EDITORS CHOICE 12.01.18

LED displays: Moving in

LED main image
LED display in hotel lobby

As LED tiles move indoors, Hurrairah bin Sohail speaks with manufacturers to determine what made the shift possible and what steps are being taken to refi ne LED tiles for indoor applications.

LED tiles for use in indoor videowalls are rising in popularity. Steve Scorse from Unilumin gives a quick history lesson: “The fi rst 4mm pixel pitch LED walls were introduced less than ten years ago. Those were only suitable for extremely large indoor displays, and due to costs were limited to iconic projects. The 2.6mm and 1.9mm pixel pitch indoor LED walls really triggered the demand growth starting in 2012 and 2013 and as pixel pitch options have continued to get smaller, so have the respective costs. Today, any auditorium or indoor public space must consider LED as the prime option for large venue display, be that for branding, presentation or retail and signage.”

Steve Seminario, vice president of product management at Leyard and Planar, says: “Indoor LED videowalls create a seamless display surface of any size, so they are very flexible in terms of maximising visual impact in any room.”

Glenn Bailey, vice president APAC at SiliconCore, adds: “With the growth of finer pitch LED products in the AV display market in general, we have seen a rise in popularity of indoor videowalls being used in places like hotels and retail where traditionally only an LCD display may have been afforded. It is also the architectural drive from clients to have bigger and better that has made seamless LED products the only real practical option for larger scale displays.”

Dan Chase, vice president of APAC at Daktronics, says: “LED videowalls offer several advantages over other technologies. They are more durable, require less energy, have a longer lifespan, and offer size and shape fl exibility that is not easily achieved with other technologies. With LED displays, you can create curves and unique aspect ratios with a seamless design which can transform an environment into an enveloping sensory experience for the audience. We have seen more venues installing LED videowalls in Asia and LED videowalls are becoming standard equipment for new construction and rebranding of existing venues.”

A key technology development that has enabled LED tiles to make the shift indoors is their steadily decreasing pixel pitch.

Seminario from Leyard says: “LED videowall technology for indoor applications has greatly improved in the last several years. Some indoor LED products now support fi ner pixel pitch for closer viewing distances – they are more often designed to exactly hit common content resolutions like full HD and 4K. They support better low brightness grey level performance, can be architected to use less power, and certain models are designed to be mounted more easily and to take less room. The cost of indoor LED displays has also come down substantially making it a viable alternative to LCD in more cases.”

Bailey from SiliconCore says: “Smaller and smaller pixel pitch options have now made it practical to use LED in the growing scenarios that require up close viewing distances. The use of LED now for fi ne detail content presentation and also for the rising popularity of digital art walls provides distinct advantages over the old school LCD wall where seams and uneven ageing of screens makes it less desirable for use.”

Chase from Daktronics talks about other factors which have also helped the cause: “The increase in popularity of LED is largely due to the reduction in cost. New technologies can be built at a more competitive price which has made them a direct competitor to LCD now. There is a range of quality levels with LED displays, but a high quality display made by a reputable company offers several advantages over LCD. LCD displays are typically limited to a 16:9 aspect ratio, whereas LED modules can be used to fill any space, regardless of the aspect ratio. LCD videowalls have always been subject to the distracting seams and bezels that break up the image and detract from the experience, LED panels are seamless and provide a complete sensory experience for graphics that span across the entire videowall.”

While the pixel pitch of LED tiles has reached below 1mm, manufacturers believe that it will continue to go down.

Scorse from Unilumin says: “We have still not arrived at the smallest pixel pitch for every application. Certainly today’s 0.9mm pixel pitch LED display, with a close viewing distance of below 1mm, can cope with any of today’s common applications. However, smaller pixel pitches of 0.5mm to 0.8mm will become available and will start to drive LED applications for smaller and interactive LED displays in simulation, visualisation, residential and other closer viewing requirements.” Others believe that further reduction in pixel pitch will come at a price.

Chase from Daktronics says: “There is likely still some room to decrease the pixel pitch of LED technologies, however reduction in pixel pitch offers several challenges. First, the smaller the pixel pitch the more delicate the product becomes, which can cause an increase in failures. It is also important to note that displays with extremely tight pixel pitches have a much higher density of electronic components which can cause a signifi cant rise in operating temperature, which is the leading cause of LED failure. As pixel pitch drops, the importance of engineering appropriate heat management increases exponentially. I believe that less than 0.5mm will be the standard tightest NPP after some time. Indications from the industry looks like Micro LED will be competing in the same market as less than 0.5mm. Chip on board should make 0.5mm LED tiles affordable.”

Chase raises an important point regarding operating temperatures. For integrators using LED tiles used for indoor videowalls heat dissipation is a consideration. The nearly 360-degree LED videowall in the main ballroom of the St. Regis hotel in Kuala Lumpur, deployed by integrator AFS Engineering, required its own dedicated air-conditioning system to be included as part of the HVAC system to keep internal temperatures down. That may not however be a feasible plan of action for all projects.

Seminario from Leyard gives integrators some advice: “The fi rst step integrators can take is to select products that are designed for low energy output. Leyard and Planar’s latest fi ne pitch LED lines all share an architecture that consumes signifi cantly less power at the same brightness levels. Another factor to consider is the reflectivity of the LED display itself. Displays that are less reflective and have darker black levels can compete with ambient room brightness with their low reflectivity rather than having to count on increased brightness only. Two other considerations include maximum brightness level settings and content selection – setting the display only has high as you need, and understanding that pure white consumes the most energy and generates the most heat.”

Bailey from SiliconCore says: “Power consumption and heatload are still the major factors that should be addressed in selecting high resolution fine pixel pitch videowalls. The increased demand for large scale walls of high resolution, requires the products to have very high packing densities of components and this is where new technology initiatives are required to be successful. SiliconCore with its Common Cathode technology has continually been addressing this by focussing on providing technology initiatives in the design of the LED driver chips. The latest ZACH driver chip range is addressing the need now for High Dynamic Range requirements where LED not only needs to provide high brightness and bold colour capabilities but detail in content especially in darker level video content.”

Chase from Daktronics adds: “The primary responsibility falls on manufacturers to design electronic components that manage and dissipate heat combined with ventilation and circulation systems that dissipate the heat and keep the overall display operating within optimal parameters to extend the displays life and improve the visual quality as the display ages.”

In the coming years, LED tile manufacturers believe that their product will continue to become suitable for more and more indoor applications. Scorse from Unilumin says: “While new, even smaller, pixel pitches will introduce LED videowalls to certain new markets, many other factors will aid the growth of indoor LED in existing markets. New generation LED displays will become thinner, lighter, lower power and more plug-and-play as advances in modularity, tile-to-tile connectivity, communications protocols, and new materials take effect.”

Chase from Daktronics says: “LED videowalls will continue to be a growing market. Having this equipment installed in facilities is becoming the norm in retail, casinos, sporting and the hospitality verticals throughout Asia Pacific. Low cost and chip-on-board offering easier maintenance and more robust, smoother surfaces will help drive this demand.”