LASERS! && Freemont Street LED array (was Re: Cray J932SE (was Re: Straight 8 up on Ebay just now))

Wayne Sudol wsudol at
Tue Jul 19 15:58:00 CDT 2016

Laser technology to draw things like this is used in photo typesetters. A
laser beam is focused onto a thin (about 1/2" thick)  many sided (about 8
sides i think) spinning mirror. Each facet of the mirror is cut differently
to deflict the beam up, down or center it on a sheet of moving paper or a
plate of sensitized aluminum. The more facets you have, the more 'cuts' you
can have and the beam can be deflicted more each time it hits the mirror.
The electronics is mainly used to control the timing/pulsing/power of the
laser beam hitting the mirror.  Using the same idea, a larger mirror could
be used to deflict the beam more and shine it on any surface.

 Think of the scene  in the Val Kilmer movie "Real Genius" where they
advertise a part using a laser beam.

Wayne Sudol
Riverside Press-Enterprise
A Digital First Media Newspaper

On Tue, Jul 19, 2016 at 1:45 PM, jim stephens <jwsmail at> wrote:

> On 7/19/2016 1:22 PM, Noel Chiappa wrote:
>> Those have been around for decades - I recall seeing them used to draw
>> things
>> on the sides of building,_many_  moons ago.
> I know that the pen motors from Brush recorders were used eons ago. They
> have frequency response that is very high, and if you had the power to
> drive them would move very quickly.
> Also Oscilligraph motors could be used, and already had mirrors mounted on
> the end.
> Piezo actuators could be mounted on the Brush motors and swung for a
> second degree of motion as well.
> These were in use in the 70's if not earlier.
> Thanks
> Jim
> Gould Brush example:
> GOULD-BRUSH-220-Strip-Chart-Recorder-Model-15-6327-57-POWERS-ON-SEE-DETAILS
> Oscillograph:

More information about the cctalk mailing list