Field Lens Guide: Usage Scenarios & Installation
The Lumos Ultra uses interchangeable field lenses to optimize laser performance for different materials and applications. Each lens is color‑coded for its specific wavelength and use case.
Lens Types & Compatible Modules
| Lens Color | Compatible Module | Applications |
| Purple | UV (6W) | Surface engraving on glass, cutting, relief engraving (wood, stone, leather) |
| Green | UV (6W) | Glass surface engraving, cutting, 3D inner engraving inside crystal |
| Red | MOPA (60W / 100W) | Metal engraving, color marking on stainless steel, cutting (brass, stainless steel, aluminum), relief engraving (stone, wood, metal) |
Usage Scenarios
Purple UV Lens
- Best for: General UV work – glass surface engraving, cutting thin materials, and relief engraving on wood and stone.
- Not suitable for: Crystal inner engraving (use the green lens for that).
Green UV Lens
- Best for: Creating 3D engravings inside clear crystal or glass blocks without damaging the surface. Also works for standard surface engraving and cutting.
- Note: This lens is specifically optimized for transparent materials.
Red MOPA Lens
- Best for: Metal work – deep engraving, color engraving on stainless steel (iridescent and vivid colors), cutting brass, stainless steel, and aluminum, and relief engraving on stone, wood, and metal.
- Requires: The MOPA module to be installed on the Lumos Ultra.
Installation Steps
- Power off the machine and unplug it.
- Open the lid and locate the current field lens in the laser head assembly.
- Unscrew the existing lens. Place it in a clean, safe container.
- Remove protective caps from the new lens (both sides of the glass).
- Screw in the new lens until hand‑tight. Do not over‑tighten.
- Power on the machine and select the corresponding module (UV or MOPA) in the software.
⚠️ Important: Never fire the laser with the wrong lens installed for the active module. Using the purple UV lens with the MOPA module, or vice versa, can permanently damage the lens and the laser source.
Cleaning & Maintenance
- Clean the lens after each use when working with materials that produce smoke, dust, or residue.
- Use a lint‑free lens wipe or a soft microfiber cloth.
- Gently wipe in a circular motion – do not rub aggressively.
- Inspect for damage – If you see burn marks, scratches, or cloudiness that won’t wipe away, the lens may need replacement.
- Store lenses in their protective caps when not in use to prevent dust or scratches.
When to Replace a Field Lens
Replace the lens immediately if you notice:
- Visible burn marks that cannot be cleaned
- Deep scratches or chips on the glass