In the field of laser marking, fiber laser marking machines equipped with electric lifting systems have become the mainstream, and the **auto-focus function** stands as their core upgrade feature, which has thoroughly optimized the operation and efficiency of traditional marking machines. I. What is the Auto-Focus Function? The core of laser marking lies in focusing the laser beam accurately on the workpiece surface to create clear marks, and this process is called "focusing".   Traditional marking machines rely on **manual focusing**: operators need to manually adjust the height of the laser head according to the thickness of the workpiece and repeatedly calibrate it with tools, which is time-consuming and easily affected by human factors.   The auto-focus function**, built on the basis of the electric lifting system, realizes a closed-loop process of "automatic detection - automatic calculation - automatic adjustment" through high-precision sensors (such as laser displacement sensors and CCD vision sensors), an intelligent control system, and a servo motor. The specific workflow is as follows: 1. The sensor detects the distance between the workpiece surface and the laser head in real time. 2. The system compares the "actual distance" with the "optimal focus distance" and calculates the height compensation value required for lifting. 3. The servo motor drives the electric lifting mechanism to align the laser focus with the workpiece surface in an instant (0.1-0.5 seconds), with no manual intervention throughout the process. II. Core Advantages of Auto-Focus Compared with manual focusing, auto-focus achieves upgrades in multiple aspects such as efficiency, precision, and operation: Efficiency Improvement & Cost Reduction**: It eliminates the need for manual calibration. When switching between workpieces of different thicknesses, "marking starts immediately after loading", avoiding downtime waste and significantly improving continuous production efficiency. Stable Precision**: Relying on high-precision sensors (with an error of ±0.001mm) and a servo drive, the focusing error is less than 0.005mm, ensuring consistent marking effects across different batches of workpieces and reducing defective products. Lowered Operation Threshold**: Operators do not need to master complex focusing skills. The training period is shortened from 1-2 weeks to 1-2 days, reducing reliance on labor and operational errors. -Strong Adaptability**: It can automatically adapt to workpieces of different thicknesses (0-100mm, customizable) and even curved workpieces, without the need for frequent parameter adjustments, thus enhancing the versatility of the equipment. Good Protection Performance**: It identifies abnormal workpiece positions in advance and triggers shutdown protection to avoid collisions between the laser head and the workpiece; meanwhile, it ensures the stable application of laser energy, prolonging the service life of the equipment and reducing workpiece waste. III. Conclusion Auto-focus and electric lifting complement each other, enabling fiber laser marking machines to evolve from "semi-automatic" to "intelligent, fully automatic". For enterprises, it can adapt to scenarios such as mass production and multi-specification processing with lower labor costs, higher efficiency, and more stable quality, serving as a key driver for cost reduction and efficiency improvement.