In laser systems, optical lenses are consumable items. To extend their service life and reduce operating costs as much as possible, it is essential to clean the lenses strictly following this standard.
During the replacement process, care must be taken when placing, inspecting, and installing optical lenses to avoid damage and contamination. Once a new lens is installed, it should be cleaned regularly to maintain its performance.
Laser Cutting Machine Lens Cleaning Standard Operating Procedure
When the laser cuts materials, the working surface releases a large amount of gas and splatter, which can damage the lens. Contaminants on the lens surface can absorb energy from the laser beam, leading to the thermal lens effect.
If the lens has not yet developed thermal stress, the operator can disassemble and clean it. During the installation and cleaning process of the lens, even a tiny bit of adhesive or a fingerprint can increase the lens’s absorption rate and decrease its service life.
For daily laser lens operation, the following preventive measures must be taken:
- Never install the lens with bare fingers. Wear finger cots or rubber gloves.
- Avoid using sharp instruments to prevent scratching the lens surface.
- When handling the lens, do not touch the coating. Hold it by the edge.
- Inspect and clean the lens in a dry, clean area. A good workbench should have several layers of cleaning tissue and several cleaning lens paper sheets.
- Users should avoid talking above the lens and keep food, beverages, and other potential contaminants away from the work environment.
During the lens cleaning process, methods with relatively low risk should be adopted. The following steps are established for this purpose, and users should follow them:
- Use a blower bulb to blow away debris from the surface of the lens, especially when there are tiny particles and lint on the surface. This step is essential. However, do not use compressed air from the production line, as it may contain oil mist and water droplets, which can further contaminate the lens.
- Use analytically pure acetone for a gentle lens cleaning. This grade of acetone is virtually anhydrous, reducing the likelihood of lens contamination. Dip a cotton ball in acetone and clean the lens under illumination, making circular motions. Replace the cotton swab as soon as it gets dirty. Complete the cleaning in one go to avoid streaking. If the lens has two coated surfaces, such as a double-sided lens, clean each side using this method. Place the first side on a clean lens paper for protection.
- If acetone cannot remove all contaminants, use diluted vinegar for cleaning next. Vinegar cleaning works by dissolving contaminants without damaging the optical lens. This vinegar can be lab-grade (diluted to 50% strength) or household white vinegar containing 6% acetic acid. The cleaning procedure is the same as with acetone, followed by acetone to remove the vinegar and dry the lens. Frequently change the cotton ball to completely absorb the acid and hydrates until the lens is clean.
- When contamination and lens damage cannot be removed through cleaning, particularly due to metal splatter and dirt causing coating burnout, the only way to restore good performance is to replace the lens.
