phones with ips lcd display free sample

Market forces made us endure screens interrupted with various sorts of notches and cutouts for a considerable time, but that’s all about to end soon. In the last few years, we have seen the Android community evolve from hating notches to being indifferent towards them. But living with the new wave of bezel-less, full-view display phones has convinced us that the world is better off without notches and it’s imperative that natural order be restored to our phone screens. (हिंदी में पढ़िए)
For now, most of the true full-view and notch-less display phones use Pop-up cameras or sliders, but a few tech giants including Samsung, Oppo, and Xiaomi have already demonstrated prototypes or released phones that place the front camera behind the screen.
Samsung Galaxy Z Fold 4 5G comes with an improved under-display camera (UDC) which was first introduced in 2021. The main screen of this foldable phone is a 7.6-inch Dynamic AMOLED 2X panel with a 22.5:18 aspect ratio, QXGA+ (2208 x 1768) resolution, 120Hz refresh rate, and 374ppi. Thanks to that UDC, you get an 90.9% screen-to-body ratio.
In our review of the device, we found the UDC to be discreet most of the time and is only evident in certain colored backgrounds and when you view it from an off-axis. However, it is definitely an engineering marvel and cool from a visual standpoint. Also, on the front, there is a 6.2-inch 120Hz FHD+ cover screen with a narrow aspect ratio.
Rest, the device runs on a Snapdragon 8+ gen 1 chipset, 12GB LPDDR5 RAM, 256/512GB UFS 3.1 storage, 4400mAh with 25W fast charging, and a penta-camera setup.
Xiaomi’s Mi Mix 4 is yet another under-screen camera phone. It calls its implementation CUP (Camera Under Panel), but the mechanism is pretty much the same as the other under-display selfie cameras out there. Above its 20MP selfie camera lies 400ppi pixels of the screen. This display stretches 6.67 inches and sports 120Hz refresh rate.
It ships with Snapdragon 888+ processor, 8GB/12GB RAM, 128GB/512GB storage, 4,500mAh battery and has 120W wired charging, 108MP camera, and Harman/Kardon speakers.
Asus Zenfone 8 Flip has a 6.67-inch (2400 × 1080 pixels) Full HD+ E4 AMOLED HDR10+ display with 90Hz refresh rate, 200Hz touch sampling rate, 110% DCI-P3 color coverage, up to 1000 nits brightness, and Corning Gorilla Glass 6 protection. This full screen fascia is possible thanks to a flip camera module.
Legion Duel 2 is a gaming smartphone from Lenovo that’s envisioned to be used in landscape orientation primarily. The screen is a 6.92-inch Full HD+ AMOLED panel with 144Hz refresh rate, 1300 nits peak brightness, 111.1% DCI-P3 color gamut support, and 20.5:9 aspect ratio.
The front camera is present within a pop-up camera that raises from the right-hand edge of the phone. The logic is to allow players to stream their gameplay while playing in the horizontal orientation.
OnePlus was one of the first few Android OEMs to usher in a notch, and it’s also one of the first in the premium segment to get rid with OnePlus 7 Pro (review). It further continued the trend with OnePlus 7T Pro which comes with a gorgeous true full-view display with extremely narrow bezels.
The 90Hz refresh rate makes it super smooth, the resolution goes all the way up to 2K, and, there are those slick curves at the edges. The phone is powered by Snapdragon 855 octa-core chipset paired with high-quality UFS 3.1 storage and LPDDR4X RAM. On the downside, the 7 Pro is big and bulky, is missing the audio jack, and has a mediocre set of cameras.
The elevating module opens like a fin and also makes room for the earpiece and LED flash. Anyway, the result is an immersive full-view AMOLED display that extends edge to edge. The Reno 10X Zoom has flagship-grade specs, including the Snapdragon 855, but all the tech housed within makes it a tad thick and heavy.
The Galaxy A80 is the only phone from Samsung with an AMOLED screen that extends edge to edge. Yes, even the high-end S-series and Note-series flagships rely on cutouts or punch holes to accommodate the front camera.
The 6Z (globally known as the Zenfone 6) is one of the most impressive phones we have seen from Asus in India. The 6Z (review) has a gorgeous and well-calibrated IPS LCD display that covers the entire facia. The selfie camera is housed in a flip module and this glass body phone houses a massive 5000mAh battery while being reasonably manageable.
The 6.4-inch screen has Full HD resolution which is quite sharp considering this is an IPS LCD and not AMOLED screen. This competitively priced Snapdragon 855-powered phone also has stereo speakers, 48MP primary camera, and runs an extremely close-to-stock version of Zen UI.
Xiaomi’s Redmi K20 Pro (review) brandishes an impressive set of specs that you’d otherwise find on phones priced significantly higher. With the K20 Pro, Xiaomi pays due attention to design and the phone gets a full-view AMOLED display (6.4-inch, full HD+) with an in-display fingerprint sensor lying underneath.
As is the case with most other Xiaomi phones, the K20 Pro is a great value proposition. Key features include triple rear cameras, 4000mAh battery with fast charging support, and MIUI 10 interface with fewer ads.
Oppo Reno, which is a trimmed-down version of the Oppo Reno 10X Zoom, has the same design with shark-fin pop-up and is also slimmer and significantly lighter. The handset has a 6.4-inch AMOLED display (Full HD) with around 87% screen-to-body ratio that targets DCI-P3 color gamut and is shielded by Gorilla Glass variant.
This one is missing 10X lossless zoom and Snapdragon 855, but the 48MP primary rear camera and SD 710 chipset should still be a good deal for light and moderate user.
Motorola One Fusion Plus rocks a 6.5-inch full HD+ notch-less TFT-LCD screen. It’s pop-up camera houses a 16MP sensor. Pivot and by the back you get a 64MP quartet.
The phone is powered by Snapdragon 730G with 6GB RAM, 128GB storage, and a 5000mAh battery. There is support for 15W fast charging. There is Vanilla Stock Android software too in the mix.
The Realme X (review) is a very competent phone that includes trendy features like a full-view AMOLED screen with minimal bezels on three sides, in-display fingerprint sensor, and pop-up camera – all for a sub Rs. 20,000 price.
The handset also comes in catchy onion and garlic gradients that look extremely premium. Other highlights include VOOC 3.0 fast charging, 48MP rear camera, and Snapdragon 710 chipset.
Redmi K20 passes on most of what’s good with the Redmi K20 Pro at a lower price point. The handset has the same design as the Pro variant and the same immersive full-view AMOLED display.
The Redmi K20 is however driven by Snapdragon 730 and replaces the Sony 48MP sensor with a Samsung sensor of the same resolution. Other features include in-display fingerprint reader, Pop-up camera, and 4000mAh battery with fast charging.
The Vivo 15 Pro has been around for a while, but it’s still a relevant option, especially at the new price. Both the V15 Pro and V15 employ a pop-up front camera and have a full-view display. The Pro variant, however, benefits from a better AMOLED screen and is powered by Snapdragon 675.
The Oppo K3 has a near bezel-less and uninterrupted AMOLED screen that measures 6.5-inch diagonally. The handset houses a 3765mAh battery with VOOC 3.0 fast charging support and runs Android Pie based Color OS.
Huawei Y9 Prime is the first Huawei phone in India to deliver a full-view screen. The IPS LCD display on the phone measures 6.59-inch and is full HD sharp.
The handset is powered by Kirin 710 octa-core chipset paired with 4GB RAM and 128GB storage. Other features include triple rear cameras, 4000mAh battery, and Android Pie based EMUI 10 software.
Samsung has developed one of the best full-view display devices globally. One such example of the same is the Samsung Galaxy Note 20 Ultra. The smartphone has a 6.9-inch dynamic AMOLED display complemented with a 120HZ refresh rate. The device has 12GB RAM and 256GB internal storage that can be expanded up to 1TB via a microSD card. It is powered by Samsung’s own Exynos 9 series processor.
On the camera front, the smartphone has a triple rear camera setup consisting of a 108MP primary shooter and two 12MP shooters. On the front, it gets a 10MP sensor for the sake of selfies and video calls. The device packs a 4500mAh battery along with fast charging as well as wireless charging support.
iQOO took the whole market by storm with the launch of the iQOO 9 Pro 5G. The smartphone stands as a strong competitor of devices like the OnePlus 9 Pro in the market. It comes with a 6.78-inch AMOLED display that also has a 120Hz refresh rate to offer a smoother experience. The smartphone runs on the Qualcomm Snapdragon 8 Gen 1 processor paired with 12GB RAM and 256GB internal storage in the high-end variant of the device.
The Xiaomi 12 Pro could be hailed as one of the best devices launched by the company so far. The smartphone has a 6.73-inch AMOLED display with a 120Hz refresh rate The smartphone works on the Qualcomm Snapdragon 8 Gen 1 processor for high-speed performance, It also has 8GB RAM and 256GB internal storage to store all your data.
The flagship devices by Vivo have always amazed the users in terms of camera prowess, performance, and display capabilities. Vivo X70 Pro follows the same trend with its 6.56-inch AMOLED display coupled with a 120Hz refresh rate. Though we will say that the smartphone lags behind in terms of the processor as it has a MediaTek Dimensity 1200 processor. Apart from that, it has 8GB RAM and 128GB internal storage that cannot be expanded.
The smartphone rocks a quad rear camera setup consisting of a 50MP primary sensor, two 12MP sensors, and an 8MP sensor for delivering the best shots in both daylight and low light. On the front, the device has a 32MP front camera for clicking selfies and attending video calls. The handset is powered by a 4450mAh battery that comes with flash charging support.
The OnePlus 10 series failed to make an impact like the OnePlus 9 series due to the changes and experiments. Still, the OnePlus 10 Pro was something which the audience loved because of the specs. The device works on the Qualcomm Snapdragon 8 Gen 1 processor with 12GB RAM and 256GB internal storage. The smartphone comes equipped with a Fluid AMOLED display and 120Hz refresh rate.
Furthermore, it flaunts a triple rear camera setup including a 48MP primary snapper, 50MP ultra wide-angle snapper, and an 8MP tertiary snapper. The smartphone has a 32MP camera at the front and it offers decent selfie shots along with allowing the user to attend video calls in HD. The device has a highly durable 5000mAh battery along with 80W superfast charging that completely charges the smartphone in less than 30 minutes.
The Samsung Galaxy S21 FE packs a compact 6.4-inch Dynamic AMOLED display along with a 120Hz refresh rate. The device runs on the Samsung Exynos 2100 processor accompanied by 8GB RAM and 128GB internal storage that is non-expandable in nature. The smartphone operates on the Android 12 operating system offering the user a snappy interface without lots of bloatware.
The Samsung Galaxy S21 FE features a triple rear camera setup consisting of a 12MP primary shooter, a 12MP secondary shooter, and an 8MP tertiary shooter. On the front, it has a 32MP camera for the sake for selfies and video calls. A 4500mAh battery powered the handset and it also comes with fast charging support.

What constitutes a great phone display? Is it the high resolution and pixel density? Well, that, and great screen quality test numbers, that"s why the Sony Xperia 1 IV specs with the 1644p 4K panel top our list. What about the high brightness and contrast that offer good outdoor visibility in the sun outdoors? That"s certainly important, but most of today"s flagships have HDR-certified panels that breach the 1000-nit barrier upwards to fit the standard, and their OLED tech ensures practically infinite contrast ratio, so it"s hard to pick on that merit alone.
Ditto for credible color gamut presentation, as per-unit display calibration is no longer a prerogative of Apple"s iPhones, while said HDR display flagships now cover both the standard RGB, and the wide P3 color gamut. Is it the actual white balance and DeltaE numbers then? It"s getting warmer, but throw in dynamically-adjusted refresh rate based on the content displayed, and you"ve narrowed it down to only a few choices when it comes to the best phone displays that we round up below.
Get the 512GB Galaxy S22 Ultra at up to $280 off with enhanced trade-in credit for a used Galaxy S21 Ultra also available, as is a $160 credit for a device with a cracked screen.
Not only does Sony make the only phones with 4K display resolution, but it also calibrates them to a near perfect level. The flagship Sony Xperia 1 IV carries a 6.5" 4K display with the whopping 643 PPI pixel density, and our display benchmarks returned class-beating brightness, white balance and wide gamut color representation credibility levels, some of the best we"ve measured. Add the high dynamic refresh rate, and the Sony Xperia 1 IV has probably the best panel on a phone so far.
The CIE 1931 xy color gamut chart represents the set (area) of colors that a display can reproduce, with the sRGB colorspace (the highlighted triangle) serving as reference. The chart also provides a visual representation of a display"s color accuracy. The small squares across the boundaries of the triangle are the reference points for the various colors, while the small dots are the actual measurements. Ideally, each dot should be positioned on top of its respective square. The "x: CIE31" and "y: CIE31" values in the table below the chart indicate the position of each measurement on the chart. "Y" shows the luminance (in nits) of each measured color, while "Target Y" is the desired luminance level for that color. Finally, "ΔE 2000" is the Delta E value of the measured color. Delta E values of below 2 are ideal.
The Color accuracy chart gives an idea of how close a display"s measured colors are to their referential values. The first line holds the measured (actual) colors, while the second line holds the reference (target) colors. The closer the actual colors are to the target ones, the better.
The Grayscale accuracy chart shows whether a display has a correct white balance (balance between red, green and blue) across different levels of grey (from dark to bright). The closer the Actual colors are to the Target ones, the better.
Pay attention to that "brightest" part and the 1Hz-120Hz specs at the full 1440p resolution. Yes, that means that the S22 Ultra is equipped with the newest LTPO OLED display technology that allowed for both the record 1750nits of peak brightness, 15% less battery consumption than what"s on the S21/S21+, and the dynamically-allocated refresh rate that can go down to 1Hz when you are looking at static images, or rev up all the way to 120Hz when you scroll.
This brightness is what makes the S22 Ultra display, in particular, stand out, as the granularly adaptive refresh rate has been on Oppo and OnePlus phones before it.
If you are looking for the best foldable phone display, it"s again Oppo that delivers with its Find N line, rather than Samsung. We tested the Find N2"s display to be one of the most color-credible panel among all phones, not only bendy ones, and the brightest on a foldable phone.
The CIE 1931 xy color gamut chart represents the set (area) of colors that a display can reproduce, with the sRGB colorspace (the highlighted triangle) serving as reference. The chart also provides a visual representation of a display"s color accuracy. The small squares across the boundaries of the triangle are the reference points for the various colors, while the small dots are the actual measurements. Ideally, each dot should be positioned on top of its respective square. The "x: CIE31" and "y: CIE31" values in the table below the chart indicate the position of each measurement on the chart. "Y" shows the luminance (in nits) of each measured color, while "Target Y" is the desired luminance level for that color. Finally, "ΔE 2000" is the Delta E value of the measured color. Delta E values of below 2 are ideal.
The Color accuracy chart gives an idea of how close a display"s measured colors are to their referential values. The first line holds the measured (actual) colors, while the second line holds the reference (target) colors. The closer the actual colors are to the target ones, the better.
The Grayscale accuracy chart shows whether a display has a correct white balance (balance between red, green and blue) across different levels of grey (from dark to bright). The closer the Actual colors are to the Target ones, the better.
As usual with Oppo, ever since its partnership with Pixelworks, there is a per-unit factory Delta E calibration, color-blindness presets, and camera-to-display wide color management system. The LTPO panel is factory-calibrated and delivers one of the best color credibility Delta measurements we"ve ever taken, with only Google"s Pixels being better here.
Moreover, the Find X5 Pro has the best white balance score, nearest to the 6500K reference point that means the screens colors are spot on in terms of warmth, neither too yellowish, nor cold and blueish. Adding the high typical or peak brightness levels, the company has managed to beat its own best phone displays record.
The CIE 1931 xy color gamut chart represents the set (area) of colors that a display can reproduce, with the sRGB colorspace (the highlighted triangle) serving as reference. The chart also provides a visual representation of a display"s color accuracy. The small squares across the boundaries of the triangle are the reference points for the various colors, while the small dots are the actual measurements. Ideally, each dot should be positioned on top of its respective square. The "x: CIE31" and "y: CIE31" values in the table below the chart indicate the position of each measurement on the chart. "Y" shows the luminance (in nits) of each measured color, while "Target Y" is the desired luminance level for that color. Finally, "ΔE 2000" is the Delta E value of the measured color. Delta E values of below 2 are ideal.
The Color accuracy chart gives an idea of how close a display"s measured colors are to their referential values. The first line holds the measured (actual) colors, while the second line holds the reference (target) colors. The closer the actual colors are to the target ones, the better.
The Grayscale accuracy chart shows whether a display has a correct white balance (balance between red, green and blue) across different levels of grey (from dark to bright). The closer the Actual colors are to the Target ones, the better.
To take full advantage of its excellent display panel"s abilities, the Find X5 Pro employs a "multi-brightness color calibration," meaning that the screen is as color-credible in all lighting conditions, be it on the beach or in the dark.
Google managed to catch up with factory calibration and its Pixel 6 Pro display now delivers not only one of the most feature-rich panels in the Android universe - 1440p resolution, dynamic 120Hz refresh rate, and high brightness, but it is also in the top three in terms of color representation in our display benchmark database.
Birds of a feather, the OnePlus 10 Pro and Oppo Find X5 Pro, as they sport the same 6.7" 1440p LTPO OLED panel with dynamic refresh rate and individual display calibration at the factory level courtesy of the imaging specialists from Pixelworks. Thus, you get a near-perfect color accuracy, wide gamut coverage, and high average brightness, all for less than $900 barring any running OnePlus 10 Pro deals.
The CIE 1931 xy color gamut chart represents the set (area) of colors that a display can reproduce, with the sRGB colorspace (the highlighted triangle) serving as reference. The chart also provides a visual representation of a display"s color accuracy. The small squares across the boundaries of the triangle are the reference points for the various colors, while the small dots are the actual measurements. Ideally, each dot should be positioned on top of its respective square. The "x: CIE31" and "y: CIE31" values in the table below the chart indicate the position of each measurement on the chart. "Y" shows the luminance (in nits) of each measured color, while "Target Y" is the desired luminance level for that color. Finally, "ΔE 2000" is the Delta E value of the measured color. Delta E values of below 2 are ideal.
The Color accuracy chart gives an idea of how close a display"s measured colors are to their referential values. The first line holds the measured (actual) colors, while the second line holds the reference (target) colors. The closer the actual colors are to the target ones, the better.
The Grayscale accuracy chart shows whether a display has a correct white balance (balance between red, green and blue) across different levels of grey (from dark to bright). The closer the Actual colors are to the Target ones, the better.
These measurements are made using Portrait Displays" CalMAN calibration software.The high dynamic refresh rate is the best thing that happened to mobile displays since the introduction of the OLED technology, and there is no looking back once you"ve tried it while browsing and scrolling. Here"s the answers on our question how does it all work exactly:
The display is also basically able to do what MEMC TVs do, automatically increasing frames in video to up the rate, and take better advantage of the high refresh rate even with content that is usually shot with 24fps or 30fps. Detailing the panel"s virtues in a blog post, the OnePlus CEO also mentioned that:
In order to reach industry-leading color accuracy standards, we have added an additional automatic color calibration machine to the production line. By adding an extra 30 seconds to the production time, each display panel is automatically calibrated for color accuracy before it’s released.
Apple"s finest finally found the 120Hz refresh feature (say that 3 times quickly) and if you are already invested in the iOS ecosystem, there is nothing better than the brightest, toughest displays on an iPhone so far, the one on the iPhone 14 Pro Max and iPhone 14 Pro.
Apple advertises it as having a record for a phone peak brightness level of 2000 nits, or more typical brightness of 1600 nits when consuming HDR content and 1000 nits otherwise. This is exactly what we measured and these displays are so advanced that only Samsung can make them at the moment with its 12th-gen OLED technology.
The CIE 1931 xy color gamut chart represents the set (area) of colors that a display can reproduce, with the sRGB colorspace (the highlighted triangle) serving as reference. The chart also provides a visual representation of a display"s color accuracy. The small squares across the boundaries of the triangle are the reference points for the various colors, while the small dots are the actual measurements. Ideally, each dot should be positioned on top of its respective square. The "x: CIE31" and "y: CIE31" values in the table below the chart indicate the position of each measurement on the chart. "Y" shows the luminance (in nits) of each measured color, while "Target Y" is the desired luminance level for that color. Finally, "ΔE 2000" is the Delta E value of the measured color. Delta E values of below 2 are ideal.
The Color accuracy chart gives an idea of how close a display"s measured colors are to their referential values. The first line holds the measured (actual) colors, while the second line holds the reference (target) colors. The closer the actual colors are to the target ones, the better.
The Grayscale accuracy chart shows whether a display has a correct white balance (balance between red, green and blue) across different levels of grey (from dark to bright). The closer the Actual colors are to the Target ones, the better.
Apple has partnered with its usual "made in America" investment suspects from Corning to master an exclusive mixture that it calls Ceramic Shield, hinting at the tough "glass-ceramic" material involved in the blend.
Say what you will about Google entering the fray here but the Pixels have very well calibrated displays and the new Pixel 6a is no exception. First off, its color credibility is better than the more established calibration champs here (just look at those DeltaE numbers below). It is also sufficiently bright, so if you are looking for a compact 5G Android phone with a great camera and display that won"t break the bank, the Pixel 6a would fit your narrative.
The CIE 1931 xy color gamut chart represents the set (area) of colors that a display can reproduce, with the sRGB colorspace (the highlighted triangle) serving as reference. The chart also provides a visual representation of a display"s color accuracy. The small squares across the boundaries of the triangle are the reference points for the various colors, while the small dots are the actual measurements. Ideally, each dot should be positioned on top of its respective square. The "x: CIE31" and "y: CIE31" values in the table below the chart indicate the position of each measurement on the chart. "Y" shows the luminance (in nits) of each measured color, while "Target Y" is the desired luminance level for that color. Finally, "ΔE 2000" is the Delta E value of the measured color. Delta E values of below 2 are ideal.
The Color accuracy chart gives an idea of how close a display"s measured colors are to their referential values. The first line holds the measured (actual) colors, while the second line holds the reference (target) colors. The closer the actual colors are to the target ones, the better.
The Grayscale accuracy chart shows whether a display has a correct white balance (balance between red, green and blue) across different levels of grey (from dark to bright). The closer the Actual colors are to the Target ones, the better.

In recent years OLED technology has emerged as the leading smartphone display technology, and the world"s most popular phone vendors are all shipping AMOLED smartphones.
In 2018, over 500 million AMOLED screens were produced - mostly to satisfy demand from mobile phones vendors. The smartphone OLED 2018 market was led by Samsung, whohas been using AMOLEDs in its high-end phones for many years, followed by Apple, LG, Xiaomi, Huawei and others. Samsung is branding its smartphone OLED displays as Super AMOLED display.
Most premium phones today adopt flexible OLED displays. Apple for example is using a flexible 5.8" 1125x2436 OLED (made by SDC) in its 2018 iPhone XS (the iPhone XS Max sports a larger 6.5" 1242x2688 flexible AMOLED). Display experts say that the iPhone XS Display is the world"s best smartphone display.
Most display experts and consumers agree that OLED displays are the world"s best smartphone displays. The best smartphone OLED displays are the Super AMOLED displays produced by Samsung Display, but other OLED producers (such as LG and BOE Display) are also producing high quality OLEDs.

Glass substrate with ITO electrodes. The shapes of these electrodes will determine the shapes that will appear when the LCD is switched ON. Vertical ridges etched on the surface are smooth.
A liquid-crystal display (LCD) is a flat-panel display or other electronically modulated optical device that uses the light-modulating properties of liquid crystals combined with polarizers. Liquid crystals do not emit light directlybacklight or reflector to produce images in color or monochrome.seven-segment displays, as in a digital clock, are all good examples of devices with these displays. They use the same basic technology, except that arbitrary images are made from a matrix of small pixels, while other displays have larger elements. LCDs can either be normally on (positive) or off (negative), depending on the polarizer arrangement. For example, a character positive LCD with a backlight will have black lettering on a background that is the color of the backlight, and a character negative LCD will have a black background with the letters being of the same color as the backlight. Optical filters are added to white on blue LCDs to give them their characteristic appearance.
LCDs are used in a wide range of applications, including LCD televisions, computer monitors, instrument panels, aircraft cockpit displays, and indoor and outdoor signage. Small LCD screens are common in LCD projectors and portable consumer devices such as digital cameras, watches, calculators, and mobile telephones, including smartphones. LCD screens have replaced heavy, bulky and less energy-efficient cathode-ray tube (CRT) displays in nearly all applications. The phosphors used in CRTs make them vulnerable to image burn-in when a static image is displayed on a screen for a long time, e.g., the table frame for an airline flight schedule on an indoor sign. LCDs do not have this weakness, but are still susceptible to image persistence.
Each pixel of an LCD typically consists of a layer of molecules aligned between two transparent electrodes, often made of Indium-Tin oxide (ITO) and two polarizing filters (parallel and perpendicular polarizers), the axes of transmission of which are (in most of the cases) perpendicular to each other. Without the liquid crystal between the polarizing filters, light passing through the first filter would be blocked by the second (crossed) polarizer. Before an electric field is applied, the orientation of the liquid-crystal molecules is determined by the alignment at the surfaces of electrodes. In a twisted nematic (TN) device, the surface alignment directions at the two electrodes are perpendicular to each other, and so the molecules arrange themselves in a helical structure, or twist. This induces the rotation of the polarization of the incident light, and the device appears gray. If the applied voltage is large enough, the liquid crystal molecules in the center of the layer are almost completely untwisted and the polarization of the incident light is not rotated as it passes through the liquid crystal layer. This light will then be mainly polarized perpendicular to the second filter, and thus be blocked and the pixel will appear black. By controlling the voltage applied across the liquid crystal layer in each pixel, light can be allowed to pass through in varying amounts thus constituting different levels of gray.
The chemical formula of the liquid crystals used in LCDs may vary. Formulas may be patented.Sharp Corporation. The patent that covered that specific mixture expired.
Most color LCD systems use the same technique, with color filters used to generate red, green, and blue subpixels. The LCD color filters are made with a photolithography process on large glass sheets that are later glued with other glass sheets containing a TFT array, spacers and liquid crystal, creating several color LCDs that are then cut from one another and laminated with polarizer sheets. Red, green, blue and black photoresists (resists) are used. All resists contain a finely ground powdered pigment, with particles being just 40 nanometers across. The black resist is the first to be applied; this will create a black grid (known in the industry as a black matrix) that will separate red, green and blue subpixels from one another, increasing contrast ratios and preventing light from leaking from one subpixel onto other surrounding subpixels.Super-twisted nematic LCD, where the variable twist between tighter-spaced plates causes a varying double refraction birefringence, thus changing the hue.
LCD in a Texas Instruments calculator with top polarizer removed from device and placed on top, such that the top and bottom polarizers are perpendicular. As a result, the colors are inverted.
The optical effect of a TN device in the voltage-on state is far less dependent on variations in the device thickness than that in the voltage-off state. Because of this, TN displays with low information content and no backlighting are usually operated between crossed polarizers such that they appear bright with no voltage (the eye is much more sensitive to variations in the dark state than the bright state). As most of 2010-era LCDs are used in television sets, monitors and smartphones, they have high-resolution matrix arrays of pixels to display arbitrary images using backlighting with a dark background. When no image is displayed, different arrangements are used. For this purpose, TN LCDs are operated between parallel polarizers, whereas IPS LCDs feature crossed polarizers. In many applications IPS LCDs have replaced TN LCDs, particularly in smartphones. Both the liquid crystal material and the alignment layer material contain ionic compounds. If an electric field of one particular polarity is applied for a long period of time, this ionic material is attracted to the surfaces and degrades the device performance. This is avoided either by applying an alternating current or by reversing the polarity of the electric field as the device is addressed (the response of the liquid crystal layer is identical, regardless of the polarity of the applied field).
Displays for a small number of individual digits or fixed symbols (as in digital watches and pocket calculators) can be implemented with independent electrodes for each segment.alphanumeric or variable graphics displays are usually implemented with pixels arranged as a matrix consisting of electrically connected rows on one side of the LC layer and columns on the other side, which makes it possible to address each pixel at the intersections. The general method of matrix addressing consists of sequentially addressing one side of the matrix, for example by selecting the rows one-by-one and applying the picture information on the other side at the columns row-by-row. For details on the various matrix addressing schemes see passive-matrix and active-matrix addressed LCDs.
LCDs are manufactured in cleanrooms borrowing techniques from semiconductor manufacturing and using large sheets of glass whose size has increased over time. Several displays are manufactured at the same time, and then cut from the sheet of glass, also known as the mother glass or LCD glass substrate. The increase in size allows more displays or larger displays to be made, just like with increasing wafer sizes in semiconductor manufacturing. The glass sizes are as follows:
Until Gen 8, manufacturers would not agree on a single mother glass size and as a result, different manufacturers would use slightly different glass sizes for the same generation. Some manufacturers have adopted Gen 8.6 mother glass sheets which are only slightly larger than Gen 8.5, allowing for more 50 and 58 inch LCDs to be made per mother glass, specially 58 inch LCDs, in which case 6 can be produced on a Gen 8.6 mother glass vs only 3 on a Gen 8.5 mother glass, significantly reducing waste.AGC Inc., Corning Inc., and Nippon Electric Glass.
The origins and the complex history of liquid-crystal displays from the perspective of an insider during the early days were described by Joseph A. Castellano in Liquid Gold: The Story of Liquid Crystal Displays and the Creation of an Industry.IEEE History Center.Peter J. Wild, can be found at the Engineering and Technology History Wiki.
In 1888,Friedrich Reinitzer (1858–1927) discovered the liquid crystalline nature of cholesterol extracted from carrots (that is, two melting points and generation of colors) and published his findings at a meeting of the Vienna Chemical Society on May 3, 1888 (F. Reinitzer: Beiträge zur Kenntniss des Cholesterins, Monatshefte für Chemie (Wien) 9, 421–441 (1888)).Otto Lehmann published his work "Flüssige Kristalle" (Liquid Crystals). In 1911, Charles Mauguin first experimented with liquid crystals confined between plates in thin layers.
In 1922, Georges Friedel described the structure and properties of liquid crystals and classified them in three types (nematics, smectics and cholesterics). In 1927, Vsevolod Frederiks devised the electrically switched light valve, called the Fréedericksz transition, the essential effect of all LCD technology. In 1936, the Marconi Wireless Telegraph company patented the first practical application of the technology, "The Liquid Crystal Light Valve". In 1962, the first major English language publication Molecular Structure and Properties of Liquid Crystals was published by Dr. George W. Gray.RCA found that liquid crystals had some interesting electro-optic characteristics and he realized an electro-optical effect by generating stripe-patterns in a thin layer of liquid crystal material by the application of a voltage. This effect is based on an electro-hydrodynamic instability forming what are now called "Williams domains" inside the liquid crystal.
In 1964, George H. Heilmeier, then working at the RCA laboratories on the effect discovered by Williams achieved the switching of colors by field-induced realignment of dichroic dyes in a homeotropically oriented liquid crystal. Practical problems with this new electro-optical effect made Heilmeier continue to work on scattering effects in liquid crystals and finally the achievement of the first operational liquid-crystal display based on what he called the George H. Heilmeier was inducted in the National Inventors Hall of FameIEEE Milestone.
In the late 1960s, pioneering work on liquid crystals was undertaken by the UK"s Royal Radar Establishment at Malvern, England. The team at RRE supported ongoing work by George William Gray and his team at the University of Hull who ultimately discovered the cyanobiphenyl liquid crystals, which had correct stability and temperature properties for application in LCDs.
The idea of a TFT-based liquid-crystal display (LCD) was conceived by Bernard Lechner of RCA Laboratories in 1968.dynamic scattering mode (DSM) LCD that used standard discrete MOSFETs.
On December 4, 1970, the twisted nematic field effect (TN) in liquid crystals was filed for patent by Hoffmann-LaRoche in Switzerland, (Swiss patent No. 532 261) with Wolfgang Helfrich and Martin Schadt (then working for the Central Research Laboratories) listed as inventors.Brown, Boveri & Cie, its joint venture partner at that time, which produced TN displays for wristwatches and other applications during the 1970s for the international markets including the Japanese electronics industry, which soon produced the first digital quartz wristwatches with TN-LCDs and numerous other products. James Fergason, while working with Sardari Arora and Alfred Saupe at Kent State University Liquid Crystal Institute, filed an identical patent in the United States on April 22, 1971.ILIXCO (now LXD Incorporated), produced LCDs based on the TN-effect, which soon superseded the poor-quality DSM types due to improvements of lower operating voltages and lower power consumption. Tetsuro Hama and Izuhiko Nishimura of Seiko received a US patent dated February 1971, for an electronic wristwatch incorporating a TN-LCD.
In 1972, the concept of the active-matrix thin-film transistor (TFT) liquid-crystal display panel was prototyped in the United States by T. Peter Brody"s team at Westinghouse, in Pittsburgh, Pennsylvania.Westinghouse Research Laboratories demonstrated the first thin-film-transistor liquid-crystal display (TFT LCD).high-resolution and high-quality electronic visual display devices use TFT-based active matrix displays.active-matrix liquid-crystal display (AM LCD) in 1974, and then Brody coined the term "active matrix" in 1975.
In 1972 North American Rockwell Microelectronics Corp introduced the use of DSM LCDs for calculators for marketing by Lloyds Electronics Inc, though these required an internal light source for illumination.Sharp Corporation followed with DSM LCDs for pocket-sized calculators in 1973Seiko and its first 6-digit TN-LCD quartz wristwatch, and Casio"s "Casiotron". Color LCDs based on Guest-Host interaction were invented by a team at RCA in 1968.TFT LCDs similar to the prototypes developed by a Westinghouse team in 1972 were patented in 1976 by a team at Sharp consisting of Fumiaki Funada, Masataka Matsuura, and Tomio Wada,
In 1983, researchers at Brown, Boveri & Cie (BBC) Research Center, Switzerland, invented the passive matrix-addressed LCDs. H. Amstutz et al. were listed as inventors in the corresponding patent applications filed in Switzerland on July 7, 1983, and October 28, 1983. Patents were granted in Switzerland CH 665491, Europe EP 0131216,
The first color LCD televisions were developed as handheld televisions in Japan. In 1980, Hattori Seiko"s R&D group began development on color LCD pocket televisions.Seiko Epson released the first LCD television, the Epson TV Watch, a wristwatch equipped with a small active-matrix LCD television.dot matrix TN-LCD in 1983.Citizen Watch,TFT LCD.computer monitors and LCD televisions.3LCD projection technology in the 1980s, and licensed it for use in projectors in 1988.compact, full-color LCD projector.
In 1990, under different titles, inventors conceived electro optical effects as alternatives to twisted nematic field effect LCDs (TN- and STN- LCDs). One approach was to use interdigital electrodes on one glass substrate only to produce an electric field essentially parallel to the glass substrates.Germany by Guenter Baur et al. and patented in various countries.Hitachi work out various practical details of the IPS technology to interconnect the thin-film transistor array as a matrix and to avoid undesirable stray fields in between pixels.
Hitachi also improved the viewing angle dependence further by optimizing the shape of the electrodes (Super IPS). NEC and Hitachi become early manufacturers of active-matrix addressed LCDs based on the IPS technology. This is a milestone for implementing large-screen LCDs having acceptable visual performance for flat-panel computer monitors and television screens. In 1996, Samsung developed the optical patterning technique that enables multi-domain LCD. Multi-domain and In Plane Switching subsequently remain the dominant LCD designs through 2006.South Korea and Taiwan,
In 2007 the image quality of LCD televisions surpassed the image quality of cathode-ray-tube-based (CRT) TVs.LCD TVs were projected to account 50% of the 200 million TVs to be shipped globally in 2006, according to Displaybank.Toshiba announced 2560 × 1600 pixels on a 6.1-inch (155 mm) LCD panel, suitable for use in a tablet computer,
In 2016, Panasonic developed IPS LCDs with a contrast ratio of 1,000,000:1, rivaling OLEDs. This technology was later put into mass production as dual layer, dual panel or LMCL (Light Modulating Cell Layer) LCDs. The technology uses 2 liquid crystal layers instead of one, and may be used along with a mini-LED backlight and quantum dot sheets.
Since LCDs produce no light of their own, they require external light to produce a visible image.backlight. Active-matrix LCDs are almost always backlit.Transflective LCDs combine the features of a backlit transmissive display and a reflective display.
CCFL: The LCD panel is lit either by two cold cathode fluorescent lamps placed at opposite edges of the display or an array of parallel CCFLs behind larger displays. A diffuser (made of PMMA acrylic plastic, also known as a wave or light guide/guiding plateinverter to convert whatever DC voltage the device uses (usually 5 or 12 V) to ≈1000 V needed to light a CCFL.
EL-WLED: The LCD panel is lit by a row of white LEDs placed at one or more edges of the screen. A light diffuser (light guide plate, LGP) is then used to spread the light evenly across the whole display, similarly to edge-lit CCFL LCD backlights. The diffuser is made out of either PMMA plastic or special glass, PMMA is used in most cases because it is rugged, while special glass is used when the thickness of the LCD is of primary concern, because it doesn"t expand as much when heated or exposed to moisture, which allows LCDs to be just 5mm thick. Quantum dots may be placed on top of the diffuser as a quantum dot enhancement film (QDEF, in which case they need a layer to be protected from heat and humidity) or on the color filter of the LCD, replacing the resists that are normally used.
WLED array: The LCD panel is lit by a full array of white LEDs placed behind a diffuser behind the panel. LCDs that use this implementation will usually have the ability to dim or completely turn off the LEDs in the dark areas of the image being displayed, effectively increasing the contrast ratio of the display. The precision with which this can be done will depend on the number of dimming zones of the display. The more dimming zones, the more precise the dimming, with less obvious blooming artifacts which are visible as dark grey patches surrounded by the unlit areas of the LCD. As of 2012, this design gets most of its use from upscale, larger-screen LCD televisions.
RGB-LED array: Similar to the WLED array, except the panel is lit by a full array of RGB LEDs. While displays lit with white LEDs usually have a poorer color gamut than CCFL lit displays, panels lit with RGB LEDs have very wide color gamuts. This implementation is most popular on professional graphics editing LCDs. As of 2012, LCDs in this category usually cost more than $1000. As of 2016 the cost of this category has drastically reduced and such LCD televisions obtained same price levels as the former 28" (71 cm) CRT based categories.
Monochrome LEDs: such as red, green, yellow or blue LEDs are used in the small passive monochrome LCDs typically used in clocks, watches and small appliances.
Mini-LED: Backlighting with Mini-LEDs can support over a thousand of Full-area Local Area Dimming (FLAD) zones. This allows deeper blacks and higher contrast ratio.
Today, most LCD screens are being designed with an LED backlight instead of the traditional CCFL backlight, while that backlight is dynamically controlled with the video information (dynamic backlight control). The combination with the dynamic backlight control, invented by Philips researchers Douglas Stanton, Martinus Stroomer and Adrianus de Vaan, simultaneously increases the dynamic range of the display system (also marketed as HDR, high dynamic range television or FLAD, full-area local area dimming).
The LCD backlight systems are made highly efficient by applying optical films such as prismatic structure (prism sheet) to gain the light into the desired viewer directions and reflective polarizing films that recycle the polarized light that was formerly absorbed by the first polarizer of the LCD (invented by Philips researchers Adrianus de Vaan and Paulus Schaareman),
A pink elastomeric connector mating an LCD panel to circuit board traces, shown next to a centimeter-scale ruler. The conductive and insulating layers in the black stripe are very small.
A standard television receiver screen, a modern LCD panel, has over six million pixels, and they are all individually powered by a wire network embedded in the screen. The fine wires, or pathways, form a grid with vertical wires across the whole screen on one side of the screen and horizontal wires across the whole screen on the other side of the screen. To this grid each pixel has a positive connection on one side and a negative connection on the other side. So the total amount of wires needed for a 1080p display is 3 x 1920 going vertically and 1080 going horizontally for a total of 6840 wires horizontally and vertically. That"s three for red, green and blue and 1920 columns of pixels for each color for a total of 5760 wires going vertically and 1080 rows of wires going horizontally. For a panel that is 28.8 inches (73 centimeters) wide, that means a wire density of 200 wires per inch along the horizontal edge.
The LCD panel is powered by LCD drivers that are carefully matched up with the edge of the LCD panel at the factory level. The drivers may be installed using several methods, the most common of which are COG (Chip-On-Glass) and TAB (Tape-automated bonding) These same principles apply also for smartphone screens that are much smaller than TV screens.anisotropic conductive film or, for lower densities, elastomeric connectors.
Monochrome and later color passive-matrix LCDs were standard in most early laptops (although a few used plasma displaysGame Boyactive-matrix became standard on all laptops. The commercially unsuccessful Macintosh Portable (released in 1989) was one of the first to use an active-matrix display (though still monochrome). Passive-matrix LCDs are still used in the 2010s for applications less demanding than laptop computers and TVs, such as inexpensive calculators. In particular, these are used on portable devices where less information content needs to be displayed, lowest power consumption (no backlight) and low cost are desired or readability in direct sunlight is needed.
A comparison between a blank passive-matrix display (top) and a blank active-matrix display (bottom). A passive-matrix display can be identified when the blank background is more grey in appearance than the crisper active-matrix display, fog appears on all edges of the screen, and while pictures appear to be fading on the screen.
Displays having a passive-matrix structure are employing Crosstalk between activated and non-activated pixels has to be handled properly by keeping the RMS voltage of non-activated pixels below the threshold voltage as discovered by Peter J. Wild in 1972,
STN LCDs have to be continuously refreshed by alternating pulsed voltages of one polarity during one frame and pulses of opposite polarity during the next frame. Individual pixels are addressed by the corresponding row and column circuits. This type of display is called response times and poor contrast are typical of passive-matrix addressed LCDs with too many pixels and driven according to the "Alt & Pleshko" drive scheme. Welzen and de Vaan also invented a non RMS drive scheme enabling to drive STN displays with video rates and enabling to show smooth moving video images on an STN display.
Bistable LCDs do not require continuous refreshing. Rewriting is only required for picture information changes. In 1984 HA van Sprang and AJSM de Vaan invented an STN type display that could be operated in a bistable mode, enabling extremely high resolution images up to 4000 lines or more using only low voltages.
High-resolution color displays, such as modern LCD computer monitors and televisions, use an active-matrix structure. A matrix of thin-film transistors (TFTs) is added to the electrodes in contact with the LC layer. Each pixel has its own dedicated transistor, allowing each column line to access one pixel. When a row line is selected, all of the column lines are connected to a row of pixels and voltages corresponding to the picture information are driven onto all of the column lines. The row line is then deactivated and the next row line is selected. All of the row lines are selected in sequence during a refresh operation. Active-matrix addressed displays look brighter and sharper than passive-matrix addressed displays of the same size, and generally have quicker response times, producing much better images. Sharp produces bistable reflective LCDs with a 1-bit SRAM cell per pixel that only requires small amounts of power to maintain an image.
Segment LCDs can also have color by using Field Sequential Color (FSC LCD). This kind of displays have a high speed passive segment LCD panel with an RGB backlight. The backlight quickly changes color, making it appear white to the naked eye. The LCD panel is synchronized with the backlight. For example, to make a segment appear red, the segment is only turned ON when the backlight is red, and to make a segment appear magenta, the segment is turned ON when the backlight is blue, and it continues to be ON while the backlight becomes red, and it turns OFF when the backlight becomes green. To make a segment appear black, the segment is always turned ON. An FSC LCD divides a color image into 3 images (one Red, one Green and one Blue) and it displays them in order. Due to persistence of vision, the 3 monochromatic images appear as one color image. An FSC LCD needs an LCD panel with a refresh rate of 180 Hz, and the response time is reduced to just 5 milliseconds when compared with normal STN LCD panels which have a response time of 16 milliseconds.
Samsung introduced UFB (Ultra Fine & Bright) displays back in 2002, utilized the super-birefringent effect. It has the luminance, color gamut, and most of the contrast of a TFT-LCD, but only consumes as much power as an STN display, according to Samsung. It was being used in a variety of Samsung cellular-telephone models produced until late 2006, when Samsung stopped producing UFB displays. UFB displays were also used in certain models of LG mobile phones.
Twisted nematic displays contain liquid crystals that twist and untwist at varying degrees to allow light to pass through. When no voltage is applied to a TN liquid crystal cell, polarized light passes through the 90-degrees twisted LC layer. In proportion to the voltage applied, the liquid crystals untwist changing the polarization and blocking the light"s path. By properly adjusting the level of the voltage almost any gray level or transmission can be achieved.
In-plane switching is an LCD technology that aligns the liquid crystals in a plane parallel to the glass substrates. In this method, the electrical field is applied through opposite electrodes on the same glass substrate, so that the liquid crystals can be reoriented (switched) essentially in the same plane, although fringe fields inhibit a homogeneous reorientation. This requires two transistors for each pixel instead of the single transistor needed for a standard thin-film transistor (TFT) display. The IPS technology is used in everything from televisions, computer monitors, and even wearable devices, especially almost all LCD smartphone panels are IPS/FFS mode. IPS displays belong to the LCD panel family screen types. The other two types are VA and TN. Before LG Enhanced IPS was introduced in 2001 by Hitachi as 17" monitor in Market, the additional transistors resulted in blocking more transmission area, thus requiring a brighter backlight and consuming more power, making this type of display less desirable for notebook computers. Panasonic Himeji G8.5 was using an enhanced version of IPS, also LGD in Korea, then currently the world biggest LCD panel manufacture BOE in China is also IPS/FFS mode TV panel.
In 2015 LG Display announced the implementation of a new technology called M+ which is the addition of white subpixel along with the regular RGB dots in their IPS panel technology.
Most of the new M+ technology was employed on 4K TV sets which led to a controversy after tests showed that the addition of a white sub pixel replacing the traditional RGB structure would reduce the resolution by around 25%. This means that a 4K TV cannot display the full UHD TV standard. The media and internet users later called this "RGBW" TVs because of the white sub pixel. Although LG Display has developed this technology for use in notebook display, outdoor and smartphones, it became more popular in the TV market because the announced 4K UHD resolution but still being incapable of achieving true UHD resolution defined by the CTA as 3840x2160 active pixels with 8-bit color. This negatively impacts the rendering of text, making it a bit fuzzier, which is especially noticeable when a TV is used as a PC monitor.
In 2011, LG claimed the smartphone LG Optimus Black (IPS LCD (LCD NOVA)) has the brightness up to 700 nits, while the competitor has only IPS LCD with 518 nits and double an active-matrix OLED (AMOLED) display with 305 nits. LG also claimed the NOVA display to be 50 percent more efficient than regular LCDs and to consume only 50 percent of the power of AMOLED displays when producing white on screen.
This pixel-layout is found in S-IPS LCDs. A chevron shape is used to widen the viewing cone (range of viewing directions with good contrast and low color shift).
Vertical-alignment displays are a form of LCDs in which the liquid crystals naturally align vertically to the glass substrates. When no voltage is applied, the liquid crystals remain perpendicular to the substrate, creating a black display between crossed polarizers. When voltage is applied, the liquid crystals shift to a tilted position, allowing light to pass through and create a gray-scale display depending on the amount of tilt generated by the electric field. It has a deeper-black background, a higher contrast ratio, a wider viewing angle, and better image quality at extreme temperatures than traditional twisted-nematic displays.
Blue phase mode LCDs have been shown as engineering samples early in 2008, but they are not in mass-production. The physics of blue phase mode LCDs suggest that very short switching times (≈1 ms) can be achieved, so time sequential color control can possibly be realized and expensive color filters would be obsolete.
Some LCD panels have defective transistors, causing permanently lit or unlit pixels which are commonly referred to as stuck pixels or dead pixels respectively. Unlike integrated circuits (ICs), LCD panels with a few defective transistors are usually still usable. Manufacturers" policies for the acceptable number of defective pixels vary greatly. At one point, Samsung held a zero-tolerance policy for LCD monitors sold in Korea.ISO 13406-2 standard.
Dead pixel policies are often hotly debated between manufacturers and customers. To regulate the acceptability of defects and to protect the end user, ISO released the ISO 13406-2 standard,ISO 9241, specifically ISO-9241-302, 303, 305, 307:2008 pixel defects. However, not every LCD manufacturer conforms to the ISO standard and the ISO standard is quite often interpreted in different ways. LCD panels are more likely to have defects than most ICs due to their larger size. For example, a 300 mm SVGA LCD has 8 defects and a 150 mm wafer has only 3 defects. However, 134 of the 137 dies on the wafer will be acceptable, whereas rejection of the whole LCD panel would be a 0% yield. In recent years, quality control has been improved. An SVGA LCD panel with 4 defective pixels is usually considered defective and customers can request an exchange for a new one.
Some manufacturers, notably in South Korea where some of the largest LCD panel manufacturers, such as LG, are located, now have a zero-defective-pixel guarantee, which is an extra screening process which can then determine "A"- and "B"-grade panels.clouding (or less commonly mura), which describes the uneven patches of changes in luminance. It is most visible in dark or black areas of displayed scenes.
The zenithal bistable device (ZBD), developed by Qinetiq (formerly DERA), can retain an image without power. The crystals may exist in one of two stable orientations ("black" and "white") and power is only required to change the image. ZBD Displays is a spin-off company from QinetiQ who manufactured both grayscale and color ZBD devices. Kent Displays has also developed a "no-power" display that uses polymer stabilized cholesteric liquid crystal (ChLCD). In 2009 Kent demonstrated the use of a ChLCD to cover the entire surface of a mobile phone, allowing it to change colors, and keep that color even when power is removed.
In 2004, researchers at the University of Oxford demonstrated two new types of zero-power bistable LCDs based on Zenithal bistable techniques.e.g., BiNem technology, are based mainly on the surface properties and need specific weak anchoring materials.
Resolution The resolution of an LCD is expressed by the number of columns and rows of pixels (e.g., 1024×768). Each pixel is usually composed 3 sub-pixels, a red, a green, and a blue one. This had been one of the few features of LCD performance that remained uniform among different designs. However, there are newer designs that share sub-pixels among pixels and add Quattron which attempt to efficiently increase the perceived resolution of a display without increasing the actual resolution, to mixed results.
Spatial performance: For a computer monitor or some other display that is being viewed from a very close distance, resolution is often expressed in terms of dot pitch or pixels per inch, which is consistent with the printing industry. Display density varies per application, with televisions generally having a low density for long-distance viewing and portable devices having a high density for close-range detail. The Viewing Angle of an LCD may be important depending on the display and its usage, the limitations of certain display technologies mean the display only displays accurately at certain angles.
Temporal performance: the temporal resolution of an LCD is how well it can display changing images, or the accuracy and the number of times per second the display draws the data it is being given. LCD pixels do not flash on/off between frames, so LCD monitors exhibit no refresh-induced flicker no matter how low the refresh rate.
Color performance: There are multiple terms to describe different aspects of color performance of a display. Color gamut is the range of colors that can be displayed, and color depth, which is the fineness with which the color range is divided. Color gamut is a relatively straight forward feature, but it is rarely discussed in marketing materials except at the professional level. Having a color range that exceeds the content being shown on the screen has no benefits, so displays are only made to perform within or below the range of a certain specification.white point and gamma correction, which describe what color white is and how the other colors are displayed relative to white.
Brightness and contrast ratio: Contrast ratio is the ratio of the brightness of a full-on pixel to a full-off pixel. The LCD itself is only a light valve and does not generate light; the light comes from a backlight that is either fluorescent or a set of LEDs. Brightness is usually stated as the maximum light output of the LCD, which can vary greatly based on the transparency of the LCD and the brightness of the backlight. Brighter backlight allows stronger contrast and higher dynamic range (HDR displays are graded in peak luminance), but there is always a trade-off between brightness and power consumption.
Low power consumption. Depending on the set display brightness and content being displayed, the older CCFT backlit models typically use less than half of the power a CRT monitor of the same size viewing area would use, and the modern LED backlit models typically use 10–25% of the power a CRT monitor would use.
Usually no refresh-rate flicker, because the LCD pixels hold their state between refreshes (which are usually done at 200 Hz or faster, regardless of the input refresh rate).
No theoretical resolution limit. When multiple LCD panels are used together to create a single canvas, each additional panel increases the total resolution of the display, which is commonly called stacked resolution.
LCDs can be made transparent and flexible, but they cannot emit light without a backlight like OLED and microLED, which are other technologies that can also be made flexible and transparent.
As an inherently digital device, the LCD can natively display digital data from a DVI or HDMI connection without requiring conversion to analog. Some LCD panels have native fiber optic inputs in addition to DVI and HDMI.
Limite
Ms.Josey
Ms.Josey