Novanta SYNRAD Pulstar p100, User Manual

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LASER AND TUBE DESIGN PAGE | 29
The p100/150’s patented “p” technology, include RF components that are integrated within the laser
body itself, completely eliminating the need for external RF boxes and cables. The net result is a
symmetrical laser beam from a small but powerful laser capable of operating for many years with
virtually no maintenance. Based on the same proven technology behind the success of NOVANTA t-
Series, the p100/150’s peak pulse power takes materials processing a step further by allowing users to
cut faster and drill deeper through a variety of materials with minimal heat affect zone and superior cut
edge quality. The p150’s longer tube design provides excel-lent power stability, making it ideal for
applications that demand the highest levels of consistency and precision. ’s unique extruded aluminum
envelope offers excellent heat transfer, long gas life, and low operating costs in contrast to other laser
tube technologies. In addition to being the vessel that maintains the lasing environment, the aluminum
tube is also the structural platform that integrates the laser’s optical, electrical, and cooling components.
Heat Removal
Heat generated by the plasma is transferred to the bore walls by diffusion. Collected heat is transferred
to the water in the cooling tubes by conduction of the electrodes and aluminum envelope. The coolant
path is directed through corrosion-resistant copper alloy tubing to regulate laser temperature for
maximum stability.
Optical resonator
The optical resonator, in conjunction with the electrodes and the gas mixture, generates the laser beam.
p100/150 resonators are comprised of three optical elements: a front mirror, a rear mirror, and an output
coupler (window). These optical elements are fastened to the tube’s exterior and are exposed to its
interior through holes in the end caps. O-rings are sandwiched between optical elements and the end
cap to form a gas seal and to provide a flexible cushion that allows the slight movement necessary for
alignment. All optical elements are aligned and locked into place by factory technicians before the laser
is shipped.
The output beam is quite circular as it exits the resonator, transitions to a Gaussian-like mode quality (M2
factor) of < 1.2. Beam waist diameter is typically 7.5 mm (p100) – 8 mm (p150) at the output aperture
and full-angle divergence due to diffraction is approximately 1.9 milli-radians (a 1.9 mrad divergence
means that beam diameter increases 1.9 mm over every one-meter distance traveled).
RF and control circuitry
The p100/150 is driven by two compact radio frequency (RF) power supplies mounted internally in the
laser chassis. The 48 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 (CO2) gas in the tube to produce lasing.
Control circuitry built into the laser interrupts operation if any critical parameter is violated. Switches and
sensors on the control board monitor various conditions and parameters that, if exceeded, pose a risk of
potential damage to the laser. Additionally, laser operation is interrupted in response to the following
conditions: (1) the Shutter Open Request input signal is missing; (2) an over temperature condition
occurs; (3) the Remote Reset/Start Request input signal is enabled; (4) the Remote Interlock input signal
is missing; or (5) any fault is present.
Beam conditioning
The p100/150 laser incorporates a sophisticated beam conditioning system that cleans up the beam to
remove the side lobes and improve beam quality. This is accomplished by turning the laser beam back