sbw@naucse.UUCP (Steve Wampler) (08/28/87)
I was just talking to an undergrad here who is designing an
architecture to go with an optical base. He as been told
by another professor (who knows much more about this area
than I do) that by using holograms, it should be possible
to build the equivalent of a table lookup for, say,
multiplication (actually, it was explained to me as storing
the algorithm on the hologram - since actually constructing
a multiplication table for two 32-bit numbers is timewise
unfeasible). The upshot is that the multiply could be
done in one cycle, at (nearly) light speeds.
Now, I don't know the first thing about hardware, much less
optical hardware, but that just doesn't seem particularly
reasonable. That's a lot of 64-bit values to store, and
I've always thought holograms had to have a great deal
of redundancy about them. I think I can see storing
an algorithm, but then I can't see the 'single-cycle'
access. I can't conceive of actually storing the table.
Would anyone out there who actually knows something about
all this (I understand that this isn't new, just the resolution)
mind mailing me a layman's overview of how this works (if
a layman's overview is possible)? I'm not particularly interested
in a 'Can Do -- Cannot Do' argument from people like myself
who know little - I would prefer to hear from someone who
as actually looked into this.
As an aside, just how close are we to having optical computers?
This student has been led to believe that he will be able to
produce an optical computer of his own design (using manufacturing
equipment design to produce existing silicon-based circuitry)
very soon (say within 1, at most 2 years). I do not want to
discourage him from trying, if it is feasible, a lot of things
have been done this way, and I like to see students try things,
anyway. However, if he is misinformed about the reality of
it, it is probably something he should at least be aware of.
Sorry to be so long on this.
Please Email any responses, since I don't get comp.arch here.
Thanks!
Steve Wampler
{....!arizona!naucse!sbw}