How do liquid crystal displays (LCDs) work?
Asked by: Brian Mitchell Answer In liquid crystal displays (LCDs), use is made of linear polarisers, familiar to most as the glass in polarising sunglasses. If you “cross” two polarisers (i.e. arrange them at 90 degrees to each other) then light does not pass through. This is the basis of the LCD, but between the cross polars the liquid crystals are arranged with a “twist”. This twist allows light to pass through. However, when an electric field is passed through the liquid crystals, the twist is removed, and so light cannot pass through – the area appears black. For more info on liquid crystals, see my previous answer at: http://www.physlink.com/Education/AskExperts/ae303.cfm Answered by: Jan Skakle, Ph.D., Lecturer, University of Aberdeen, Scotland, UK If you’ve ever played with polarized sunglasses (or polarized plates in physics class), and noticed that when you have two polarized lenses rotated at the right angle, you know the basic idea behind Liquid Crystal Displays (LCDs). An L
