In the lead up to our series on teaching touchscreen use, we need a quick exploration of the difference between capacitive and resistive screens. I wanted to keep this separate from the first post, as you’re likely only reading this if you need to understand it better. (If you already have a technical knowledge, this may seem over-simplified – it is, on purpose!)
If you don’t want to read further, but want to know why this is important, here are your two take home points first:
1) Pressing ‘harder’ will not cause a capacitive tablet to respond differently – gentle, but purposeful is best.
2) Capacitive screens can respond to multiple taps at once – which makes them more likely to respond to accidental touches – especially from other fingers or the side of your hand. (This feature will be useful later on – when we talk about pinch and zoom).
Now a bit more detail…
A capacitive touch screen is the type of screen you’ll find on iDevices (iPads, iPhones, iPods) and most Android tablets. Contrary to a resistive tablet, which relies on pressure on the screen to operate, capacitive screens rely on surface area used when touching.
Most resistive screens use multiple layers of material which cause a response when they are pushed together. You’ve probably used this type of screen at movie theatres, airports and mall directories. They only respond to certain amounts of pressure – so you often find yourself having to push ‘harder’ to activate them.
Capacitive screens are different. The capacitive layer holds an electrical charge, which is altered by contact with skin or a stylus tip. The screen is able to record location and size of the input – so you don’t have to press ‘hard’ to get a response – you only need to make sure the input is correct. As a result, you’ll notice it won’t work with gloves on, nor with a pen tip – these are not the right surface to alter the electrical charge. Capacitive screens can also respond to multiple inputs as well – and this becomes useful for certain gestures the iPad and other tablets use for more advanced operation.
I hope this helps with your understanding a bit – and if it doesn’t – just head back to those first two take home points, and you should be good to go!