🚀 go-pugleaf

In article <5486@boulder.Colorado.EDU>, hassell@tramp (Christopher Hassell) writes:
>I have heard about a VERY interesting though likely to fail new method of 
>3-d displays.  It basically is like a crt except that a mirror *vibrates*
>at 60hz (probably audible) back and forth, producing a "scanned" block
>of apparent display space left on the retina.  I would be cheap, but the
>moving part aspect will probably kill it.

Not at all.  You have described the BBN Spacegraph.  It is not new at
all; maybe almost 10 years old by now.  It is a PC (as in IBM) board
plus a reasonable-performance oscilloscope with very low persistence
phosphors.  A rigid plexi mirror is energized by a good ol' woofer at
60 hz, causing it to change its focus and move the reflected image of
the oscilloscope face through an apparent depth of a few inches.  The
60hz is essentially inaudible (it may be 30 hz; you can paint both
comin' and goin' for an effective 60hz refresh).  The mirrors hold up
just fine.

I can provide a contact if anyone cares.
--
/jr
jr@bbn.com or bbn!jr