InfoComm 2016 was again a demonstration in innovation and an implementation of “firsts” in the LED display market; it is these push and pull factors that are driving future change in digital signage.

The innovations this year were unique and seminal for the LED Digital Signage industry.  For example, this was the first time displays were seen for near-to-the-viewer or <2 meters of viewing distance, performance (i.e. tightest pixel pitch) as well as very large area seamless displays which could be found across all of the major suppliers in the industry.  We have demonstrated the ability to prepare displays for the exhibition of 4K (8 million RGB pixels) and even 8K (~32 million pixels) in a single continuous display over 55m2.  It can be said that with LED, anything is now possible in resolution and size.

We have seen that pixel pitch has pushed ahead rapidly in order to allow the HD resolution into ever smaller screen sizes.  For example, High Definition (2K HD) displays at 2.5mm pixel pitch last year occupied 13.8m2 in surface area; whereas prominent throughout InfoComm this year were displays of 1.25mm pixel pitch

However, LED will rarely, if ever outsell the LCD single panel solutions in units; in fact, LCD or emerging OLED single panels, enjoy all the development momentum and growth of the consumer ~$50B TV market.  Visual video performance is stellar on the most critical LCD systems like home theater, with a brightness limitation of ~500 nits which is overcome through upgraded backlights.  When one single display panel is sufficient for the customer for a Digital Signage application, LCD is most often the solution of choice.

The LCD typically supports an “equivalent” pixel pitch of ~0.7mm. UHD or 4K displays which are rarely used in signage but prominent in the consumer TVs seen this year are typically pixel pitches of ~0.35mm.  The fill factor of the LCD TV is greater than that of the seamless tile style LED modular display walls.  Today’s LCD TV supports flat displays with bezels, those black cross-hatch lines found between individual displays when areas larger than 1 m2 are desired. Despite the Very Narrow Bezel solutions of 0.9mm, tiled LCDs have very noticeable black dividing lines that are objectionable if the customer wants a single video display experience.

Considering Resolution and Pixel Pitch

With regard to resolutions, initial thinking might suggest that competitive LED Digital Signage solutions must track LCD and get down to 0.7mm or even 0.35mm pixel pitches in order to be a viable replacement, yet this is simply not true.

  • Based upon size requirements where multiple equivalent LCD panels are the entry point for fine pitch, seamless tiled LED displays with pixel pitches of 1.25mm down to 1.0mm can and will quickly begin to replace needed Digital Signage requirements of resolutions for tiled LCD panel displays. This includes 2×2 (4 panels) and 3×3 (9 panels) or larger.
  • Based upon digital signage sizes and the implied viewing distance plus the ability of the eye to discern the pixels and notice pixilation, a viewing distance of 1.25m-2m can be expected. The Digital Signage system objective is one that the user’s content resolution will match the perception of resolution of the viewer’s eye which is based upon the fovea of the eye and the distance to the screen, to the created resolution of the LED display.
  • Based upon the constraints, the sweet spot for LED seamless tiled displays should focus on the 1.25mm displays starting next year and sustaining that pixel pitch for the next three to four years. Separately in this period there will be many opportunities in the 1.5mm pixel pitch and 1.875 pixel pitch space, but those wider pixel pitches will be new solutions with the larger size and further viewing distance requirements not directly aligned to LCD replacements.

Pixel pitch however, is only one of three factors creating the demand for actions to replace LCD, and provide solutions exceeding its capabilities.  More must be accomplished, and only some in the LED Digital Signage business are addressing these factors.  Other factors include efficacy and visual performance.

Fully satisfying the requirements and capabilities of image quality, efficacy and fine pitch will open the future market to all current and future LCD and projection markets.  Additionally, market growth will also be accelerated in the current state as performance improves.  Pixel pitch is on a path to get tighter.  Along the way opportunities will grow on the 2.5mm and 1.8mm and 1.5mm as the industry focuses on achieving a full value solution in the 1.25mm pixel pitch.  InfoComm 2016 showed the world that anything is possible with LED in today’s market, and we are ready for the exciting innovations ahead. Focusing on pixel pitch, efficacy and visual performance will drive the future of the LED marketplace for true innovation rather than form over function.

~Gary Feather
Chief Technology Officer, Nanolumens