Yueming MF20 Product Manual page 39

release a lot of gas and splashes, which will damage the lens. When the contaminant falls on the
lens surface, it will absorb energy from the laser beam, resulting in thermal lens effect. If the lens
hasn't formed thermal stress, the operator can disassemble and clean it. The method should
avoid damage to the lens and further contamination.

General Operation Principles
In the installation and cleaning process of lens, any sticky material, even nail print or oil
droplets, will increase the absorption rate of the lens and reduce service life.
Therefore, the following precautions are required:

Do not use suction device or inflatable equipment to avoid scratching the lens
surface;

Hold the edge of the lens rather than the film when take lens;

The lens should be stored in a dry and clean place for testing and cleaning. A good
console should have several layers of cleaning tissue or lens tissue on the surface;

The operator should avoid talking over the lens, and keep food, beverages and
other potential contaminants away from the working environment.

The correct cleaning method
In the process of cleaning the lens, the only purpose is to remove the contaminants, and
avoid further contamination and damage. To achieve this goal, people tend to use an approach
with relatively small risk. The following procedure is established for this purpose.
First, first blow the floating material off the lens surface with air ball, particularly the fine
particles and wadding material on the lens surface. But do not use compressed air on the
production line, because the air will contain oil and water droplets, which will deepen the lens
contamination.
Secondly, clean the lens with acetone or anhydrous alcohol (reduce the possibility of lens
contamination)
Dip the lens paper in acetone and clean the lens in the light, and move circularly. Once the
lens paper is dirty, it must be replaced. The cleaning must be finished in one time to avoid
scratching.
Some contaminants and lens damage can't be removed by washing, for example, film burn
due to dirt, stripping caused by condensation. In order to restore perfect performance, the only
way is to replace the lens.
31