1.pay attention to the marking range
The focusing lens of the marking machine has a range, and the pattern marking beyond the range will be unclear or the pattern will not be displayed, and the position beyond the unevenness will appear.
2.thermal lens phenomenon
When the laser passes through the optical lens (refraction, reflection), it will cause the lens to generate heat and produce a slight deformation. This deformation causes the laser focus to rise and the focal length to become shorter. If the machine is fixed and the distance is adjusted to the focus after the laser is turned on for a while, the laser energy density acting on the material changes due to the thermal lens phenomenon, resulting in uneven marking effect.
3.Problems with raw materials
Materials are sensitive to laser energy reactions. Generally, under the same material, the laser energy reaches a material damage threshold is certain. When the thickness of the material coating is different, or some other physicochemical treatment process is not uniform enough, it will also cause unevenness of the effect after laser marking.
4.the marking machine equipment is not placed balanced
Since the two are not horizontal, the length of the laser beam passing through the field lens and reaching the workpiece is inconsistent. The energy of the laser falling on the workpiece will have an inconsistent energy density, and the effect will be exhibited on the material. Not uniform.
5.the optical path output position is blocked or stained
The laser output head, fixed fixture, and galvanometer are not adjusted, which causes some spots to be blocked when the laser passes through the vibrating lens. The spot on the multiplier is non-circular after being focused by the field lens, which may result in no effect. Evenly. There is also a case where the galvanometer deflecting lens is damaged and cannot be reflected well when the laser beam passes through the damaged area of the lens. Therefore, the laser beam is inconsistent with the laser energy in the damaged area of the lens and the non-damaged area of the lens, and the laser energy ultimately acting on the material is also different, thereby making the marking effect uneven.