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Over the past 20 years or so, digital screens have really come into their own and the rapid rise of LED technology has revolutionised mass audience communication. The scope for using LED screens is extensive, from small indoor information and presentation units for offices and reception areas, to giant advertising billboards and mobile screens for outdoor events—practically everywhere you go.

In addition, most LCD screens are now being designed with LED back-lighting, instead of traditional fluorescent backlight, which reduces power consumption and allows for a slimmer cabinet depth.

So what are the latest developments in technology in this fast growing market? Thorsten Prsybyl, product line manager, public displays at NEC Display Solutions Europe, comments: “More and more LCD display screens are employing direct LED backlights. The main reason for this is that direct LEDs can be cheaper and suppliers are trying to bring the cost down. The trade-off here is that product depth is reduced.”


He adds: “With regard to LED modules, the LED Pitch is getting finer—the latest record is 0.8mm—which enables super high resolutions. How-ever, the cost is currently prohibitively high, with the square metre pricing equalling that of a small car.”

Perpetual motion

NEC’s LED backlit LCD displays include the E, P, and Spectra View Series of screens. The E Series is a commercial grade LCD display, which offers the performance and appearance of large-screen display for corporate users. It is designed for applications such as reception areas, boardrooms, small conference rooms, and also addresses the display requirements for digital signage in retail and leisure locations.

The P Series is a professional grade large screen display that NEC claims provides industrial strength, round the clock operation for the most demanding digital signage installations. The latest product in the Spectra View range is the SV552 model which offers colour accurate large-format display where reliable, life-size colour-accurate images are an essential requirement.




When it comes to LED displays the company says that products, such as its 15BF1 outdoor screen, are the perfect solution to direct messages for longer distance viewing. The 15mm module is light-weight and designed to meet the requirements of both the rental market and fixed installations.



Bradford based Calibre UK is primarily involved with premium large digital signage—typically direct view LED video walls and also large-scale projection. Key developments of the screens themselves include finer pitches, lower power consumption per pixel, and improved mechanical designs.

“Most people are concentrating on how fine a pixel pitch they can achieve but for digital signage this can be counterproductive and a big mistake,” cautions Calibre UK chairman, Tim Brooksbank.



He continues: “LED is brilliant for signage because its contrast ratio is maintained even in high-ambient light. This is partly due to the high point-source light output of the actual LEDs, but also due to clever mechanical design with black areas between each pixel and well-designed shaders or louvres between rows of LEDs. 

“This maintenance of high contrast, even in high-ambient light conditions, relies on the size of the light source (LED) being small compared with the pixel pitch. So, the space between each LED must be large compared with the size of the actual light source in the LED.”

He concludes: “Very fine pitch LED displays, sub-2mm, no longer have that characteristic. This means their high ambient light performance suffers and the normal inherent advantage of direct-view LED displays for signage is lost. 

“As such the rush for very fine pitch LED displays is misguided in many cases and produces poor viewing performance. Far better to specify the correct display for the job, remembering that the viewer should be at least 1,000 times the distance of the pixel pitch—so a 4mm LED video wall requires a minimum viewing distance of 4m.”

The power behind the throne

However, there is more to it than just the screen itself—it is what goes on behind the screens that can make all the difference.

“Processing, in particular scaling, remains paramount for LED display performance. There’s no point spending hundreds of thousands of dollars, or even several tens of thousands on a fantastic LED video wall, only to ruin the picture performance by using the cheapest scaler you can find, or by scaling in a PC graphics card,” Brooks-bank advises. 

He explains further: “LED video walls inherently need clever scaling as the pixel area of the display is non-standard, being determined by the physical area of the display and the pixel pitch of the LED tiles or panels. This means that a scaler, which is able to scale to any arbitrary resolution with pixel-perfect accuracy, is essential.” 

Brooksbank goes onto warn that most LED video walls have a lower resolution than the source or content material being displayed, so down-scaling performance is also a critical element. Indeed, most general purpose scalers are not optimised for down-scaling but for up-scaling, this is also true of low-cost scalers which purport to support LED video walls.

“Their internal technology and algorithms are not optimal for down-scaling,” emphasises Brooksbank, who adds: “The resulting picture either appears to have soft focus and blurring, or even parts of characters and image content disappearing altogether or flashing on and off as the image moves on the screen. LED video wall scaling is therefore very demanding on the scaler and only LED-optimised scalers, such as Calibre’s LEDView530 and Kramer’s VP-794, can really cope with this properly.”

A perfect example of a large scale LED screen application done right was the use of Calibre’s LEDView scalers to power the giant screens that were used for the recent Tour de France Grand Depart in Yorkshire. With more than five million people lining the roads, relatively few were able to get up close to the action. But they were able to watch on the screens supplied by Lightmedia which ran from Leeds to Harrogate and from York to Sheffield. Big TV’s units were also installed at sites in Skipton, York, and Leeds, with both companies specifying Calibre’s LEDView530.

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Big TV head technician Simon Woodcock explains the reasoning behind the choice: “We provided LED screens to various areas on the opening weekend. The new ‘SkyFly’ mobile LED screen wowed crowds and we also provided screens for a number of private events and parties in Yorkshire as well. Calibre quality is central to our LED fleet for managing live feeds. The LEDView530 can take anything you throw at it.”

Pauline Brooksbank, managing director, Calibre UK responds to this high praise: “As a Yorkshire company ourselves, we were delighted and extremely proud to have supplied LEDView530 units to power so many LED screens along the route of our county’s ‘Grand Départ’. This unforgettable weekend was not just a celebration of cycling but a unique opportunity for local people to experience a sporting event they had never come so close to before.”



Future proofing

With the development of new technologies moving so rapidly this naturally raises the question of sustainability, in particular relating to product life and the potential to up-grade or add on to existing equipment.

 “Professional grade LED and LED backlit technology is extremely reliable with long life cycles; there are no replacement parts such as with projection lamps for instance,” affirms Prsybyl, who adds: “Direct LED backlight technology minimises power consumption, reducing the total cost of ownership from an operational and environmental perspective. But it isn’t possible to upgrade the screen technology, neither modules nor LCDs with LED backlights.

“However, the LCD LED backlit display, in terms of its connectivity and adaptability, is made future proof with the large selection of OPS and Interface extension slots offered in NEC’s large-format LED backlit displays. Intel’s Open Pluggable Specification (OPS), also guarantees flexibility on signage applications by standardising the design and development of digital signage devices and pluggable media players.”

One alternative way of ensuring the sustainability of digital display screens is by incorporating them into new and innovative display solutions. This has been the approach of Elonex with its freestanding retail Peg Board Display, supplied by its One Digital Solutions division. The company offers a complete package from project consultation, product design, network development, and manufacture to software and installation. Sister company One Creative Media also provides integration of traditional print, design, and packaging with the Digital Displays and Nano Screens.



The Peg Board display is a development of Elonex’s freestanding digital kiosks and features rows of 15, 20 and 25 peg holes at various intervals going down the board, which meet the industry standard, as used by major retail outlets. It incorporates a 32" digital screen which comes in both landscape and portrait options.


“Peg Boards are designed to fit multiple peg display and shelf systems,” explains Elonex managing director, Richard Westhead, who adds: “This provides flexibility to accommodate different products and different size magazine and brochure shelves. Because the units are free-standing they can be placed wherever required and do not take up any wall space, which is always at a premium.

“We can also produce bespoke units, such as those that are being rolled out to 75 universities, where a box with a spring-loaded base for holding news-papers has been designed to fit to the peg board element of the unit, below the digital display advertising. They are designed mainly for retail applications but also lend themselves to smaller businesses as they are offered at a reasonable price point.”

Indeed, the 32" screens incorporate an android digital signage player with HDMI and built in Wi-Fi for just such a purpose. They will also operate a range of digital signage applications such as Elonex’s DSA-DS Player Cloud Software, which updates through GooglePlay.

This and the other impressive pieces of technology and their evolution brings to mind a line from the Rubaiyat of Omar Kayyam: ‘The moving finger writes and, having writ, moves on’. This possibly offers a parallel for the relentless push of LED and digital technologies towards ever greater and brighter offerings. Who knows what exciting creative and lucrative avenues they may open up in the future? One thing that is for certain is the sheer pace of development and growing demand for such systems means there is a lot of space in this sector for the canny businessman to exploit.


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