Love the community and very interested in multi touch, although lacking a background in math, physics and programming I am not technically inclined in this area. 

However, I do have a question I was hoping one of you might be able to address for me. 

The essence of Han’s and Microsoft’s designs are the us of IR cameras to pick up the action, which as far as I am concerned is the limiting factor in terms of display placement.

The camera has to be physically distant from the surface to register touches.  Why not make the surface the IR camera and the IR emitter??

My very basic understanding of quantum dots is that you can tune their emission and resorption spectrum to specific wave lengths even IR.  Add that to the fact that a process exits to apply the dots cheaply and transparently, I think, (as I said I am no expert), to very large surfaces, houses even, you have the two basic properties of the multitouch display in nano form?

Check out Prof. Ted Sargent’s work at http://light.utoronto.ca/index-research.html
And let me know what you think.

Is this actually possible or is there a degree of complexity that I am missing?? 

Just thoughts sorry if this has all been covered before.

Thanks for your help

from having a quick look at that site, its still being researched?

this could be a viable way of doing multi touch, although the dots would have to be on a different surface so as not to interfere with the FTIR effect (just add another layer underneath the acrylic)! if it was available it would be perfect, in that you could just mount the mtouch panel infront of an existing display!

but all that said, ive no idea on how you would interface with the quantom dots, and the blob detection would need to be redesignd for sure!

nice find though! wonder how long b4 they mass produce it!

Well, maybe this is too optimistic. I don’t think we’ll see any of this in the near future, and certanly not at my hardware store here in SouthAmerica.
Well, it seems also that you dont need ir lights or cameras, since this dots are semiconductors, they are light sensitive already (every semiconductor has a reaction to light) so, a film of this quantum dots (reminds me of “Quantum leap") could be a multitouch film, so you could read it reaction to touch and even a “hand near” kind of interaction.
But again, i guess my child (2 years old) could build his first MT table with this, near 2050?

Well you can buy quantum dots for example: Scroll down and you can order! But I don’t know if 50 mg is enough? Cuz I don’t even know this stuff

http://www.evidenttech.com/products/evidots.html

But I would like to know the process. I am wonder if you really need a conductor then should ITO coating which is transparent, and IS currently being used at least I know they use them in LCD’s and somehow get the same effect?

I am extremely interested in making an “overlay” screen that can make any display into mT, so I was wondering if ITO could be used this way. The closest I came to know is that they are used in digital matrix displays, I read it off of the building of the Lemur multitouch screens. If a semiconductor such as ITO could have a circuit where each grid point could be “recognized” then it would be easy, but getting an transparent circuit is the hard part. I read that Oregon university found something but hell they didn’t release crap. But if there is a way to make a transparent circuit then all that would need to be done is that you take the ITO and their intersection “dot” and link it to the circuit, and then you should be able to recognize all the “intersection” dots, so if you make the grid small enough then you have an extremely effective mT, this idea is something similar to the unMouse of Microsoft, the difference is that they use FSR (pressure) and it is not transparent but the underlying idea is the same: make the whole thing a circuit! And then you have unlimited touches!

Well, what do you know, it is for sale.
but there is a gotcha:
All orders must come from either a corporate, university or government laboratory (blah blah blah)

Again, this is not a finished product, you can’t build a overlay, unless you have the money and research capabilities.