led backlit lcd panel free sample

LED LCD backlights are small light strips, or light sources, contained inside a display, TV, or monitor to provide lighting for the screen. All LED TVs are LCD panels with LED backlighting. A common misconception is that LED displays are different from LCD when fundamentally they are the same. LED is better described as a sub-set of LCD devices.

LCD is an acronym for Liquid Crystal Display, which is a type of monitor or screen—and flat-panel technology—that relies on thousands or millions of pixels, arranged in a rectangular grid. When an LCD is turned on, each pixel takes on a red, green, or blue sub-pixel (RGB) that is either enabled or disabled. When the pixels are off, the individual section appears black, and when all of the sub-pixels are on, it appears white. Collectively, the arranged pixels provide the sharp image on the display by being in either an on or off configuration.

The LED backlight illuminates the pixels, from behind, making them appear richer and brighter. Not all LCDs have a backlight, and for those that do, not all of them utilize LED backlighting. Some displays also use CCFL lighting or Cold-Cathode Fluorescent Lamps. Although, it should be noted that CCFL displays are being phased out in favor of LED-backlit panels.

The liquid crystals inside an LCD panel don’t have any illumination on their own and require the light to come from a separate component, which, in this case, is provided by the LED backlighting.

Older display types, such as cathode ray tubes (CRT) produce illumination already and so they do not need an additional light source like LCD devices.

While it can be confusing at first, LED-backlit panels are different from a full LED. LED-backlit panels have LED strips lining the edges of the screen whereas full HD illuminates the entirety of the display often with higher brightness and color accuracy. Full LED panels achieve this thanks to an evenly distributed light source across the rear of the set.

This changes the picture on the display, particularly when it comes to dark scenes and true black colors. On an LED-backlit display, for example, dark scenes may appear washed out because of how the light is focused on the edges and spreads thinly into the center.

Full LEDs, on the other hand, can achieve true blacks, with even brightness levels because the light spreads across the entire panel accurately. That also means the lights in the full-LED panel can be disabled or turned off individually to create a darker image.

Because both types are fundamentally LCD panels, both LED and LED-backlit displays produce bright and vivid pictures. However, scenes may appear brighter or slightly washed out, depending on how the light source is distributed, such as from edge backlighting versus evenly distributed lighting. If you prefer a more accurate picture, full LED panels are the way to go, but they are more expensive.

Similar to TVs and other displays, an LED-backlit LCD monitor is an LCD panel with LED backlights. What often sets a monitor or computer monitor apart from standard displays is they don’t include a built-in tuner, which is needed to access cable. They often include different video or display ports, such as HDMI, DisplayPort, VGA, and so on. They"re designed to be used as a primary or secondary display for desktop computers, laptops, and beyond.

Monitors are generally full LED panels with a fully distributed light source. This allows them to provide a brighter and sharper image overall, which is ideal for computer-related activities and media.

LED-backlit TVs, monitors, and displays are used in many different places including ATMs, cash registers, digital billboards, fitness equipment like treadmills, vehicle infotainment systems, gas station pumps, Pachinko, and casino machines, mobile devices, and much more.

To clean a flat-screen TV, turn off the device and use a dry microfiber cloth to gently wipe the screen. If necessary, dampen the cloth with distilled water or an equal ratio of distilled water to white vinegar.

While all LED TVs are LCD TVs, not all LCD TVs are LED TVs. If a TV is marketed as LCD with no mention of LED, then it probably uses a different type of backlighting such as CCFL.

Toshiba Mobile Display Co., Ltd. (TMD) has announced the development of a new color active-matrix thin-film transistor (TFT) liquid crystal display (LCD) module lineup for industrial applications. The new display modules incorporate light-emitting diode (LED) backlighting systems offering an MTBF3 of 100,000 hours. The modules are designed to satisfy the requirements of a broad range of industrial applications, such as test and measurement equipment, medical equipment, mobile computing devices and more, utilizing the latest LED backlight technology. The series includes eight new LCD products, available in four screen sizes (5.7-inch, 8.4-inch, 10.4-inch, and 12.1-inch).

Compared to CCFL (cold-cathode fluorescent lamp) backlit displays, LED-backlit displays feature superior characteristics such as lower electromagnetic noise and lower power consumption, and offer a wider adjustable luminance range. The mercury-free1 LED-backlit displays also reduce environmental impact, in terms of both material content and energy consumption. Also, the new LED-backlit displays do not require the high-voltage and high-frequency circuits needed to control luminance in CCFL-backlit displays, thus enabling a higher level of flexibility in system design in terms of safety, electromagnetic interference (EMI) compensation, and system architecture.

In 2008, ahead of all other competitors, TMD started volume production of a new series of industrial TFT LCD panels that incorporated an LED backlight system with 70,000 hours MTBF3 at ordinary room temperatures (25°C). This year, in a new development, TMD has succeeded in implementing LED backlight systems with an MTBF3 of 100,000 hours at ordinary room temperatures (25°C). The innovative backlight system achieves increased longevity through design optimization for heat dissipation and luminous efficiency. TMD expects to start volume production of the new LCD display lineup in the next half.

The successful development of a backlight system with an MTBF3 of 100,000 hours (approximately 11.4 years) fulfills typical product longevity requirements for industrial applications with frequent or continuous operation, thereby making the backlighting system essentially maintenance-free. The modules have been designed with a replaceable backlight structure to accommodate product longevity requirements encountered in some harsh industrial environments. Furthermore, TMD has added LED driver circuitry into the electrical interface for the displays, to simplify design-in time and cost.

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.

To better close the local-dimming quality gap between edge-lit TVs and full-array back-lit TVs, manufacturers like Sony and Samsung developed their own advanced edge lighting forms. Sony’s technology is known as “Slim Backlight Master Drive,” while Samsung has “Infinite Array” employed in its line of QLED TVs. These keep the slim form factor achievable through edge-lit design and local dimming quality more on par with full-array backlighting.

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.

“Direct local dimming” is essentially the same thing as full-array dimming, just with fewer LEDs spread further apart in the array. However, it’s worth noting that many manufacturers do not differentiate “direct local dimming” from full-array dimming as two separate forms of local dimming. We still feel it’s important to note the difference, as fewer, further-spaced LEDs will not have the same accuracy and consistency as full-array displays.

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.

As if it wasn’t already confusing enough, once you begin exploring the world of modern display technology, new acronyms crop up. The two you’ll most commonly find are OLED and QLED.

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.

For a further description of QLED and its features, read our list of the best TVs you can buy. The article further compares the qualities of both QLED and OLED TV; however, we also recommend checking outfor a side-by-side look at these two top-notch technologies.

There are more even displays to become familiar with, too, including microLED and Mini-LED, which are lining up to be the latest head-to-head TV technologies. Consider checking out how the two features compare to current tech leaders in

In the world of TV technology, there’s never a dull moment. However, with this detailed research, we hope you feel empowered to make an informed shopping decision and keep your Best Buy salesperson on his or her toes.

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