Posted by: Richard Williams | Posted on: | 0 Comments
While most people recognize an outdoor screen needs waterproofing and protecting from the elements, one aspect to outdoor digital signage protection that often gets overlooked is protection from the sun.
The sun can cause several problems for an outdoor screen and dealing with these issues is not simple.
One of the most common problems caused by the sun on an outdoor digital signage screen is the problem of its brightness. A screen’s brightness often has to compete against the sun and quite often is not powerful enough. On a bright, sunny day, the sun’s brightness can make a screen unreadable, washing out the image and making it impossible to see.
The problem is caused by the brightness level of most LCD or plasma screens. Measured in units known as nits, most LCD screens used around the home and in indoor locations have a nit level of around 500. For an outdoor environment, this level is not sufficient to allow the screen to be read in bright sunlight. High brightness screens with nit values of 12-1500 are far better suited for outdoor environments. The brightness level of high brightness screens is usually sufficient to counter the effects of the sun, ensuring the screed is still readable regardless of how bright the sun is.
Another problem caused by the sun is sunglare. The reflective surface of a screen face can often lead to a reflection that makes the screen unreadable. Sun glare is also far more difficult to correct than the problems caused by the sun’s brightness.
The only measure that can really solve this problem is the use of an anti-reflective filter over the screen face. However, these filters also diminish the brightness of the screen so it’s imperative that when using an anti-reflective filter, a high brightness screen is used.
Another problem, albeit a less common one, is caused when the screen is direct alignment with the path of the sun causing the sun’s rays to bear down on the screen for prolonged periods.
This prolonged exposure can lead to hot spots developing on the screen face, which in turn can cause permanent burn marks to appear on the screen face.
Again, solving the problem is not simple. Of course, the screen can always be positioned away from the path of the sun—this will reduce glare and problems with brightness too—but this is not always possible.
Another method is to ensure the screen is continually kept cool with a stream of air blowing across the screen face; this will prevent the hotspots developing and prevent screen burn.