Laser Shutter Scanner Digital to Analoge Convertor (DAC

LASER
The Laser is the device that creates the light patterns you
see before you. While Lasers have many diverse
applications, the typical use for the otne you see here is
entertainment lighting such as concerts.
Wiring key
Power Supply
120 VAC
24 VCD
24 VDC
12 VAC
Galvo umbilical
120 AC
Main Power supply
24 VDC
The power supply takes the eletrical
power from the wall and transforms it
into a smaller power that the laser can
use. Here, both plu and minus 24
volts are created. This is used to
swing the galvos both left and right.
Position signal
Galvo Driver
There are several smaller power
supplies which feed off of the main
supply. These are to further modify
the power to suit that specific
sub-system.
Galvo Driver
Galvo Driver
Scanner
DAC Power
Supply
Galvonometer & Driver
A Galvonometer is a small motor
that, instead of spinning, wiggles
back and forth extreemely fast.
Laser controller
Rotating Flag
The Galvonometer Driver is a circuit
that wiggles the galvo and keeps
track of it’s position very accuratly.
The wiggling it done through
magnets. As the circuit switches the
magnetic field in a coil back and
forth, the rotating part called the
armature follows it, moving back
and forth.
DAC
Shutter
Photo-Detector
Laser
LED
To keep track of the position, the
galvo driver uses a small flag on the
end of the armature. As this flag
wiggles, it blocks and unblocks light
from an LED. This light is then
detected by two small photocells.
Inches
Digital to Analoge Convertor (DAC)
Scanner
Shutter
Y
The scanner is what moves the laser
beam around to draw the picture.
Analog
Digital
X
The Digital to Analog Convertor,
also known as a DAC, takes the
digital signals from the
computer and turns them into
analog signals for the galvo
drivers. It also has controls to
adjust the gain (size) and offset
(position) of the signal. It’s
connected to the computer
through the parallel port.
Gain
Offset
It works by bouncing the laser beam
off of two small mirrors. These
mirrors are connected to two galvos
that rotate them.
The computer controls the gavlos to
move the mirrors and trace out the
shape you want with the laser.
There is only one laser beam, but
the galvos wiggle the mirrors so fast
it looks like there are many.
Laser
The Shutter is what blinks the laser on and
off. Without it, all the shapes the laser
would draw would be connected with a
line. This allows the laser to essentially
draw ‘blank’ lines.
It works by having a galvo rotate a small
notch in front of the laser so it blocks the
beam. It does this realy realy fast.
Without
With
IR Diode
Frequency
doubler
Mirror
Lenses
Lasing Medium
The laser is what produces the narrow
beam of light. Lasers are special kinds
of light because they contain only one
color. This is what we call a coherent
lightsource. If you were to put a blue
filter in front of a green laser, you would
not get any blue light coming out. To get
colors, many lasers are combined.
Photodiode
Mirror
Tuning filter
Beam Splitter
This laser is a DPSS laser. That stands
for Diode Pumped Solid State. These
lasers work by shoting a high power
infrared laser into a special crystal that
turns it green, but lowers it’s intensity.
The laser also requires a controler to
monitor all of it’s sensors and keep the
internal componates at a specific temp.