email was Mac something something

From: Tom Jennings <tomj_at_wps.com>
Date: Thu Jan 13 16:19:40 2005

On Thu, 13 Jan 2005, Ron Hudson wrote:

>>> I don't suppose anyone ever manufactured a laser-based paper tape punch?
>>> Is that even feasible?


> OOH A new kind of media: clear mylar tape with a thin layer of paper on one
> side
> (black paper for enhanced absorption ) 16 bit wide? 32 bit wide?
>
> How would mylar and paper be for longevity. How are our oldest paper tapes
> doing?

Oh, now this thread I like!

Paper and mylar longevity is very good. Good old fiche has a
projected 500 year life. Paper can last a long time but machine
handling criteria is different than for books.

A thin mylar strip, say standard 1" wide, with an optical reader
you wouldn't need to make holes, only dark spots.

Use a laser whose output the tape isn't transparent to; a "1" is a
heat-distorted/discolored spot. A smaller spot for the "sprocket"
hole/index.

The smaller sprocket hole provides sufficient lead on a
read-strobe pulse inherently on paper tape, same would go for
this.

Write speed would be limited by energy put onto the tape and fast
enough to avoid blurring the spot due to motion.
Received on Thu Jan 13 2005 - 16:19:40 GMT