Laser marking LOGO instructions

June 10, 2022

Large format

The so-called large format, the control unit of the plotter was directly used on the laser equipment at the beginning, and the drawing pen was removed, and the position of the X-axis base point, the Y-axis base point and the original drawing pen at the (0, 0) point were respectively installed 45. ° Rewind mirror, install a small focusing mirror at the lower end of the original pen position to turn on the light path and focus the beam. Directly using the drawing software to output print commands can drive the operation of the optical path. The most significant advantage of this method is that the format is large, and basically can meet the marking requirements with low precision, and no special marking software is needed; The method has the disadvantages of slow marking speed, low control precision, large mechanical wear of the pen arm, poor reliability and large volume. Therefore, after the initial attempt, the large-format laser marking system of the drawing ceremony gradually withdrew from the marking market. The same type of large-format equipment applied now basically imitates the previous control process, driven by servo motor. The high-speed large-format system, along with the gradual improvement of the 3D dynamic focusing galvanometer scanning system, will gradually disappear from the laser marking field.

In the era of turning mirrors, because of the shortcomings of large-format systems, some high-speed galvanometer technologies have not been widely used in China. Some control engineers have developed a mirror-scanning system driven by stepper motors. The laser light that is derived from the resonant cavity is expanded, and is reflected by a gold mirror driven by two stepping motors mounted at 90°, and is output by the F-theta field lens to output to the processing object, and the gold mirror is rolled. The laser action points on the working plane are respectively moved on the X and Y axes, and the two mirrors cooperate to enable the laser to complete the movement of the straight line and various curves on the working plane. This kind of control process far exceeds the large format in terms of speed and positioning accuracy, so it can meet the requirements of the tool industry for laser control to a large extent, although it is compared with the internationally popular galvanometer scanning system. Significant gaps, but strictly speaking, the rise and gradual improvement of this design concept represents a milestone in China's laser applications, and is a typical symbol of China's ability to design and produce laser applications. Until the rise of megascopes in China, this control method gradually withdrew from the stage of Chinese laser applications.
Galvanic era
In 1998, large-scale application of galvanometer scanning systems in China began. [The so-called galvanometer, also known as ammeter, its design idea completely follows the design method of the ammeter, the lens replaces the hands, and the signal of the probe is replaced by a computer-controlled -5V-5V DC signal to complete the predetermined action. Like the mirror-scanning system, this typical control system uses a pair of folding mirrors. The difference is that the stepper motor that drives the lens is replaced by a servo motor. In this control system, the position sensor is used. The design idea of the negative feedback loop further ensures the accuracy of the system, and the scanning speed and repeat positioning accuracy of the whole system reach a new level. [1]
At present, the domestic laser marking can be divided into mask marking, array marking and scanning marking according to its working mode.
Mask type marking mask type marking is also called projection type marking. The mask marking system consists of a laser, a reticle and an imaging lens. The working principle is that the laser beam expanded by the celestial mirror is projected on the mask which is prepared in advance, and the light is transmitted from the engraving department. The pattern on the reticle is imaged onto the workpiece (focal surface) by a lens. Usually a mark is formed for each pulse. The surface of the material irradiated by the laser is rapidly heated to vaporize or chemically react, and a color change occurs to form a distinguishable clear mark. Mask type marking generally uses a CO2 laser and a YAG laser. The main advantage of mask marking is that a laser pulse can produce a complete mark including several symbols at a time, so the marking speed is fast. For high volume products, you can mark directly on the production line. The disadvantage is poor marking flexibility and low energy utilization.

Author:

Mr. Franky

Phone/WhatsApp:

+8618929582915