"Why is the actual effect of laser engraving uneven?"
1. Mark the content of the corresponding area with off-focus marking: The method of off-focus marking must take into account the problem of laser energy. This is because each focusing mirror has a matching focal depth area, and the off-focus method is used. It is easy to cause the large area marking pattern, the edge is at the critical point of the depth of focus or beyond the depth of focus area, which is easy to cause the actual effect of non-uniformity.
2. Thermal lens phenomenon: When the light passes through the optical lens (refraction, reflection), the lens will be hot and cause small deformation. This deformation will raise the focus of the collected light and shorten the focal length. If the machine is fixed and the distance is adjusted to the focal point, after a certain amount of time the light is turned on, the energy density of the light acting on the raw material will change due to the thermal lens phenomenon.
3. The output light spot of the paid-in light is covered, that is, the light spot of the paid-in light beam is missing after passing through the galvanometer and field lens, and it cannot be rounded: The light-paying output head, the fixed fixture and the galvanometer are not aligned, which causes the light to pass through the vibration. A part of the light spot is covered by the lens, and the light spot on the frequency doubling film is non-circular after being collected by the field lens. There is another situation, that is, the galvanometer deflection lens is damaged, and when the light beam passes through the damaged area of the lens, it cannot be effectively reflected. Therefore, the laser energy of the laser beam passing through the damaged area of the lens is different from that of the non-damaged area of the lens, and the result is that the light energy acting on the raw material is not the same.
4. Due to the raw material, such as the thickness of the film on the surface of the raw material is not the same or the physical properties are changed: The raw material is particularly sensitive to the response of the light energy. Generally, under the same raw material, it is corresponding when the light energy reaches the damage threshold of the raw material. When the thickness of the coating on the surface of the raw material is different, or some other physical processes are not uniform.
5. The laser engraving machine equipment is not aligned on the same horizontal plane, that is, the photoconductor lens or the field lens lens and the production and processing table are not on the same level: Since the two are not on the same level, the paid light beam will reach the production and processing items after passing through the field mirror. The length of the distance is inconsistent, and the result is that the energy that falls on the produced and processed items will have different energy densities.