Flat-panel displays are thin panels of glass or plastic used for electronically displaying text, images, or video. Liquid crystal displays (LCD), OLED (organic light emitting diode) and microLED displays are not quite the same; since LCD uses a liquid crystal that reacts to an electric current blocking light or allowing it to pass through the panel, whereas OLED/microLED displays consist of electroluminescent organic/inorganic materials that generate light when a current is passed through the material. LCD, OLED and microLED displays are driven using LTPS, IGZO, LTPO, and A-Si TFT transistor technologies as their backplane using ITO to supply current to the transistors and in turn to the liquid crystal or electroluminescent material. Segment and passive OLED and LCD displays do not use a backplane but use indium tin oxide (ITO), a transparent conductive material, to pass current to the electroluminescent material or liquid crystal. In LCDs, there is an even layer of liquid crystal throughout the panel whereas an OLED display has the electroluminescent material only where it is meant to light up. OLEDs, LCDs and microLEDs can be made flexible and transparent, but LCDs require a backlight because they cannot emit light on their own like OLEDs and microLEDs.

Liquid-crystal display (or LCD) is a thin, flat panel used for electronically displaying information such as text, images, and moving pictures. They are usually made of glass but they can also be made out of plastic. Some manufacturers make transparent LCD panels and special sequential color segment LCDs that have higher than usual refresh rates and an RGB backlight. The backlight is synchronized with the display so that the colors will show up as needed. The list of LCD manufacturers:

Organic light emitting diode (or OLED displays) is a thin, flat panel made of glass or plastic used for electronically displaying information such as text, images, and moving pictures. OLED panels can also take the shape of a light panel, where red, green and blue light emitting materials are stacked to create a white light panel. OLED displays can also be made transparent and/or flexible and these transparent panels are available on the market and are widely used in smartphones with under-display optical fingerprint sensors. LCD and OLED displays are available in different shapes, the most prominent of which is a circular display, which is used in smartwatches. The list of OLED display manufacturers:

MicroLED displays is an emerging flat-panel display technology consisting of arrays of microscopic LEDs forming the individual pixel elements. Like OLED, microLED offers infinite contrast ratio, but unlike OLED, microLED is immune to screen burn-in, and consumes less power while having higher light output, as it uses LEDs instead of organic electroluminescent materials, The list of MicroLED display manufacturers:

LCDs are made in a glass substrate. For OLED, the substrate can also be plastic. The size of the substrates are specified in generations, with each generation using a larger substrate. For example, a 4th generation substrate is larger in size than a 3rd generation substrate. A larger substrate allows for more panels to be cut from a single substrate, or for larger panels to be made, akin to increasing wafer sizes in the semiconductor industry.

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There’s a variety of display panel out there and even more on the way. But looking at all the different types of panels can be baffling. They come in various acronyms, and many of those acronyms are confusingly similar. How do LCD, LED and OLED compare? What about the different types of LCD panels? And how do these different technologies impact your viewing experience for things like gaming? To help, we’ve created this guide so you can gain a firm understanding of today’s display panel technology and which features really matter.

The first type of panels we’ll cover are LCD (liquid crystal display) panels. The main thing to understand about LCD panels is that they all use a white backlight (or sidelight, etc.). They work by shining a bright white light into your eyes, while the rest of the panel is for changing this backlight into individual pixels.

LED stands for light-emitting diode. You’ll often see LCD panels that are LED, but that doesn’t necessarily mean much when choosing an LCD. LED is just a different type of backlight compared to the old cold cathode backlights. While you could congratulate yourself on not using mercury, which is found in cathodes, at this point all LCDs use LED backlights anyway.

The second thing to understand is that LCDs take advantage of a phenomena known as polarization. Polarization is the direction in which the light wave is oscillating, or swinging back and forth at the same speed. Light comes out of the backlight unpolarized. It then passes through one polarizer, which makes all the light oscillate the same way.

Then there’s the “liquid crystal” part. A liquid crystal in this case is a crystal structure that can change the polarization of light passing through it. A liquid crystal in the rest, or off, state is arranged to not change the polarization of the light. This means that when the light reaches a second polarizer, oriented oppositely from the first polarizer, all the light is blocked. But when you apply a voltage, you turn the liquid crystal into some percentage of an “on” state. This then changes a percentage of the polarization of the light passing through to meet the orientation of the second polarizer, allowing it to pass through and become visible to your eye.

Now you have an on and off (and between) switch for light. To produce color all that’s needed is three color filters, red, green and blue, that block all light other than that color from coming through. The difference between different types of LCD panels is mostly in how this in-between liquid crystal part works.

This design allows for fast response times (the time between the panel getting the frame it’s supposed to display and actually displaying it). It also allows for fast refresh rates. Consequently, TN panels are the only 240 hertz (Hz) gaming monitors available right now.

TN panels are cheap but suffer from poor viewing angles due to the “twist” only being aligned in one direction for viewing the panel straight on. They can also have poor color and contrast due to this twist mechanism not being the most precise or accurate.

VA stands for vertical alignment, again referring to the crystal alignment. These came about in the 1990s. Instead of using liquid crystals to twist a light’s polarization, a VA panel’s liquid crystals are aligned either perpendicular (vertical to) or parallel (horizontal to) the two polarizers. In the off state, the crystals are perpendicular to the two opposing polarizers. In the on state, the crystals begin to align horizontally, changing the polarization to match the second polarizer and allowing the light to go through the crystals.

This structure produces deeper blacks and better colors than TN panels. And multiple crystal alignments (shifted a bit off axis from each other) can allow for better viewing angles compared to TN panels.

However, VA panels come with a tradeoff, as they are often more expensive than TN panels and tend to have lower refresh rates and slower response times than TN panels. Consequently, you won’t see quite as many VA panel gaming monitors.

IPS stands for in-plane switching. These panels debuted after TN panels in the mid-1990s. The crystals are always horizontal to the two polarizers and twist 90° horizontally to go from off to on. Part of this design requires the two electrodes (which apply current to the liquid crystal to change its state) to be on the same glass substrate, instead of aligned with each other on the sandwiching glass substrates above and below the crystal (as in other types of LCDs). This, in turn, blocks a bit more light than both TN and VA panels.

IPS panels have the best viewing angles and colors of any LCD monitor type, thanks to its crystal alignment always lining up with the viewer. And while they don’t offer as fast a response time or refresh rate as TN panels, clever engineering has still gotten them to 144hz, and with nice viewing angles you’re not necessarily going wrong with an IPS gaming panel.

How do LCD panels go about reaching HDR brightness when incorrect polarization and color filters block so much light?The answer is quantum dots. These clever little things are molecules that absorb light and then re-emit that light in the color you engineered them to.

Today’s quantum dot layers usually go between a blue backlight and the polarization step, and are often used to produce red and green that more closely matches the color filters, so more light passes through them. This allows more of the backlight to come through instead of being blocked by the color filters, it can also reduce crosstalk, or colors slipping through the wrong subpixel, ensuring better colors of LCDs.

Other uses of quantum dots are being tried, however. One promising one is using QD molecules to replace the color filters entirely, allowing even more light through. Because LCD backlights produce more light than OLED panels (more on those below), this would allow LCDs to become the brightest displays around.

Motion blur/ghosting can be a result of how long an image takes to switch from one to another and how long an image is displayed on screen (persistence). But both of these phenomena differ greatly between individual LCD panels regardless of underlying LCD tech. And both are often better controlled by higher refresh rates, rather than clever panel engineering, at least for LCD displays.

Choosing an LCD panel based on underlying LCD tech should be more about cost vs desired contrast, viewing angles and color reproduction than expected blur, or other gaming attributes. Maximum refresh rate and response time should be listed in any respectable panel’s specs. Other gaming tech, such as strobe, which flashes the backlight on and off quickly to reduce persistence, may not be listed at all and is not part of the underlying type of LCD used. For that kind of info you’ll have to check the detailed reviews here on our site.

OLED, or organic light emitting diode, panels, are different from LCDs. There are no polarization tricks here. Instead, each pixel (or subpixel of red, green, or blue) lights itself up as a voltage is applied to a giant complex molecule called, yep, an organic light emitting diode. The color emitted is dependent on the molecule in question, and brightness is dependent on the voltage applied. OLEDs can reach HDR brightness because their molecules put out the right colors to begin with without being blocked.

Due to its approach to color and brightness, OLEDs have great contrast ratios. There’s no need to block a backlight, so there’s no worries about light bleeding through. Blacks are very black, and colors look great. OLEDs can also strobe, or flash off and on quickly to lower persistence. They can also use a trick called rolling scan.This turns blocks of the screen on and off one at a time, from top to bottom in a roll. This is all done as the image is sent to the screen, which cuts down on persistence blur a lot. This is why every major VR headset that can afford it uses OLED panels today.

Unfortunately, that’s where the advantages of OLED end. Refresh rates of OLED panels have never surpassed about 90Hz. And they’re quite expensive. A large part of that $1,000 iPhone X price is due to its OLED display. The current molecules used in OLEDs also degrade relatively quickly over time, especially those used for the color blue(opens in new tab), making the screen less and less bright.

OLEDs were also supposed to use less power than LCDs, but newer, giant OLED molecules that take less voltage to turn on have yet to appear. And while molecules covering the colors of the P3 HDR gamut are out today, those covering the larger BT.2020 gamut have yet to be found commercially. So OLEDs, while once promising and seemingly the future, have yet to live up to that promise.

A relevant question: If our fastest gaming displays are 240Hz TN panels now, just how fast do we need to go anyway? Well, a 2015 study places maximum human perception at 500Hz. So from that perspective, we’re halfway there. But that’s halfway there with today’s HDR, and not in lightfield 3D, or other possible advancements. And mobile devices could always use displays that take up less power.

In other words, in order to get fancy 3D effects, or much higher brightness, or any other desirable features, a different, new type of panel may be required. MicroLED tech is one such technology; think of it as OLED without the organic part and with the potential to improve contrast, response times and energy usage over standard LED panels. If you want to know more you can go here, but the real takeaway is that MicroLEDs work almost exactly like OLEDs.

Principal Display Panel or Panels means that part, or those parts of a label that are so designed as to most likely be displayed, presented, shown or examined under normal and customary conditions of display or purchase. Whenever a principal display panel appears more than once, all requirements pertaining to the “principal display panel” shall pertain to all such “principal display panels.”

Review Panel means a panel responsible for determining whether a reasonable basis exists for finding a violation of BSEF Rules, and for authorizing the issuance of notices of chargers against Persons alleged to have committed violations if the Review Panel believes that the matter should be adjudicated.

District Evaluation Advisory Committee means a group created to oversee and guide the planning and implementation of the Board of Education"s evaluation policies and procedures as set forth in N.J.A.C. 6A:10-2.3.

Principal display panel means that part of a label that is most likely to be displayed, presented, shown, or examined under normal and customary conditions of display for retail sale.

Urban Coordinating Council Empowerment Neighborhood means a neighborhood given priority access to State resources through the New Jersey Redevelopment Authority.

Licensed mental health professional or "LMHP" means a physician, licensed clinical psychologist, licensed professional counselor, licensed clinical social worker, licensed substance abuse treatment practitioner, licensed marriage and family therapist, certified psychiatric clinical nurse specialist, licensed behavior analyst, or licensed psychiatric/mental health nurse practitioner.

Design Criteria Professional means a firm who holds a current certificate of registration under Chapter 481 of the Florida Statutes, to practice architecture or landscape architecture, or a firm who holds a current certificate as a registered engineer under Chapter 471 of the Florida Statutes, to practice engineering, and who is employed by or under contract to the District to provide professional architect services, landscape architect services, or engineering services in connection with the preparation of the Design Criteria Package.

Clinical nurse specialist means a registered nurse with relevant post-basic qualifications and 12 months’ experience working in the clinical area of his/her specified post-basic qualification, or a minimum of four years’ post-basic registration experience, including three years’ experience in the relevant specialist field and who satisfies the local criteria.

Selection Committee means a committee of individual(s) who evaluate and rank proposals; conduct negotiations; and makes a contract award recommendation to the District and its respective Committees.

Drug paraphernalia means all equipment, products, and materials of any kind which are used, intended for use, or designed for use in planting, propagating, cultivating, growing, harvesting, manufacturing, compounding, converting, producing, processing, preparing, testing, analyzing, packaging, repackaging, storing, containing, concealing, transporting, injecting, ingesting, inhaling, or otherwise introducing into the human body a controlled substance in violation of s. 877.111, Florida Statutes. Drug paraphernalia is deemed to be contraband.

traditional leader means the leader of a traditional authority that had been identified by the MEC in terms of section 81(2) of the Structures Act to participate in the proceedings of a council.

Licensed Professional Engineer means a person acceptable to Buyer in its reasonable judgment who (a) is licensed to practice engineering in California, (b) has training and experience in the power industry specific to the technology of the Project, (c) has no economic relationship, association, or nexus with Seller or Buyer, other than to meet the obligations of Seller pursuant to this Agreement, (d) is not a representative of a consultant, engineer, contractor, designer or other individual involved in the development of the Project or of a manufacturer or supplier of any equipment installed at the Project, and (e) is licensed in an appropriate engineering discipline for the required certification being made.

Back in 2016, to determine if the TV panel lottery makes a significant difference, we bought three different sizes of the Samsung J6300 with panels from different manufacturers: a 50" (version DH02), a 55" (version TH01), and a 60" (version MS01). We then tested them with the same series of tests we use in all of our reviews to see if the differences were notable.

Our Samsung 50" J6300 is a DH02 version, which means the panel is made by AU Optronics. Our 55" has an original TH01 Samsung panel. The panel in our 60" was made by Sharp, and its version is MS01.

Upon testing, we found that each panel has a different contrast ratio. The 50" AUO (DH02) has the best contrast, at 4452:1, followed by the 60" Sharp (MS01) at 4015:1. The Samsung 55" panel had the lowest contrast of the three: 3707:1.

These results aren"t really surprising. All these LCD panels are VA panels, which usually means a contrast between 3000:1 and 5000:1. The Samsung panel was quite low in that range, leaving room for other panels to beat it.

For contrast ratio, we consider a difference of about 500:1 to be noticeable. This means that if you put the 50" and the 55" next to each other in a dark room, you"ll see a difference in terms of the blacks, but it won"t be huge. While we expect contrast to vary between units, a difference like this is likely an exception.

The motion blur results are really interesting. The response time of the 55" TH01 Samsung panel is around double that of the Sharp and AUO panels. This is even consistent across all 12 transitions that we measured.

For our measurements, a difference in response time of 10 ms starts to be noticeable. All three are within this range, so the difference isn"t very noticeable to the naked eye, and the Samsung panel still performs better than most other TVs released around the same time.

We also got different input lag measurements on each panel. This has less to do with software, which is the same across each panel, and more to do with the different response times of the panels (as illustrated in the motion blur section). To measure input lag, we use the Leo Bodnar tool, which flashes a white square on the screen and measures the delay between the signal sent and the light sensor detecting white. Therefore, the tool"s input lag measurement includes the 0% to 100% response time of the pixel transition. If you look at the 0% to 100% transitions that we measured, you will see that the 55" takes about 10 ms longer to transition from black to white.

All three have bad viewing angles, as expected for VA panels. If you watch TV at an angle, most likely none of these TVs will satisfy you. The picture quality degrades at about 20 degrees from the side. The 60" Sharp panel is worse than the other ones though. In the video, you can see the right side degrading sooner than the other panels.

It"s unfortunate that manufacturers sometimes vary the source of their panels and that consumers don"t have a way of knowing which one they"re buying. Overall though, at least in the units we tested, the panel lottery isn"t something to worry about. While there are differences, the differences aren"t big and an original Samsung panel isn"t necessarily better than an outsourced one. It"s also fairly safe to say that the same can be said of other brands. All panels have minute variations, but most should perform within the margin of error for each model.

Many TVs use LCD (Liquid Crystal Display) panels that are lit by LED backlights. There are two popular types of LCD panels: In-Plane Switching (IPS) and Vertical Alignment (VA), and there are two main differences between each type. A VA panel usually has a high contrast ratio and narrow viewing angles. However, an IPS panel has low contrast and wide viewing angles. These are the main differences between each, and for the most part, panel type doesn"t affect other aspects of picture quality, like peak brightness, color gamut, or color accuracy.

For the purposes of this article, we"re going to compare two LED-backlit LCD TVs: the Sony X800H, which has an IPS panel, and the Hisense H9G, which has a VA panel. Due to their different panel types, there are three noticeable differences in picture quality: viewing angles, contrast, and black uniformity, so we"re going to look at each one.

Viewing angle refers to the angle at which you can watch the TV without seeing a noticeable drop in picture quality. IPS TVs are the clear winner here, as the image remains accurate when viewing from the side - you can see the differences in the videos above. This is their main advantage over VA panels. Most VA panel TVs have a noticeable loss in image accuracy when viewing from the side. The narrow viewing angle of VA-type TVs is also problematic when the TV is used as a PC monitor from up close since the edges of the display look washed out.

VA panels are far superior to IPS panels when it comes to this, so if you tend to watch movies in the dark, you likely want to get a TV with a VA panel. Most TVs use VA panels due to this main advantage, and high-end models may have a local dimming feature that further enhances black levels. On the other hand, IPS panels normally have low contrast, so blacks look closer to gray, but you may not notice the difference in contrast in bright environments.

Our black uniformity tests determine how well a TV displays a dark scene with a bright image in the center. Ideally, you want to see a completely black screen with the center cross being the only part that"s lit up, and this is important for people watching movies. No LED TV has perfect uniformity, and unlike viewing angles and contrast, the panel type doesn"t completely determine its black uniformity. However, most VA panels that we"ve tested have good black uniformity, while most IPS panels have sub-par black uniformity. This doesn"t mean that every VA panel TV has good uniformity, as this can change between units, and you can also improve uniformity using the local dimming feature.

LCDs function by having liquid crystals in little groups to form the pixels. These crystals react and change position when charged with electricity and, depending on their position, they allow a certain color of light to pass through.

There"s also another type of IPS panel, called Plane-to-Line Switching (PLS), which can be seen with the Sony X800H. This panel type was designed by Samsung and technically performs the same as an IPS panel. When you compare the pixels visually, IPS panels look like chevrons, VA looks like very straight rectangles, and PLS looks like round-edged capsules. You can learn more about pixels here.

The way the pixels are laid out can also affect text clarity. Many IPS panels, like the ones on the Sony X800H or the LG SK9000, use RGB sub-pixel layouts, while many VA panels have a BGR layout, like on the Hisense H9G. The sub-pixel layout doesn"t directly affect picture quality unless you"re using it as a PC monitor. Some applications may expect an RGB layout, so if you have a BGR sub-pixel layout, text may not look clear. You may need to increase the text scaling to read it properly, but this issue isn"t common with an RGB layout. You can learn more about it here.

Unlike LED TVs, OLEDs don"t use a backlight and instead have self-emitting pixels. This allows the pixels to individually turn on and off, resulting in perfect blacks. This means that they also have perfect black uniformity as there"s no blooming around bright objects like on some LED TVs. They also have wide viewing angles, sometimes even wider than some IPS panels, so OLEDs are a good choice for wide seating arrangements.

Samsung released quantum dot TVs in 2015, which they later labeled as QLED in 2017. These TVs include a quantum dot layer between the LED backlights and the LCD panel to achieve a wider color gamut. Other companies like Vizio and TCL also use this quantum dot technology on their TVs. Adding this extra quantum dot layer doesn"t change the characteristics of the panel type; the VA panel on the TCL 6 Series/S635 2020 QLED still has a high contrast ratio and narrow viewing angles. Although most QLED TVs use VA panels, you can easily use an IPS panel as well.

Manufacturers have tried different techniques to improve the viewing angles on VA panels over the years, aiming to produce a perfect LCD panel with both wide viewing angles and high contrast. While they have yet to achieve that goal, a few TVs have hit the market that try to combine the best of both panel types. The first TVs with this viewing angle technology came out in 2018, and only a few high-end models like the Samsung Q90/Q90T QLED and the Sony X950H had this technology in 2020. These TVs are a bit unique, delivering noticeably better viewing angles than their pure VA counterparts, but still worse than true IPS panels. This comes at the expense of a lower contrast ratio, as these TVs have worse native contrast than most VA panels, but they"re still better than IPS panels. Combined with their local dimming features, they still produce deep blacks.

Between IPS and VA panels, neither technology is inherently superior to the other as they both serve different purposes. In general, IPS TVs have wide viewing angles suitable for when you want to watch the big game or your favorite show in a large seating arrangement. They"re also beneficial for use as a PC monitor since the edges remain accurate if you sit up close. However, VA panels are a better choice for watching content in dark rooms, as their improved contrast allows them to display deep blacks. Choosing between the two is a series of trade-offs and qualities, so choosing the best TV for your needs depends on your usage.

NDSsi uses only “Grade A” LCD panels in all of its products, while many competitors use “Grade B” panels in order to save cost, and as a result compromise quality. In medical applications, it is important not to compromise the quality of the displayed image since it is often the basis for making clinical decisions. The following tables and images show the differences between “Grade A” and “Grade B” LCD panels in terms of different types of allowable defects.

There are essentially two different types of pixel defects, bright (stuck pixels) and dark (dead pixels).The table and images below show the differences between Grade A and Grade B LCD panels in terms of allowable pixel defects.

Shopping for a new TV is like wading through a never-ending pool of tech jargon, display terminology, and head-spinning acronyms. It was one thing when 4K resolution landed in the homes of consumers, with TV brands touting the new UHD viewing spec as a major marketing grab. But over the last several years, the plot has only continued to thicken when it comes to three- and four-letter acronyms with the introduction of state-of-the-art lighting and screen technology. But between OLEDs, QLEDs, mini-LEDs, and now QD-OLEDs, there’s one battle of words that rests at the core of TV vocabulary: LED versus LCD.

Despite having a different acronym, LED TV is just a specific type of LCD TV, which uses a liquid crystal display (LCD) panel to control where light is displayed on your screen. These panels are typically composed of two sheets of polarizing material with a liquid crystal solution between them. When an electric current passes through the liquid, it causes the crystals to align, so that light can (or can’t) pass through. Think of it as a shutter, either allowing light to pass through or blocking it out.

Since both LED and LCD TVs are based around LCD technology, the question remains: what is the difference? Actually, it’s about what the difference was. Older LCD TVs used cold cathode fluorescent lamps (CCFLs) to provide lighting, whereas LED LCD TVs used an array of smaller, more efficient light-emitting diodes (LEDs) to illuminate the screen.

Since the technology is better, all LCD TVs now use LED lights and are colloquially considered LED TVs. For those interested, we’ll go deeper into backlighting below, or you can move onto the Local Dimming section.

Three basic illumination forms have been used in LCD TVs: CCFL backlighting, full-array LED backlighting, and LED edge lighting. Each of these illumination technologies is different from one another in important ways. Let’s dig into each.

CCFL backlighting is an older, now-abandoned form of display technology in which a series of cold cathode lamps sit across the inside of the TV behind the LCD. The lights illuminate the crystals fairly evenly, which means all regions of the picture will have similar brightness levels. This affects some aspects of picture quality, which we discuss in more detail below. Since CCFLs are larger than LED arrays, CCFL-based LCD TVs are thicker than LED-backlit LCD TVs.

Full-array backlighting swaps the outdated CCFLs for an array of LEDs spanning the back of the screen, comprising zones of LEDs that can be lit or dimmed in a process called local dimming. TVs using full-array LED backlighting to make up a healthy chunk of the high-end LED TV market, and with good reason — with more precise and even illumination, they can create better picture quality than CCFL LCD TVs were ever able to achieve, with better energy efficiency to boot.

Another form of LCD screen illumination is LED edge lighting. As the name implies, edge-lit TVs have LEDs along the edges of a screen. There are a few different configurations, including LEDs along just the bottom, LEDs on the top and bottom, LEDs left and right, and LEDs along all four edges. These different configurations result in picture quality differences, but the overall brightness capabilities still exceed what CCFL LCD TVs could achieve. While there are some drawbacks to edge lighting compared to full-array or direct backlight displays, the upshot is edge lighting that allows manufacturers to make thinner TVs that cost less to manufacture.

Local dimming is a feature of LED LCD TVs wherein the LED light source behind the LCD is dimmed and illuminated to match what the picture demands. LCDs can’t completely prevent light from passing through, even during dark scenes, so dimming the light source itself aids in creating deeper blacks and more impressive contrast in the picture. This is accomplished by selectively dimming the LEDs when that particular part of the picture — or region — is intended to be dark.

Local dimming helps LED/LCD TVs more closely match the quality of modern OLED displays, which feature better contrast levels by their nature — something CCFL LCD TVs couldn’t do. The quality of local dimming varies depending on which type of backlighting your LCD uses, how many individual zones of backlighting are employed, and the quality of the processing. Here’s an overview of how effective local dimming is on each type of LCD TV.

TVs with full-array backlighting have the most accurate local dimming and therefore tend to offer the best contrast. Since an array of LEDs spans the entire back of the LCD screen, regions can generally be dimmed with more finesse than on edge-lit TVs, and brightness tends to be uniform across the entire screen. Hisense’s impressive U7G TVs are great examples of relatively affordable models that use multiple-zone, full-array backlighting with local dimming.

Because edge lighting employs LEDs positioned on the edge or edges of the screen to project light across the back of the LCD screen, as opposed to coming from directly behind it, it can result in very subtle blocks or bands of lighter pixels within or around areas that should be dark. The local dimming of edge-lit TVs can sometimes result in some murkiness in dark areas compared with full-array LED TVs. It should also be noted that not all LED edge-lit TVs offer local dimming, which is why it is not uncommon to see glowing strips of light at the edges of a TV and less brightness toward the center of the screen.

Since CCFL backlit TVs do not use LEDs, models with this lighting style do not have dimming abilities. Instead, the LCD panel of CCFL LCDs is constantly and evenly illuminated, making a noticeable difference in picture quality compared to LED LCDs. This is especially noticeable in scenes with high contrast, as the dark portions of the picture may appear too bright or washed out. When watching in a well-lit room, it’s easier to ignore or miss the difference, but in a dark room, it will be, well, glaring.

An OLED display uses a panel of pixel-sized organic compounds that respond to electricity. Since each tiny pixel (millions of which are present in modern displays) can be turned on or off individually, OLED displays are called “emissive” displays (meaning they require no backlight). They offer incredibly deep contrast ratios and better per-pixel accuracy than any other display type on the market.

Because they don’t require a separate light source, OLED displays are also amazingly thin — often just a few millimeters. OLED panels are often found on high-end TVs in place of LED/LCD technology, but that doesn’t mean that LED/LCDs aren’t without their own premium technology.

QLED is a premium tier of LED/LCD TVs from Samsung. Unlike OLED displays, QLED is not a so-called emissive display technology (lights still illuminate QLED pixels from behind). However, QLED TVs feature an updated illumination technology over regular LED LCDs in the form of Quantum Dot material (hence the “Q” in QLED), which raises overall efficiency and brightness. This translates to better, brighter grayscale and color and enhances HDR (High Dynamic Range) abilities.

And now to make things extra confusing, part of Samsung’s 2022 TV lineup is being billed as traditional OLEDs, although a deeper dive will reveal this is actually the company’s first foray into a new panel technology altogether called QD-OLED.

Backlit LCDs provide excellent visibility indoors, but require high-brightness backlights to produce enough brightness for for direct sunlight readability - 1000 nits or more, to be exact. All that brightness requires a lot of power to operate, making traditional high-brightness LCD signage costly in multiple ways.

Sun Vision Display panels actually turn sunlight into an asset through their reflective LCD technology.The brighter the sun shines on the display, the brighter the Sun Vision Display panel"s image becomes. All while consuming almost no power (less than 5 watts). Sun Vision Display panels are an excellent solution for sunny locations!

To create an LCD, you take two pieces ofpolarized glass. A special polymer that creates microscopic grooves in the surface is rubbed on the side of the glass that does not have the polarizing film on it. The grooves must be in the same direction as the polarizing film. You then add a coating of nematic liquid crystals to one of the filters. The grooves will cause the first layer of molecules to align with the filter"s orientation. Then add the second piece of glass with the polarizing film at a right angle to the first piece. Each successive layer of TN molecules will gradually twist until the uppermost layer is at a 90-degree angle to the bottom, matching the polarized glass filters.

If we apply an electric charge to liquid crystal molecules, they untwist. When they straighten out, they change the angle of the light passing through them so that it no longer matches the angle of the top polarizing filter. Consequently, no light can pass through that area of the LCD, which makes that area darker than the surrounding areas.

Building a simple LCD is easier than you think. Your start with the sandwich of glass and liquid crystals described above and add two transparent electrodes to it. For example, imagine that you want to create the simplest possible LCD with just a single rectangular electrode on it. The layers would look like this:

The LCD needed to do this job is very basic. It has a mirror (A) in back, which makes it reflective. Then, we add a piece of glass (B) with a polarizing film on the bottom side, and a common electrode plane (C) made of indium-tin oxide on top. A common electrode plane covers the entire area of the LCD. Above that is the layer of liquid crystal substance (D). Next comes another piece of glass (E) with an electrode in the shape of the rectangle on the bottom and, on top, another polarizing film (F), at a right angle to the first one.

The electrode is hooked up to a power source like a battery. When there is no current, light entering through the front of the LCD will simply hit the mirror and bounce right back out. But when the battery supplies current to the electrodes, the liquid crystals between the common-plane electrode and the electrode shaped like a rectangle untwist and block the light in that region from passing through. That makes the LCD show the rectangle as a black area.

There are plenty of new and confusing terms facing TV shoppers today, but when it comes down to the screen technology itself, there are only two: Nearly every TV sold today is either LCD or OLED.

The biggest between the two is in how they work. With OLED, each pixel provides its own illumination so there"s no separate backlight. With an LCD TV, all of the pixels are illuminated by an LED backlight. That difference leads to all kinds of picture quality effects, some of which favor LCD, but most of which benefit OLED.

LCDs are made by a number of companies across Asia. All current OLED TVs are built by LG Display, though companies like Sony and Vizio buy OLED panels from LG and then use their own electronics and aesthetic design.

So which one is better? Read on for their strengths and weaknesses. In general we"ll be comparing OLED to the best (read: most expensive) LCD has to offer, mainly because there"s no such thing as a cheap OLED TV (yet).

The better LCDs have local dimming, where parts of the screen can dim independently of others. This isn"t quite as good as per-pixel control because the black areas still aren"t absolutely black, but it"s better than nothing. The best LCDs have full-array local dimming, which provides even finer control over the contrast of what"s onscreen -- but even they can suffer from "blooming," where a bright area spoils the black of an adjacent dark area.

One of the main downsides of LCD TVs is a change in picture quality if you sit away from dead center (as in, off to the sides). How much this matters to you certainly depends on your seating arrangement, but also on how much you love your loved ones.

A few LCDs use in-plane switching (IPS) panels, which have better off-axis picture quality than other kinds of LCDs, but don"t look as good as other LCDs straight on (primarily due to a lower contrast ratio).

OLED doesn"t have the off-axis issue LCDs have; its image looks basically the same, even from extreme angles. So if you have a wide seating area, OLED is the better option.

Nearly all current TVs are HDR compatible, but that"s not the entire story. Just because a TV claims HDR compatibility doesn"t mean it can accurately display HDR content. All OLED TVs have the dynamic range to take advantage of HDR, but lower-priced LCDs, especially those without local-dimming backlights, do not. So if you want to see HDR content it all its dynamic, vibrant beauty, go for OLED or an LCD with local dimming.

In our tests comparing the best new OLED and LCD TVs with HDR games and movies, OLED usually looks better. Its superior contrast and lack of blooming win the day despite LCD"s brightness advantage. In other words LCD TVs can get brighter, especially in full-screen bright scenes and HDR highlights, but none of them can control that illumination as precisely as an OLED TV.

The energy consumption of LCD varies depending on the backlight setting. The lower the backlight, the lower the power consumption. A basic LED LCD with its backlight set low will draw less power than OLED.

LG has said their OLED TVs have a lifespan of 100,000 hours to half brightness, a figure that"s similar to LED LCDs. Generally speaking, all modern TVs are quite reliable.

Does that mean your new LCD or OLED will last for several decades like your parent"s last CRT (like the one pictured). Probably not, but then, why would you want it to? A 42-inch flat panel cost $14,000 in the late 90"s, and now a 65-inch TV with more than 16x the resolution and a million times better contrast ratio costs $1,400. Which is to say, by the time you"ll want/need to replace it, there will be something even better than what"s available now, for less money.

OLED TVs are available in sizes from 48 to 88 inches, but LCD TVs come in smaller and larger sizes than that -- with many more choices in between -- so LCD wins. At the high end of the size scale, however, the biggest "TVs" don"t use either technology.

You can get 4K resolution, 50-inch LCDs for around $400 -- or half that on sale. It"s going to be a long time before OLEDs are that price, but they have come down considerably.

LCD dominates the market because it"s cheap to manufacture and delivers good enough picture quality for just about everybody. But according to reviews at CNET and elsewhere, OLED wins for overall picture quality, largely due to the incredible contrast ratio. The price difference isn"t as severe as it used to be, and in the mid- to high-end of the market, there are lots of options.