[maemo-developers] Nokia - lost second chance - another multitouch by Apple patented

[From: Sarah Newman]

I am 99.99% certain the internet tablets use resistive touch screens, 
which means this underlying technology cannot do multitouch.

Using more than one contact point on these screens will change a 
reading, but it won't get the result you want. It will be an 
intermediate reading between the multiple contact points.

Here is a manual from atmel which seems to do a decent job of explaining 
how a resistive touch screen works:

http://www.atmel.com/dyn/resources/prod_documents/doc8091.pdf

My assumption also is that this is a 4 wire touch screen, not a 5 wire 
touch screen, since we can get pressure readings and 5 wire touch 
screens don't do pressure readings.

For comparison, this is a relatively friendly guide on how one kind of 
capacitive touch screen works:

http://electronics.howstuffworks.com/iphone2.htm

It may not be the only kind of capacitive touch screen.

You might reasonably ask why Nokia chose to use a cheaper and less 
capable technology (digikey.com lists relative pricing and this is how I 
know it is cheaper.)  My suspicion, other than cost, is that they 
already knew how to use resistive touch screens and didn't see a reason 
for adding additional technical or perhaps legal risk.  Or maybe since 
it's so cold in Finland nobody takes off their gloves and everybody uses 
a stylus instead, which you aren't supposed to be able to do with a 
capacitive touchscreen (see above link.)

Darius Jack wrote:
> Hi,
> 
> you said:
> "
>> There is no native multi touch on these devices.
> "
> Who said otherwise ?
> 
> You can call my experience with maemo multitouch side-effect.
> Ok.
> But it works for me.
> I use both iPod Touch and maemo.
> It works how it works but works (side-effect or alike) ;)
> 
> you asked
> "
> have you ever actually done any coding for maemo
> "
> 
> Tried hard to loggin into maemo, 3 times failed and gave up.
> Logging procedure problems.
> __________________________________________________________________
> There is no such facility like Think-Tank at Nokia, so no chance
> to develop and discuss multitouch for Nokia/maemo.
> Moreover, one or more guys from this dev list claimed that discussing
> multitouch for Nokia maemo was spam.
> 
> Wish you success anyway.
> 
> Darius
>