This auto focus is similar to the proximity switch sensor.
It works with up and down moving table.
The utility model relates to an automatic focusing structure for a laser carving machine. An electronic probe is mainly vertically arranged on a pen saddle of the laser carving machine; the electronic probe is designed into a circular pipe with an appropriate length; the top part of the circular pipe has a flange; the upper and the lower sections of the circular pipe are respectively provided with a concave ring for the clamping and the positioning of a positioning column on the pen saddle; the circular center part of the end face of the circular pipe is provided with an open hole for that internal a two-section type electronic sensing bar projects to the outer part. By that a platform driven by a Z shaft electrically rises, the surface of a processed object is in contact with the probe. According to lens focus distances stored by software, automatic focusing can be completed by that the platform drops down to a focusing face after calculation. When the utility model operates, the electron probe can be upwards folded without touching operation objects.