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scott wrote:
>> Again, my sat nav allows you to scroll like this - but it's very
>> unpredictable. It doesn't "respond" very well to the touches you're
>> trying to make. I don't know why. Also, it's very hard to *slide*
>> warm, sticky fingers over a plastic surface in a smooth motion.
>
> Your satnav is likely a resistive touch screen, it works when you
> physically bend the top layer enough to make contact with the bottom
> layer electrically, and then just like a variable resistor you can
> measure the resistance to work out the position you touched. The iPhone
> uses a capacitive screen, as soon as you touch the surface of the screen
> the electronics can detect the capacitance of your finger, also using
> clever electronics/software it can work out the position of 2 fingers in
> contact, to allow those wacky zoom and rotate operations.
>
> The disadvantage of capacitive touch screens is that they only work with
> your bare fingers, not while you are wearing gloves, or any sort of
> stylus. The accuracy is also much lower than resistive touch screens,
> but that doesn't really matter when you're using your fingers.
Damnit, I wish I knew some people IRL who possess such encyclopedic
knowledge... I'd never be bored again!
[FWIW, the sat nav *does* in fact have a stylus. Unlike my dad's cheap
device, the stylus is optional on mine. On my dad's, only the stylus
will operate it...]
PS. Is it only me who things pointing a sharp pointy thing at a delicate
and fragile layer of semi-liquid gloop fashioned into an intricate
display mechanism is a bad idea?
--
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*
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