In the lens installation and cleaning process, any bit of sticky material, even nail marks or oil droplets, will increase the lens absorption rate, reduce the service life. Therefore, the following precautions must be taken:
1. Never install lenses with bare fingers. Gloves or rubber gloves should be worn.
2. Do not use sharp instruments to avoid scratching the lens surface.
3. Do not touch the film when removing the lens, but hold the edge of the lens.
4. Lenses should be placed in a dry, clean place for testing and cleaning. A good table surface should have several layers of cleaning paper towels or paper swab, and several sheets of cleaning lens sponge paper.
5. Users should avoid talking over the lens and keep food, drink and other potential contaminants away from the working environment.
Correct cleaning method
The sole purpose of the lens cleaning process is to remove contaminants from the lens and not cause further contamination and damage to the lens. In order to achieve this goal, one should often use relatively less risky methods. The following steps are designed for this purpose and should be used by users.
First, it is necessary to use air ball to blow off the floss on the surface of the component, especially the lens with small particles and floss on the surface. But do not use compressed air from the production line, because these air will contain oil and water droplets, which will deepen the pollution of the lens
The second step is to apply acetone to clean the lens slightly. Acetone at this level is almost anhydrous, which reduces the possibility of lens contamination. Cotton balls dipped in acetone must be cleaned under light and moved in circles. Once a cotton swab is dirty, change it. Cleaning should be done at one time to avoid the generation of wave bars.
If the lens has two coated surfaces, such as a lens, each surface needs to be cleaned in this way. The first side needs to be placed on a clean sheet of lens paper for protection.
If acetone does not remove all the dirt, then rinse with vinegar. Vinegar cleaning uses the solution of dirt to remove dirt, but does not harm the optical lens. This vinegar can be experimental grade (diluted to 50% strength) or household white vinegar with 6% acetic acid. The cleaning procedure is the same as acetone cleaning, then acetone is used to remove the vinegar and dry the lens, changing cotton balls frequently to completely absorb the acid and hydrate.
If the surface of the lens is not completely cleaned, then use polishing cleaning. Polishing cleaning is to use a fine grade (0.1um) aluminum polishing paste.
The white liquid is used with a cotton ball. Because this polishing cleaning is mechanical grinding, the lens surface should be cleaned in a slow, non-pressure interlaced loop, not more than 30 seconds. Rinse the surface with distilled water or a cotton ball dipped in water.
After the polish is removed, the lens surface is cleaned with isopropyl alcohol. Isopropyl ethanol holds the remaining polish in a suspension with water, then removes it with a cotton ball dipped in acetone. If there is any residue on the surface, wash it again with alcohol and acetone until it is clean.
Of course, some pollutants and lens damage can not be removed by cleaning, especially the film layer burning caused by metal splashing and dirt, to restore good performance, the only way is to replace the lens.
Correct installation method
During the installation process, if the method is not correct, the lens will be contaminated. Therefore, the operating procedures mentioned earlier should be followed. If a large number of lenses need to be installed and removed, it is necessary to design a fixture to accomplish the task. Special clamps can reduce the number of contact with the lens, thereby reducing the risk of lens contamination or damage.
In addition, if the lens is not installed correctly, the laser system will not work properly, or even be damaged. All co2 laser lenses should be mounted in a certain direction. So the user should confirm the correct orientation of the lens. For example, the high reflective surface of the output mirror should be inside the cavity, and the high permeable surface should be outside the cavity. If this is reversed, the laser will produce no laser or a low energy laser. The convex side of the final focusing lens faces into the cavity, and the second side through the lens is either concave or flat, which handles the work. If it is reversed, the focus will become larger and the working distance will change. In cutting applications, resulting in larger slits and slower cutting speed. Reflectors are the third common type of lens, and their installation is also critical. Of course, with a reflector it is easy to identify the reflector. Obviously, the coating side is facing the laser.
Generally, manufacturers will mark the edges to help identify the surface. Usually the mark is an arrow, and the arrow points towards one side. Every lens manufacturer has a system for labeling lenses. In general, for mirrors and output mirrors, the arrow points to the opposite side of the height. For a lens, the arrow points toward a concave or flat surface. Sometimes, the lens label will remind you of the meaning of the label.
Post time: Dec-24-2021
