technical reference
37
SYNRAD OEM v30 Operator’s Manual Version 2
Technical overview
Figure 4-1
OEM v30 beam characteristics
Internal RF power supply
Firestar OEM v30 lasers are driven by a compact radio frequency (RF) oscillator mounted in the laser chas-
sis. The 30 VDC input voltage is converted into a high-power RF signal using an RF power oscillator. The
output from the RF oscillator (nominally at 83.5 MHz) drives the laser directly by exciting carbon dioxide
(CO
2
) gas in the tube to produce lasing.
Control circuit
Sensors built into the OEM v30 control board monitor the laser for conditions like under/over voltage,
over temperature, and other faults that pose a risk of damage to the laser. Additionally, laser operation is
controlled by a Laser Enable input.
Optical setup
After selecting a laser for a CO
2
laser processing system, the two most important elements to consider are:
(1) beam delivery optics to transmit the beam to the work area; and (2) focusing optics to focus the beam
onto the part or material to be processed. Each element is crucial in the development of a reliable laser-
based material processing system and each element should be approached with the same careful attention
to detail.
Beam delivery optics
Divergence, or expansion, of the laser beam is important in materials processing since a larger beam enter-
ing the focusing optic produces a smaller focused spot. Because the v30 laser beam diverges by 7 mm over
each meter of distance traveled, the laser should be mounted a distance of 1.0–1.5 m (40–60 in) away from
the work area and no closer than 0.75 m (30 in) for optimum performance. Right angle turning mirrors
(beam benders) are often used in conjunction with the laser mounting position to obtain this distance.
Expander/collimators are optical devices that increase beam diameter by a selectable magnification factor
while reducing beam divergence at the same time. Adding an expander/collimator substantially reduces
beam divergence and any variance in beam diameter caused by the changing optical path length in an XY
(“flying optics”) table application. In fixed-length delivery systems where the laser is positioned only one
meter away from the focusing optic and a small spot size is required, an expander/collimator is again the
best solution to provide the required beam expansion before reaching the focusing optic.
Note: Optical components in the beam path must always be aligned to the actual beam path, not the
laser faceplate. Because of slight variations in laser construction, the beam path may not always
be centered in, or perpendicular to, the aperture in the faceplate.
Beam Waist Diameter 2.5 mm ±0.5 mm at Output Aperture
Full Angle Divergence <7 mrad
Ø
