Looking Inside: The Touchscreen

Last week we launched the latest of our DIY kits, the Computer Kit Touch. And ever since then lots of you (and all of us here at Kano HQ), have been getting your hands on them. Touching the pieces. Touching the Code. Touching the Keys. Creating, and coding art, music, and games of your very own.

Awesome stuff.

But how does it work? How does the Computer Kit Touch stay alive when it’s not plugged in? How does touching the screen make stuff happen? And how do the keyboard and trackpad control code, music and art when they aren’t attached to the computer?

So many questions.

But fear not! Over the next few weeks, we'll be doing our best to answer them as we take a look inside the Computer Kit Touch.

This week we're talking touchscreens, finding out how they work, and taking a look at the components that make up the touchscreen in your Computer Kit Touch.

Since a touchscreen is an LCD screen with some extra features layered on top, lets start at the beginning, and take a look at an LCD computer screen (as found in the Screen Kit, and the Computer Kit Complete) and the components it's made of.

The Kano Computer Kit Complete has an LCD Screen

The LCD screen is constructed of three main components, layered together like a sandwich: with an LCD as the filling in the middle, and the glass, and driver boards either side of it like slices of bread.

But what do they do?

  • The Glass is the part of the screen that you can touch, and when you do, it probably gets a bit smudged with your finger prints. It's there to protect the LCD (which is quite delicate!), and your eyes, by reducing glare.

  • The LCD is the part of the screen which displays images, so you can see the code, art, music, and games that you have created.

  • The Driver Board is the part of the screen that takes data from the computer, and converts it into the images you see on the screen.

Now that we know what goes into the LCD screen, let's move on to the touchscreen.

The Computer Kit Touch has an LCD touchscreen

We're going to be looking at the most common type of touchscreen, found in mobile phones, tablets, and the Computer Kit Touch - this is called a Capacitive Touch Screen.

The construction of the touchscreen follows the same sandwich structure as the LCD screen, and has the same filling (the LCD), but two different types of bread!

Let's take a look at the ingredients in this touchscreen sandwich:

  • This is the Digitizer Glass, which as well as protecting the LCD from damage, and your eyes from glare, also allows you to control your computer with your finger.

  • This is the LCD, which displays images, so you can see the code, art, music, and games that you have created.

  • These are the Driver Boards (mounted to the back on the LCD). There are more driver boards on the touchscreen than you would find on the LCD screen. Their job is to translate the data from the digitizer into actions on screen.

The big difference between the LCD screen and the touchscreen is that the LCD screen is an output device, and the touchscreen is two devices in one, both an input, and an output!

So now we know what a touchscreen is, and what it's made of, let's find out how it works, with the help of Greg Foot at BBC Earth Lab.

Fantastic stuff - Thanks Greg!

If you want to get your hands on a touchscreen computer of your very own, and use your fingers to create art, make music and remix code head on over to the Kano Shop now!

Much Love!

Chris