[net.graphics] Looking for high resolution, portable, penlike input device

gnu@hoptoad.UUCP (10/28/86)

I am interested in finding a technology for sensing graphic input
that is as easy to use as a pencil or pen.  Ideal attributes:

     *	pressure sensitive such that it doesn't draw unless
	you "hold it against the paper".  Best would be able
	to sense how much pressure, so that harder strokes
	could produce darker or wider images.

     *	transparent so that it can be placed over a screen

     *	high resolution, equivalent to or better than screen res,
	100 dots/inch or more

     *	portable, e.g. smaller than a breadbox

     *	input device does not make any permanent marks itself,
	so the computer has full flexibility in redisplaying
	the entered information, putting up new menus or windows
	underneath where the user was entering, etc.

Tablets seem to be OK except for transparency, which is vital
if you want it to act like a pencil.  None of the various touch-screen
thingies I've heard of have better resolution than the size of a fingertip,
and they would be confused by leaning your hand against the surface
(which is quite common when using a pencil).

Blue sky ideas as well as concrete suggestions are welcome, by mail.
I will post the results, if any.
-- 
John Gilmore  {sun,ptsfa,lll-crg,ihnp4}!hoptoad!gnu   jgilmore@lll-crg.arpa
  Overheard at a funeral: "I know this may be an awkward time, but do
  you recall him ever mentioning source code?"		-- Charles Addams