[sdiy] Laser knobs

[Tim Parkhurst]

> -----Original Message-----
> From: Richard Wentk [mailto:richard at skydancer.com]
> Sent: Tuesday, May 04, 2004 6:22 PM
> To: synth-diy at dropmix.xs4all.nl
> Subject: [sdiy] Laser knobs
> 
> At 11:09 04/05/2004 -0700, Tim Parkhurst wrote:
> 
> 
> >On the laser based PDA interface:
> >More info:
> >http://www.palminfocenter.com/view_story.asp?ID=6394
> >This is a device that attaches to your PDA and scans a flat surface with
a
> >diode laser. It looks for interference patterns and can figure out which
key
> >you're pressing on the projected keyboard.
> 
> Is it definitely based on interference patterns? Naively I'd have thought
> you'd get enough position information by timing any back-scattering wrt
> beam location. (Which, so far as I know, is more or less how barcode
> scanners work.)
> 
********************
The interference pattern thing was a bit of a guess on my part (prolly
should have said "I THINK it works on interference patterns"). To tell you
the truth, your theory sounds a lot more likely.
********************

> I'm definitely curious about this item. If anyone has links to patents or
> other relevant details, I'd be very interested.
>
*********************
Maybe look into some of the existing barcode readers and patents for more
info. That might at least be a starting point. 
*********************

Let us know if you dig up anything neat!


Tim (dug up years ago) Servo 

---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.676 / Virus Database: 438 - Release Date: 5/3/2004
 



***************************************************************************
This message is confidential.  The information contained in
this e-mail message is intended only for confidential use of the
recipient(s) named above. If the reader of this message is not the intended
recipient or an agent responsible for delivering it to the intended
recipient, you are hereby notified that you have received this document in
error and that any review, dissemination, distribution, or copying of this
message is strictly prohibited.  If you have received this communication in
error, please notify us immediately by e-mail, and delete the original
message.
***************************************************************************