FILTER PRODUCTS
Galvo Scanners
Frequently Asked Questions
Galvo Scanners also known as “Galvanometer Scanners” or “Scanning Galvos” or simply “Galvos” are an essential component in the laser beam steering technology for many laser markers and laser engravers. A galvo scanner is comprised of a high performance motor that is able to rotate (oscillate) around an axis at a fast angular speed and a permanently attached mirror, which it rotates. Their high degree of linearity and reproducibility allow steering laser beams with high speed and precision.
The core of the galvo scanner is the galvanometer – an electromechanical actuator that deflects in response and proportional to the applied electric current. To precisely control the degree of rotation a servo-control system is used to calibrate and ensure the linearity and the reproducibility of the angular motion.
Galvo Laser Marker or Galvo Laser Engraver refers to laser machines that utilize gavo scanner based beam steering technology. They are equipped with a laser scan-head comprised of two galvo scanners and an F-Theta wide aperture lens that focuses the laser beam on to the object being engraved. Similarly, Flatbed Laser Markers or Flatbed Laser Engravers refer to the machines that utilize linear XY motion based beam steering technology. The Galvo Lasers are characterized by a high processing speed compared with flatbed laser systems. On the downside, galvo lasers typically have much smaller work field compared with that of flatbed lasers. The work field (area) for galvo lasers is primarily determined by the aperture and the focal length of the F-Theta lens on the galvo scan head.
Linearity (and conversely nonlinearity) is a measure of deviation of travel path from that identified by the built in feedback system.
The rotor inertia of a galvo scanner measures the amount of torque needed to cause a unit of angular acceleration about the axis of rotation.
The repeatability of a galvo scanner measures the degree of precision of the scanner to orient the mirror to the same position. For example, 5 urad of repeatability means that if the same command to position the galvo at a specified angle is given, the deviation from the set position upon subsequent measurements will be less than or equal to 5 urad.
If you are looking for a galvo scanner as a replacement, you will want to ensure the compatibility of the replacement part with your laser scan head. The key parameters to look out for are the max beam (aperture size), the wavelength coating of the mirror, scan range, torque, dimensions, and weight. You will also want to look into the input electrical requirements and interface protocols to ensure that it’s compatible with your system.
Did You know?
1 - Intro to Laser Scanning
2 - Laser Marking System: Complex Design For Elegant Patterning