each RGB color inside the LCD monitor, then assigning these to each RGB eight-bit color deemed optimal. This improves tonal gradations and gaps in hue by improving the gamma curve.
On the subject of the viewing angle of an LCD panel, while larger screen sizes generally make it easier to see differences, particularly with products with wide color gamuts, variations in chromaticity can be an issue. For the most part, chromaticity variation due to viewing angle is determined by the technology of the LCD panel, with superior ones showing no variation in color even when viewed from a moderate angle. Setting aside the various particulars of LCD panel technologies, these generally include in-plane switching (IPS), vertical alignment (VA), and twisted nematic (TN) panels, listed from smaller to larger chromaticity variation. While TN technology has advanced to the point at which viewing angle characteristics are much improved from several years back, a significant gap remains between this technology and VA and IPS technologies. If color performance and chromaticity variation are important, VA or IPS technology remains the better choice.
A uniformity-correction function is a technology for reducing display irregularities. The uniformity referred to here refers to colors and brightness (luminance) on screen. An LCD monitor with superior uniformity has low levels of screen luminance irregularities or color irregularities. High-performance LCD monitors feature systems that measure luminance and chromaticity at each position on screen and correct them internally.
This is a comparison of monitors with and without uniformity correction. An LCD monitor with uniformity correction (photo at left) has more uniform luminance and color on screen than one lacking uniformity correction (photo at right). The two photographs above have been adjusted to equalize levels to emphasize display irregularities. Actual irregularities would be less conspicuous.
To make full use of an LCD monitor with a wide color gamut and to display colors as the user intended, one needs to consider adopting a calibration environment. LCD monitor calibration is a system for measuring colors on screen using a special-purpose calibrator and reflecting the characteristics of the colors in the ICC profile (a file defining device color characteristics) used by the operating system. Going through an ICC profile ensures uniformity between the color information handled by graphics software or other software and the colors generated by the LCD monitor to a high degree of precision.
Software calibration refers to following the instructions of specialized calibration software to adjust parameters such as luminance, contrast, and color temperature (RGB balance) using the LCD monitor"s adjustment menu, approaching the intended color through manual adjustments. Graphics driver colors are manipulated in some cases in place of the LCD monitor"s adjustment menu. Software calibration features low cost and can be used to calibrate any LCD monitor.
In contrast, hardware calibration is clearly more precise than software calibration. It also requires less effort, although it can be used only with compatible LCD monitors and entails certain setup costs. In general, it involves the following steps: calibration software controls the calibrator; matching color characteristics on screen with target color characteristics and directly adjusting the LCD monitor"s luminance, contrast, and gamma-correction table (look-up table) at the hardware level. Another aspect of hardware calibration that cannot be overlooked is its ease of use. All tasks through the preparation of an ICC profile for the results of adjustment and registering this to the OS are done automatically.
The EIZO LCD monitors currently compatible with hardware calibration include models in the ColorEdge series. The FlexScan series uses software calibration. (Note: As of January 2011, FlexScan monitors compatible with EasyPIX ver. 2 offer hardware calibration functionality.)
In the next session, we will examine LCD monitor interfaces and a number of video interfaces for LCD monitors, including the latest generation of interfaces such as HDMI and DisplayPort.