Galvo Scanning Heads: Efficient Precision

In the dynamic world of manufacturing – especially micromanufacturing – precision and efficiency are paramount. Generally speaking, however, “precision” rarely equates to “speed” or “efficiency.” Enter galvo laser scanners (or galvo scanning heads).

Laser Beam Delivery
The components that deliver a laser beam from the resonator to the parts are key elements that, ultimately, determine the performance of a system. These components include mirrors, shutters, fibers, and focus heads. The three most common types of focus heads are:

• Fixed – as the name implies, the optics in this head are fixed. The head is mounted to a fixed vertical programmable Z-stage and parts are moved to set points below it for welding. The laser is fired directly beneath the focus head, aiming the beam at one static point.
• Wobble/Weave –like the fixed head, the wobble/weave head is mounted to a fixed vertical programmable Z-stage and parts are moved to set points for welding. It differs from the fixed head however, in that the beam is moved with mirrors using a small oscillation to create a wobble or weave pattern. This wobble/weave creates a larger melt pool, enabling the joining of parts with lower manufacturing tolerances for part fit-up.
• Galvo Laser Scanners – like the other two, this head is also mounted to a fixed vertical programmable Z-stage, but rather than moving the parts to fixed positions for welding, the laser beam is steered – using mirrors – over the parts in the scanning area.

What are Galvo Scanning Heads?
A galvo laser scanner consists of two mirrors mounted on small rotary motors called galvanometers (“galvos” for short), which are then mounted orthogonally to each other so that the rotary motion of the mirrors translates to linear motion in the respective X- and Y-axes. Positioning in the X-Y field is related to a very small motion of the mirrors, so a 25 mm move takes just a few milliseconds. The mirrors’ light weight facilitates high-speed positioning, short settling times, and high-speed acceleration/ deceleration, all of which are ideal for high-speed, short-distance motion. This results in the ability to make many spot welds, or a seam weld, rapidly.

Advantages of Galvo Laser Welding in Manufacturing
The incorporation of a galvo scanning head in a laser welding system has many benefits:

• Increased Precision: with the ability to make fine, accurate adjustments, galvo laser scanners enable a level of precision that is essential in industries where even a micron’s deviation can lead to product failure.
• Enhanced Speed: speed is critical in manufacturing, and these scan heads can move the laser beam rapidly over a workpiece, significantly reducing welding cycle times.
• Versatility: galvo scan heads can easily adapt to different welding patterns and are suitable for a wide variety of materials and thicknesses.
• Reduced Heat Input: their fast processing speed results in minimal heat input, which is crucial in preventing material distortion and maintaining the integrity of the components.
• Automation: galvo scanning heads lend themselves to integration on the end of robotic arms (remote welding), into conveyor systems (welding on the fly), and other high-volume manufacturing situations where full automation is required.

Applications in Various Industries
Galvo scan head technology finds applications in several industries, including:

• Electronics: in the assembly of small components where precision is key
• Medical Devices: where the integrity and cleanliness of welds are vital
• Aerospace: for strong, precise welds in critical components

For more information about galvo laser scanners, their application, and how to transition from traditional laser welding to galvo scan laser welding, read the full article Galvo Scan Heads for Precision Laser Welding in Manufacturing on our website.