• Question: How do touch phones, tablets etc. recognise your touch but not an ordinary objects?

    Asked by to Daren, Lynne, Phillip, Simon on 20 Jun 2014. This question was also asked by .
    • Photo: anon

      anon answered on 20 Jun 2014:

      The surface of the screen is covered by an ITO film (stands for indium tin oxide) which conducts electricity and stores some electrical charge on the surface. Your body conducts electricity and takes some of this charge away from the screen. The phone measures when some of the charge is taken away from the screen and reacts to that.
      If you try touching your phone with a conductive material it works too because the charge goes onto that too. (I just tested this theory with a coke can to check and it does work!)

    • Photo: Lynne Thomas

      Lynne Thomas answered on 25 Jun 2014:

      Jenny has pretty much answered this for you. I always find it annoying in the winter when if I want to use my phone outside, I have to take my gloves off before it will work! This is also why you have to buy a special pen (a stylus) if you want to use the touch screen as a notepad you can write on.

Comments