• Question: following on from the question about touch screens, whyy does it work when you touch a DS with a stylus (also for makinse01) xxx

    Asked by hunterlo01 to Carol, John, Philip on 5 Jul 2012.
    • Photo: John Welford

      John Welford answered on 5 Jul 2012:

      Hi hunterlo01 and makinse01

      Touchscreens can work in a few different ways:

      “Resistive” touchscreens connect a circuit within the screen when there is pressure on it.
      “Capacitive” touchscreens use the fact that the body is an electrical conductor (so you can’t use these with gloves on!).
      “Surface acoustic wave” touchscreens send tiny waves over the screen that your finger interrupts (so dirt on the screen can make a big difference to these).
      “Infrared” touchscreens send beams of light across the screen that are interrupted by your finger.
      “Optical imaging” touchscreens use a set of cameras around the screen to look for the shadow of your finger.

      The most common types used in mobile phones and other similar devices are “Resistive” touchscreens (used my most manufacturers) and “Capacitive” touchscreens (used by Apple and a few others). There are pro’s and con’s to to each type of technology.

      Because resistive touchscreens rely on pressure, you can operate them with just about anything. Capacitive screens need a special stylus that is conductive in the same way as a finger.

      As the Nintendo DS has a resistive touchscreen you can use pretty much anything as a stylus!

      I hope that answers your question!?

    • Photo: Carol White

      Carol White answered on 6 Jul 2012:

      With the DS – it’s the pressure that makes it work.

      So imagine ringing a door bell… (trust me on this one…):
      When you press the button you make two bits of metal touch which then means an electric current can flow and the bell rings.

      Some (as John amazingly explained, thank you John!) touch screens have two layers which act like these electrical contacts in the door bell.

      If you touch the top layer of the screen with your finger, you forcer the the two layers touch – and get an electrical current at exactly that point.

      In these pressure-responsive screens you could touch it with anything.. a stylus, your finger, or even a twig!

    • Photo: Philip Glasson

      Philip Glasson answered on 6 Jul 2012:

      Pros and Cons
      “Resistive” touchscreens are more accurate but you have to PUSH !
      “Capacitive” touchscreens are easier to use “with a swish of your hand” but your finger has to TOUCH it, you can’t use gloves !! and it doesn’t work when your fingers are cold !!

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