When it comes to outdoor digital displays there are currently three main contenders: LED, LCD, ePaper. The following is a brief comparison table of the main characteristics of each. Each technology has its advantages depending on the targeted application. Cost is a huge variable with each of these so very hard to provide a direct comparison, in any case, the characteristics of each technology are the main differentiator.
|Resolution||Medium to low, good for large displays viewed from further back. Dot pitches are typically 2mm or larger||High resolution. Typically around 0.4mm dot pitch.||Very high resolution at <0.3mm.|
|Brightness||High brightness. Typically around 5,000nits||Medium to high. Most high bright LCD are from >1,000nit to around 3,000nits. Some up to 5,000nits.||Reflective & sunlight readable. Nightviewing options with lighting.|
|Power||Requires mains power||Requires mains power||Can run off solar or wind with a battery|
|Size||Medium to large, 65″ and larger, up to very large.||Small to medium, up to 86″ without tiling. Tiled displays have bezel lines.||Up to 42″ without tiling but scalable with tiling.|
|Color||Full color||Full color||Monochrome|
LED is the clear and prevalent favorite for large sports arena displays and billboards. The ability to create a display of almost any size and good daylight readable brightness that can be turned down for night viewing makes it the clear choice for certain installations. Although LED is achieving ever higher resolutions in indoor displays, high-resolution LED doesn’t have the brightness for outdoor viewing at this time (April 2021).
LCD stands out when color and resolution are needed in an outdoor setting, a good example is for drive-thru QSR menu boards. It is ideally suited for small, eg kiosk sized displays where color and maybe video is wanted, medium size such as advertising displays, and up to around 86″ diagonal display size. Resolution is excellent making it suitable for close to medium distance viewing. Digital View has been supporting LCD for over 25 years and has controller boards in many outdoor installations, in particular, there is the range of models for harsher environments as summarized in the Harsher Environment section here: https://www.digitalview.com/controllers/lcd-controllers-home.html
E-Paper has a unique niche with ultra-low power requirements and excellent sunlight readability. An e-paper display doesn’t require power to hold an image and only uses a small amount of power to change the image. This makes it ideally suited to being powered from solar or wind with a battery as a power buffer. As it is reflective, e-paper is less obtrusive than LED or LCD and therefore ideal for public signboards and places where light emissive displays are not wanted.
The main ePaper solution on the market is from E Ink. Digital View supports their panels with the EPM-100 for 32″ and 42″ panels and upcoming EPM-050 driver boards for 13.3″ panels. See https://www.digitalview.com/controllers/epm-100-eink-interface.html
There are other outdoor digitally controlled display technologies such as certain types of electromechanical displays but they are becoming less common compared to LED, LCD and ePaper.