Laser / Workshop reference
Laser lenses, focus & nozzle clearance
Identify the optics and focal reference before testing line quality or cut settings.
In everyday language
Know where the beam does its work
Focus is the position where the beam is concentrated for the intended process. Its narrow region is sometimes called the waist.
Compare the focus instructions for your exact installed laser and lens with the actual material surface.
What to notice: Keep the focus method and material thickness in the test notes. Do not assume two laser systems use the same distance.
Does changing material thickness leave every focus setup unchanged?
No. Follow the system's instructions and establish the reference for the new material.
No need to know the vocabulary first
A few words, explained
- LightBurn
- A program for preparing cutting and engraving jobs for supported laser machines.
- Stock
- The wood or other material you start with.
How it works
Focusing places the beam waist near the chosen reference. Lens and machine geometry determine the working distance; a software focus offset is not a universal nozzle gap.
When to consider it
Use the installed optic's specified focal setup and a test method supported by the machine and controller.
Where it does not apply
Do not substitute a different wavelength's lens, use an unknown cleaning solvent or assume a CO₂ procedure applies to a diode or galvo.
Before the first cut
- Follow the manufacturer's optics inspection and cleaning procedure with the machine in its required safe state.
- Use its focus gauge or documented focusing method; record the reference plane and sign convention for offsets.
- LightBurn's automated Focus Test requires a compatible motorized Z axis. Check all Z travel and nozzle clearance before using it.
If the result looks wrong
Stop the machine and make it safe to inspect before checking the tool or workpiece.
Wide or inconsistent line
Check focus, material flatness and optic cleanliness before altering power.
Nozzle collision risk
Stop and verify working distance and the highest stock or fixture point; do not run a Z sweep without clearance.
Use the matching calculator
Calculator outputs describe geometry, time or cost—not permission to operate at those values.
Make the setup repeatable
In Machine & Bit Settings, keep these details in the standard fields, additional fields and setup notes. Record a test date only after testing that exact setup.
- Laser type, optic ID and focal reference
- Focus offset and sign convention
- Nozzle and air-assist setup
No cutting settings are automatically supplied or saved by this guide.
References & exact specifications
These public references explain the tool families or software features. Locate your exact part number and machine manual before setup; product families are not interchangeable.
Guidance reviewed September 2026. Diagrams are original simplified explanations, not manufacturer drawings.