1. Power size
The size of the laser power has a great impact on the life of the protective lens. For low-power laser equipment, such as a 1500-watt laser cutting machine, the service life of the protective lens may be as long as two or three months, which is normal. For high-power equipment, the protective lens is more likely to burn out. For example, when debugging the process, it is normal to consume four or five lenses a day. Therefore, the greater the power, the faster the protective lens will be worn out.
2. Unclean air source
Unclean air source is one of the main reasons for damage to the protective lens. The air sources here include oxygen, air and nitrogen. Unclean air is the most common, especially the air produced by the air compressor. If it does not meet the standards and contains oil, water and dust, it will frequently burn the protective lens.
In this case, a circle of flower-like stains often forms on the surface of the lens, especially around the lens, which is 100% caused by unclean air. The dust particles in the air can be detected by irradiating the light of the mobile phone. At this time, the air compressor needs to be maintained or replaced with a higher quality filter.
White spots gather in the light-transmitting area in the middle of the lens, which may be caused by the escape of aluminum oxide in the desiccant and adhesion to the protective lens. This situation is mostly caused by unclean oxygen or nitrogen. Especially when using liquid canned gas for many years, the gas supplier should be asked to clean the tank to avoid contaminating the protective lens.
3. The perforation process is not suitable
If the perforation process is improper, such as incorrect perforation parameter settings, oil residue will splash onto the protective lens during drilling, forming black contamination spots. This situation usually occurs on the lower surface of the protective lens.
4. Improper operation when replacing the protective lens
When replacing the protective lens, if the operation is not standardized, dust may fall on the protective lens, resulting in burn spots on the upper surface. Therefore, correct replacement operation and a clean environment are essential to extend the life of the protective lens.
5. Damage to other lenses or fiber end faces of the cutting head
If other lenses of the cutting head are damaged, or there are burn spots on the fiber crystal end faces, the upper surface of the protective lens will be frequently burned. First, check whether the middle protective mirror is contaminated. It is likely that the dust falls on the protective mirror due to the contamination of the middle protective mirror. Then check the focusing mirror and the collimating mirror. Finally, consider whether there are burn points on the fiber end face.
6. Quality problems of protective lenses
If the quality of the protective lens is too poor, its service life will also be shortened. Some lenses that look clean will be found to have a lot of dust upon careful inspection. This is mainly due to the large differences in coating processes and lens quality of different manufacturers. Therefore, it is recommended to choose higher quality protective lenses to reduce the trouble of frequent replacement.