Photos courtesy Diopso
By David Dumouchel
Outdoor digital signage systems are not very common yet in North America, but they are currently
all the rage in Europe, as the technology has matured enough that they can be deployed in all sorts of environmental conditions and connect with wireless communications networks. They can offer sophisticated interactivity, wireless-fidelity (Wi-Fi) hot spots and wayfinding services.
Consider this scenario: a tourist visits Montreal for the first time and, while approaching his hotel in a taxi, realizes he has forgotten to bring along his travel guide to the city. Fortunately, just outside the hotel, he sees a digital ‘totem’—a street furniture component that displays information in a public area—and approaches it for further information. A touch screen features a map, including the main tourist attractions and shopping centres nearby. Instructions show how to download this map to his smartphone, thanks to an integrated computer. Other content includes listings of nearby restaurants, classified according to the style of their cuisine, and ads for local businesses, updated in real time. The tourist can buy and print a ticket for a live show that very evening.
All of the technology behind such an ‘information hub’ scenario already exists. And a network of totems can be linked to a single control centre and managed by just one or two employees, allowing the city to easily communicate with the public. Interactivity and live update capabilities, in particular, make these systems attractive for public officials and businesses alike.
From static to digital to dynamic
Today, most street furniture in North America is static and requires a lot of time and effort to update. There is
a major opportunity, everywhere from tourist areas to sports venues to transit stations to commercial centres, to evolve to the next generation of outdoor signage and join other media in the shift from static to dynamic, two-way communications.
Even in parts of Europe where sophisticated, interactive digital totems have become ubiquitous, their capabilities are only just starting to be harnessed. They still have plenty of potential, in an increasingly interconnected world, to change the way businesses and other organizations communicate with locals and visitors.
Interactive digital totems have become common in Europe, even in very cold climates.
It is not merely a matter of establishing two-way communications to generate feedback from passersby. Mobile phones could interact with totems for security purposes, for example, and with ‘emotional reading’ software now in development, digital signs could even be used to detect distressed individuals for safety purposes.
Before moving on to such advanced purposes, however, outdoor totems have had to contend with a number of disadvantages compared to more well-established indoor digital signage networks.
Heating and solar issues
For a long time, the biggest problem facing outdoor digital signage has been the need to withstand ambient environmental threats that can be destructive to electronic devices. Consumers can appreciate this need with regard to their own personal mobile phones; water, humidity, dust and snow can all have negative impacts on these devices and it can certainly be a struggle to read and use their screens in direct sunlight. The struggle is compounded for digital signage because outdoor deployments often must operate all day, every day, for years, making the chances of success much slimmer. A series of engineering challenges must be dealt with to ensure effectiveness and reliability.
The two biggest issues are connected by way of the sun: readability and thermal management. Not only does sunlight make readability difficult, but the associated heat is also a pressing threat, as black spots can appear on a liquid crystal display (LCD) screen when its surface temperature exceeds specified limits, leaving portions of the screen completely obscured. Constant overheating can also cause integrated electronic components to degrade extremely quickly, shortening their useful life. Moving toward the operational bounds of digital signage systems will generally cause reductions in brightness and response time; going beyond those bounds can result in permanent damage.
Sunlight is possibly the biggest threat, as it causes issues for both readability and thermal management.
In fact, most problems and disappointments encountered in the past with outdoor digital signage systems have been related to inadequate thermal regulation technologies integrated with LCDs. Everything looks fine at first, but after the first few months, overheating has left the screen unreadable, turning the whole unit into expensive, useless street furniture.
A relatively small difference in inner temperature can mean the difference between a readable screen and an unusable device. It is thus crucial to maintain stable inner temperatures, both to ensure performance and to protect the initial investment.
Damaging heat, in this context, is primarily generated from three sources: solar radiation (particularly dangerous with low-horizon sunlight), ambient air temperature and the digital signage system’s own integrated panel and electronics. Unless highly rugged electronics are specified for the panel and components, these systems are not designed to operate effectively when their internal temperature exceeds 50 C (122 F). This may sound extremely high in Canada, but it is not; the inside of a car can easily reach such temperatures in the summer.
Indeed, someone sitting in a hot car in the summer will need to open the windows and turn on the air conditioning (AC). As it turns out, that is exactly what’s needed for outdoor digital signage systems, too.
A digital signage system’s integrated electronic components should be (a) hermetically sealed to prevent any water and dust from reaching them and (b) kept at stable inner temperatures to ensure their efficient operation. These needs suggest implementing an independent heating, ventilation and air conditioning (HVAC) system, as anything less will impede the whole unit’s performance and durability.
