- Multi Position Marker (MPM)
Laser
Galvo technology to continuously
laser mark
material, move the finished piece out and at the same time move the next
piece into the marking area. We have achieved speeds thought to be
impossible a few years ago.
Galvo Laser Cutting and Marking (GLC)
Laser
Galvo technology to cut/mark
material, move the finished piece out and move the next piece into the
processing area. What took over 4 minutes to be cut on
a competitors machine, GLC did it in 78 seconds.
The galvanometer
(often abbreviated to "galvo") is a current-sensitive device that operates in
a similar manner to an analogue meter. In an
analogue meter, a small coil of wire is wound around a lightweight aluminum
bobbin that is suspended in the gap of a permanent magnetic field by means
of pivots. The coil has a thin needle attached which extends over an
indicating face that is the part of the meter you see.
When electrical energy is applied to the coil, it develops a magnetic
field that will act against the field in the gap causing the coil to move
the indicating needle proportionally to the current applied. Some meters are
designed to be at rest at one end of the scale (such as analogue VU meters),
while others are at rest in the centre of the scale (an analogue FM tuning
indicator for example).
The first type of meter is a unipolar device as it reacts only to an
increase in the current applied; while the second type of meter is a bipolar
device as it reacts not only to the current applied, but also the polarity
of the current. When the signal is negative, the indicating needle moves in
one direction away from its central position: when the signal is positive,
it moves in the opposite direction away from its central position.
Unfortunately meter movements are too small, to slow, and to delicate to
allow us to attach a mirror and control laser beam deflection. We must use a
more rugged type of device, a scanning type galvanometer. Galvos can be thought of as very high
speed, current sensitive, limited rotation electrical motors. The amount of
rotation (within the rotational limits of the galvo) is determined by the
amount of current applied; with the direction of the limited rotation
controlled by the polarity of the current applied. Galvos (scanners) are a
current-sensitive bipolar device that are at rest in the centre of their
limited rotation.
Usage Note:
The words galvo or galvanometer refers to the
basic galvanometer itself, without an attached mirror. Scanner refers to a
galvanometer that has a mirror attached to it such that it can deflect a laser
beam by applying appropriate control signals.
