The advantages of wearing polarised sunglasses is well documented, but there can sometimes be issues reading TFT displays with polarised lenses. TFT displays output light which is inherently polarised in one plane. If this plane is 90 degrees out of sync with the wearer’s lenses, it can make displays all but unreadable, leaving the screen virtually black to the observer. This can be especially important when standard landscape displays are used in portrait mode.
