Everything You Need to Know to Select an Outdoor Rugged Tablet – The Screen

Everything You Need to Know to Select an Outdoor Rugged Tablet – The Screen

If you take a standard laptop outdoors in bright sunlight then the chances are you won’t be able to see much detail on the screen without twisting the device to get as little sunlight interference as possible. This problem makes standard screen devices, such as laptops and mobile phones, impractical for use in an outdoor environment. So how do rugged tablet PCs get around this problem?

There is a measure of brightness called a NIT. A NIT is a luminance unit equal to 1 candle per square metre measured perpendicular to the rays from the source. This scientific explanation does not make a great deal of sense to a layman but it is extremely useful when comparing Geniatech Panel PC devices. To give you a base line to start from, the standard laptop and desktop screen operate at around 200-250 NITs. Standard Rugged tablets for use in industrial settings and warehouses currently come with a 350 NIT screen as standard.

Rugged Tablets that are designed to be used in an outdoor environment can improve the screen readability by either increasing the NIT rating on the screen or by applying a polarising filter to a 350 NIT screen. These two techniques produce readable screen it direct sunlight but both have their own side effects.

By applying a polarised filter to a screen you run the risk of making the device difficult to use with some makes of sunglasses. If you ever did Physics at school you may remember the experiment when you take two polarised lenses and turned one of them so it was at 90 degrees to the first lens. The result of this experiment for those of you who can’t remember that far back, is that light is not allowed through the lenses and you can’t see anything. A good example of this problem can be seen by taking your Iphone (as it has a polarised screen) into a sunglasses shop and seeing the difference different makes of sunglasses make on the brightness of the screen.

So that leaves increasing the NIT rating of the device. To do this you need to increase the backlight in the device and this requires more power and therefore decreases the battery life of the device. Outdoor Rugged screen are now available up to 1200 NITs, these devices can actually be painful to read indoors because they are so bright.

The last thing to consider is the contrast ratio. Although a display with less than 500 nits screen brightness and a mere 2 to 1 contrast ratio can be read in outdoor environments. A true sunlight readable display is normally considered to be an LCD with at least 1000 nits of screen brightness and a contrast ratio greater than 5 to 1.

So when considering which type of screen is the best solution to your outdoor requirements you must weigh up the importance of good battery life with usability. With the use of hot swappable batteries or external power supply it is usually advantageous to opt for a screen with at least 1000 NITs however if these power options are not available a 350 – 500 NIT polarised screen with a good contrast ratio will get the job done.

Leave a comment

Your email address will not be published. Required fields are marked *