Traditionally for outdoor use, LEDs have been the most common display type. This has been because LEDs are brighter than LCD displays so in at night time the screens stand out more – but more importantly the added luminance can counter the effects of the sun during daylight hours.
Daylight and sun glare are a common problem for any outdoor digital signage system. Direct sunlight has the effect of washing the screen out – the light from the sun masking the brightness from the screen. Direct sunlight can also cause glare, reflecting the sun directly off the screen making it impossible to view.
There are ways to counter these problems caused by the sun. Anti-glare glass for instance will mask sun-glare but when it comes to sun readability unless the device is shrouded or angled away from the sun you have to fight brightness with brightness.
Backlit LCD screens and transflective screens
LCDs are now becoming powerful enough to be used in outdoor locations under direct sunlight. Both backlit LCDs, that use LEDs to illuminate the LCD image; and transflective screens that bounce the sun’s own rays back to amplify the brightness of the screen are two up and coming technologies that are allowing LCD displays to be used outdoors.
The secret of these devices is the level of brightness they can muster. A standard LCD device will manage 500-800 nits/candelas in brightness, whilst these high brightness TVS can almost treble that.
However, it must be noted that just because a high brightness screen is capable of coping with the sun, the LCD display can not just be carted outside. Protection against temperature and the weather will also have to be factored in any outdoor digital signage projects – as will anti-vandal protection.
High brightness TVs placed inside and outdoor LCD enclosure is a simple and cost effective method of doing this. A decent high brightness device,. Housed in an enclosure will be protected from all the outdoor elements; temperature, rainfall and impacts whilst being powerful enough to cope with the brightest of sunny days.
