Laser Marking Principle Demystification And Technical Analysis

Laser marking equipment can be used for non-destructive marking of various materials, under the action of high-energy laser beams, so that the processed workpieces undergo changes in color and nature, leaving a permanent mark. Its fast speed, high efficiency, non-polluting characteristics make it more widely used.
According to different working principles and technical characteristics, laser marking can be mainly divided into three categories of dot-matrix laser marking, mask laser marking and vibrating mirror laser marking, with their own characteristics and scope of application.
Dot-matrix laser marking
Multiple small lasers can emit multiple beams of laser light, through the reflector and focusing lens, and then form a number of burning points on the object, these points on the surface of the workpiece to form a series of densely arranged dot-matrix marking.
With such dot matrix marking, the shape of the marking are made up of multiple small round dimple points and can be composed of information such as patterns, text or 2D codes. For numbers, seven dots are enough for strokes in the vertical direction, while five dots can be used for strokes in the horizontal direction, forming a 7*5 dot matrix arrangement similar to a dot matrix screen is enough to see clearly.
Dot-matrix laser marking is slower and the depth of the cauterized point is deeper, so it is suitable for processing shapes with little concavity or convexity of the workpiece. At the same time, since the dot-matrix method consists of multiple burning points, if you magnify it to a certain magnification and observe it, you may be able to see that there are some unclear and unsmooth places between the burning points.
Mask laser marking
The principle of mask technology is not complicated, is through the laser beam path set mask, and then the mask on the pattern or text information projected onto the surface of the workpiece processing method. However, the mask process itself has a high technical threshold, requiring superior technology and precision equipment, and is used in high-precision industries such as photolithography.
In laser marking, the mask plate is usually made of high-temperature-resistant metal material, using mechanical or chemical hollowing technology to make the required patterns or characters on the mask plate, using parallel laser beams to pass through the gaps of the mask plate patterns or characters, and then after convergence of equal proportions to hit the workpiece with the proportionally scaled-down drawings on the mask plate.
Mask marking is a very characteristic laser marking method, which is somewhat like an improved version of the ancient "movable type printing". If multiple copies of the same pattern need to be reproduced, the laser head can remain stationary when using mask marking, effectively increasing efficiency. However, the production of the mask plate itself is more complicated, and is not suitable for the processing of patterns that need to change frequently.
Vibrating mirror laser marking
Vibrating mirror laser marking is currently the more mainstream laser marking method.
To mark the desired shape on a two-dimensional plane, two dimensions, the X-axis and the Y-axis, need to be determined. Introduce a laser beam into the two perpendicular to each other vibrator, respectively, to guide the laser in the XY axis scanning apart, with the software to control the position of the vibrator can guide the laser in the two-dimensional plane to hit the desired graphics.
If mask laser marking is like printing with movable type, then galvanometer marking is like the process of writing with pen and paper. The use of computers to handle the entire marking process, drawing graphics with high efficiency, more accurate graphics, more flexible control, can realize the marking of complex graphics. And the optical path is in sealed state, which is suitable for different working occasions.