This article is about light-emitting diode (LED) based displays. For LED-backlit displays, see LED-backlit LCD . For matrixed text displays, see Dot-matrix display
Not to be confused with Vacuum fluorescent display
Detail view of an LED display with a matrix of red, green and blue diodesA LED display is a flat panel display that uses an array of light-emitting diodes (LEDs) as pixels for a video display. Their brightness allows them to be used outdoors where they are visible in the sun for store signs and billboards. In recent years, they have also become commonly used in destination signs on public transport vehicles, as well as variable-message signs on highways. LED displays are capable of providing general illumination in addition to visual display, as when used for stage lighting or other decorative (as opposed to informational) purposes. LED displays can offer higher contrast ratios than a projector and are thus an alternative to traditional projection screens, and they can be used for large, uninterrupted (without a visible grid arising from the bezels of individual displays) video walls. microLED displays are LED displays with smaller LEDs, which poses significant development challenges.[1]
A LED video cube above the ice rink at Nokia Arena in Tampere, Finland.History
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Light-emitting diodes (LEDs) came into existence in 1962 and were primarily red in color for the first decade. The first practical LED was invented by Nick Holonyak in 1962 while he was at General Electric.[2]
The first practical LED display was developed at Hewlett-Packard (HP) and introduced in 1968.[3] Its development was led by Howard C. Borden and Gerald P. Pighini at HP Associates and HP Labs, who had engaged in research and development (R&D) on practical LEDs between 1962 and 1968. In February 1969, they introduced the HP Model 5082-7000 Numeric Indicator.[4] It was the first LED device to use integrated circuit (integrated LED circuit) technology,[4] and the first intelligent LED display, making it a revolution in digital display technology, replacing the Nixie tube and becoming the basis for later LED displays.[5]
Early models were monochromatic by design. The efficient Blue LED completing the color triad did not commercially arrive until the late 1980s.[1]
In the late 1980s, Aluminium Indium Gallium Phosphide LEDs arrived. They provided an efficient source of red and amber and were used in information displays. However, it was still impossible to achieve full colour. The available "green" was hardly green at all – mostly yellow, and an early blue had excessively high power consumption. It was only when Shuji Nakamura, then at Nichia Chemical, announced the development of the blue (and later green) LED based on Indium Gallium Nitride, that possibilities opened for big LED video displays.
The entire idea of what could be done with LED was given an early shake up by Mark Fisher's design for U2's PopMart Tour of 1997. He realized that with long viewing distances, wide pixel spacing could be used to achieve very large images, especially if viewed at night. The system had to be suitable for touring so an open mesh arrangement that could be rolled up for transport was used. The whole display was 52m (170ft) wide and 17m (56ft) high. It had a total of 150,000 pixels. The company that supplied the LED pixels and their driving system, SACO Technologies of Montreal, had never engineered a video system before, previously building mimic panels for power station control rooms.
Today, large displays use high-brightness diodes to generate a wide spectrum of colors. It took three decades and organic light-emitting diodes for Sony to introduce an OLED TV, the Sony XEL-1 OLED screen which was marketed in 2009. Later, at CES 2012, Sony presented Crystal LED, a TV with a true LED-display, in which LEDs are used to produce actual images rather than acting as backlighting for other types of display, as in LED-backlit LCDs which are commonly marketed as LED TVs.
Large video-capable screens
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The 2011 UEFA Champions League Final match between Manchester United and Barcelona was broadcast live in 3D format in Gothenburg (Sweden), on an EKTA screen. It had a refresh rate of 100 Hz, a diagonal of 7.11 m (23 ft 3.92 in) and a display area of 6.192×3.483 m, and was listed in the Guinness Book of Records as the largest LED 3D TV.[6][7]
Development
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Early prototypes
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A claim for the 'first all-LED flat panel television screen' is presented in this section. It was possibly developed, demonstrated and documented by James P. Mitchell in 1977. Initial public recognition came from the Westinghouse Educational Foundation Science Talent Search group, a Science Service organization.[8][verification needed] The paper entry was named in the "Honors Group" publicized to universities on January 25, 1978.[9] The paper was subsequently invited and presented at the Iowa Academy of Science at the University of Northern Iowa.[10][11] The operational prototype was displayed at the Eastern Iowa SEF[12] on March 18 and obtained a top "Physical Sciences" award and IEEE recognition. The project was again displayed at the 29th International SEF at Anaheim Ca. Convention Center on May 8–10.[13] The ¼-inch thin miniature flat panel modular prototype, scientific paper, and full screen (tiled LED matrix) schematic with video interface was displayed at this event.[14][15] It received awards by NASA[16] and General Motors Corporation.[17][18][19] This project marked some of the earliest progress towards the replacement of the 70+-year-old high-voltage analog CRT system (cathode-ray tube technology) with a digital x-y scanned LED matrix driven with an NTSC television RF video format. Mitchell's paper and operational prototype projected the future replacement of CRTs and included foreseen applications to battery operated devices due to the advantages of low power consumption. Displacement of the electromagnetic scan systems included the removal of inductive deflection, electron beam and color convergence circuits and has been a significant achievement. The unique properties of the light-emitting diode as an emissive device simplify matrix scanning complexity and have helped the modern television adapt to digital communications and shrink into its current thin form factor.
The 1977 model was monochromatic by design.
Recent developments
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MicroLED displays are currently under development by numerous major corporations such as Sony, Apple, Samsung, and LG.
These displays are easily scalable, and offer a more streamlined production process. However, production costs remains a limiting factor.[20]
The 40m large LED display at the Armin Only event in April 2008 in the Jaarbeurs UtrechtSee also
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References
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When you’re in the market for a big, bright screen, it’s important to understand what you’re buying before you invest. If you’re starting with the basics of screen technology and looking for answers on why a modular or mobile LED wall is the best choice, you’ve come to the right place. If you’re ready to dig a little deeper, just reach out! We’re happy to answer any technical or practical questions that come to mind.
LED stands for Light-Emitting Diode. This acronym refers to a technology that allows screens to produce lots of light, with little electricity. Along with the technology of a light-emitting diode comes the specific requirements like power adapters, or drivers that assist in regulating voltage. The technology is extremely durable. In the early 90s, it was advanced to include red, green, and blue colored lights, which were developed into what we now use in LED screens.
LED displays are flat-panel displays that use individual light-emitting diodes (LEDs) as pixels to create images on a screen. The diodes (that’s the “D” in LED) are electricity conductors that, when a voltage is run to them, light up. When varying voltage is applied to each individual LED, they shine at various levels of brightness, creating images. There are multiple types of LED display panel types with differences that make them better for different usages. These types include lightbar, dot matrix, 7-segment, 14-segment and 16-segment.
The first LED display was invented in 1962 by an engineer at General Electric. Due to technical limitations of the time, it could only produce monochrome red images. Despite continuous development over the decades, full-color LED screens weren’t available until the late 1980s. You might remember from early science lessons that incandescent light, you know Edison, is a result of a heated filament. Well, the light produced by an LED is actually considered cold light because it is generated within the diode itself. This is a much more effective and efficient way to produce light.
LED is the best choice for a variety of screens for multiple reasons. First, LED is extremely energy-efficient. Its low energy consumption makes it ideal for rechargeable handheld devices like phones, tablets, and laptops. Second, LEDs can be arranged in very dense arrays (thousands of cells very close together), which means they allow for incredibly detailed, crisp static and moving imagery. Third, LED screens produce very bright images, which makes them fantastic for outdoor use and for viewing at a distance. They can be illuminated brightly enough for viewing at night or in bright sunlight.
LED is a type of LCD! LCD stands for liquid crystal display. The crystals are what determine how much illumination is displayed in each pixel (or diode, in the case of LED) at any given time. As a broad category, most LCDs have made way for LEDs. Instead of using CCFLs (cold cathode fluorescent lamps) to illuminate each pixel, most modern LCDs use LED.
Yes, an LED display is worth the investment. When you’re trying to capture the attention of a large crowd, there’s no other display on the market today that’s as bright and captivating. LED displays can be used in almost any weather condition, at any time of day. They don’t consume a lot of electricity to power their high refresh rate and dazzling color. Plus, depending on how often you’re using your LED screen, they can last a very long time.
Internet research can only get you so far. When you’re serious about an LED display screen purchase, reach out to the experts at Insane Impact. With an understanding of your goals and use cases, we can ensure you make the perfect choice of LED display.
Screens are one of those things we all use, but few of us actually understand how they work.
At Insane Impact, LED screens are what we do. We build custom solutions to create unforgettable experiences and it all starts with a little light.
Red, green, and blue (RGB) are the three basic light colors that make up every visible color. LED screens have many red, green, and blue LEDs expertly placed to create the picture you see. Mixing hue (level of color) and saturation (lightness or darkness) those three colors of LEDs make any color and image.
Resolution is a combination of the number of pixels and how close they are together. Here’s how it works. LEDs are grouped in RGB groups. The grouping is called a pixel. The distance between pixels is called pixel pitch.
Still with me? An average high-definition television will have a resolution of 1920p x 1080p with anywhere between 3mm to 6mm pixel pitch. That means there are 2,073,600 pixels and they are roughly 3-6mm from one another.
However, the further away you are from a screen the fewer pixels and higher pixel pitch you need. That’s the way our eyes work. Looking at a MAX 2313, our 23 ft by13 ft screen, is a lot different for our eyes to take in than 72 in television. You view a television anywhere from 10 ft to 30 ft away, but you’d view a 23 ft screen across a football field. It makes a higher resolution unnecessary because your eyes won’t really be able to tell the difference at a distance.
The next functional component of a screen is called NITS. Nits measure the brightness of the screen. You can have all the pixels as close together as possible, but if you don’t have the proper brightness you won’t be able to see them. When it comes to brightness, the brighter the space you are viewing the greater NITS needed. We recommend a minimum of 5000 NITS for viewing in direct sunlight.
All of the functional components of your screen are only of value if your content is designed for it. For example, you wouldn’t try to view a 4k blu-ray on a high-definition screen. The resolution of the content is too much for the screen. The best viewing experience is when the content is designed to be compatible with the way it is being displayed.
Did you know graphic designers and photographers use different color types depending on how it will be viewed? They actually design in RGB for digital content so that it will appear properly on an LED screen.
It’s our job to help you create a display that will connect you with your audience. Give one of our representatives a call and we’ll get started.