Graduation Year

2018

Location

Center for Natural Sciences, Illinois Wesleyan University

Start Date

18-4-2015 2:00 PM

End Date

18-4-2015 3:00 PM

Description

We have assembled a kit for an automated laser cutter system, intended to play an important role in a wide variety of student-led design projects on our campus. We began by electrically soldering the wiring for a powerful (60 Watt), pulsed infrared (10.6µm wavelength) CO2 laser beam, which can thermally induce shock waves that locally ablate a wide range of (non-reflective) materials. The laser tube itself generates significant heat when operating, so we also assembled the required water-cooling system. Given the high powers involved, careful alignment this invisible laser was required, to ensure that the beam is safely contained while traversing a sequence of mirrors, some of which are mounted to movable armatures controlled by computerized stepping motors, before redirection into an objective lens. Misalignment of the beam as it enters this final optical element results in significant aberration of the focal spot, diminishing the effectiveness and speed of the laser cutter, as well as the quality and resolution of the resulting cut. Again, as it is infrared laser, it cannot be seen by the naked eye, and so alignment is a challenge, which we addressed by using brief pulses to mark movable paper targets, which allowed us to trace out the trajectory of the beam.

Ideally, alignment should be sustained as the motorized armatures rapidly redirecting the beam to different regions of the material to be cut or optically etched. As an initial demonstration of the quality of our alignment, we successfully carved Aztec calendars onto wood and plastic plates. Because any matter ejected during ablation, or any smoke generated in the cutting process, has the potential to scatter the incident laser, we supply compressed air to clear the region above the target before each rapid pulse. Also we worked with the IWU Physical Plant to ensure adequate ventilation maintains a safe environment.

Included in

Physics Commons

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Apr 18th, 2:00 PM Apr 18th, 3:00 PM

Assembly, Alignment, and Maintenance of an Automated Laser Cutter

Center for Natural Sciences, Illinois Wesleyan University

We have assembled a kit for an automated laser cutter system, intended to play an important role in a wide variety of student-led design projects on our campus. We began by electrically soldering the wiring for a powerful (60 Watt), pulsed infrared (10.6µm wavelength) CO2 laser beam, which can thermally induce shock waves that locally ablate a wide range of (non-reflective) materials. The laser tube itself generates significant heat when operating, so we also assembled the required water-cooling system. Given the high powers involved, careful alignment this invisible laser was required, to ensure that the beam is safely contained while traversing a sequence of mirrors, some of which are mounted to movable armatures controlled by computerized stepping motors, before redirection into an objective lens. Misalignment of the beam as it enters this final optical element results in significant aberration of the focal spot, diminishing the effectiveness and speed of the laser cutter, as well as the quality and resolution of the resulting cut. Again, as it is infrared laser, it cannot be seen by the naked eye, and so alignment is a challenge, which we addressed by using brief pulses to mark movable paper targets, which allowed us to trace out the trajectory of the beam.

Ideally, alignment should be sustained as the motorized armatures rapidly redirecting the beam to different regions of the material to be cut or optically etched. As an initial demonstration of the quality of our alignment, we successfully carved Aztec calendars onto wood and plastic plates. Because any matter ejected during ablation, or any smoke generated in the cutting process, has the potential to scatter the incident laser, we supply compressed air to clear the region above the target before each rapid pulse. Also we worked with the IWU Physical Plant to ensure adequate ventilation maintains a safe environment.