[sdiy] New toy

[johnspeth at yahoo.com]

> > This thing looks exactly like what I had in mind for a patch 
> > matrix (except the one in my mind had red switches).  Is it 
> > possible to buy switches like that?
> 
> Almost certainly not possible, yet. I recall reading somewhere that the
> Tenori-on is only kinda-sorta mass-produced, i.e. there's a lot of hand
> assembly involved for a contemporary commercial electronic gadget. I'm
> fairly sure that I also read that the switches are custom.

It looks like the Tenori-on could be the manufactured realization of an LED based input device described by Jonathan Pak at:

http://nime.org/2006/proc/nime2006_342.pdf

Basically, the LED is a reasonably good light measurement device when it's reversed biased.  The discharge rate is a function of light and can be measured easily and cheaply using something like a microcontroller.  You get a bonus feature that the LED can be lit up when it's forward biased.  With clever time multiplexing, you can have a cheap input AND output device all in the same package.  

Electronic Design magazine has had a few Ideas for Design articles on the LEDs in that application.  The most recent one was:

http://electronicdesign.com/Articles/ArticleID/15980/15980.html

It's not a mechanical switch but rather an optical measurement device.  In fact, it's not even a switch.

JJS