This photo shows a graphics laser projector (as opposed
to a beam table or beam projector).
A white-light laser beam (hidden behind
the PCAOM) enters the polychromatic acousto-optic
modulator. The PCAOM can be thought of as a computer-controlled electric prism. It splits
the beam into two components: a beam with the desired colors and a "waste" beam.
The desired beam (red in this photo) exits the
PCAOM, bounces off a steering mirror, goes through a hole onto a 45-degree bounce mirror,
hits the X-axis scanner mirror, and bounces up onto the Y-axis scanner mirror which aims
it at the projection surface. The waste beam contains all the undesired colors (cyan in
this photo). The waste beam exits the PCAOM at a slightly different angle, so it can be
dumped onto a black surface.
The white-light laser in the photo is a Laser
Physics Argon/Krypton model WC-300. The compact projector head was designed and built custom for Pangolin. (This means the head is not commercially available.)
Not shown in the photo are the cables which
bring the RF signal (from the PCAOM driver) and the scanner signals (from the scanner
amp). Also, this projector differs from many others because it does not have a separate
shutter. Instead, the projector relies on the PCAOM to blank the beam when there is no
scanner signal. |