Oct 8, 2026
How Does Laser Spot Size Affect Handheld Laser Welding?
Laser spot size affects energy density, penetration, weld width, and heat input. Choosing the right spot size helps achieve more stable and consistent handheld laser welding results.
Laser spot size directly affects how energy is distributed on the workpiece. Choosing the right spot size can help control penetration, weld width, and heat input.
1. Smaller Spot Size
A smaller spot concentrates laser energy in a smaller area.
- Higher energy density
- Deeper and more concentrated penetration
- Suitable for thinner or precision welding
- Can increase the risk of overheating if the power is too high
2. Larger Spot Size
A larger spot spreads the laser energy over a wider area.
- Wider heat distribution
- Wider weld area
- Lower energy density
- Can be useful when a wider and more uniform weld is required
3. Match Spot Size With Power
Spot size should not be considered separately from laser power and welding speed.
For example, increasing the spot size while keeping the same power reduces energy density. If penetration becomes insufficient, the welding parameters may need to be adjusted accordingly.
When changing spot size, test one parameter at a time and check weld width, penetration, and heat-affected area. This makes it easier to find a stable combination for different materials and thicknesses.
