The focusing mechanism of the metallographic microscope is mainly composed of two parts: coarse focusing and fine focusing. The coarse focus adjustment mechanism is used for fast focus adjustment during microscopic operation. The micro-moving focusing mechanism is used for further cutting. In the process of application, you generally first adjust the focus coarsely, and then adjust the focus finely. In short, in order to achieve a satisfactory imaging effect, the two need to cooperate with each other.

1. Coarse focusing structure of metallographic microscope. The coarse focus adjustment mechanism generally adopts the meshing motion mode of the gear and the rack, and uses the Yanni 9 to perform the fine guide. According to the requirements of structure and quality, the parts of the ship-ni rail guide are made of alloy materials with stable structure and strong wear resistance, and are finely processed. When the rotation is rough, the surface of the full-phase sample will move relative to the optical system, and the adjusted system will move in a flat and straight line. Move the aging tail and the swallowtail pomegranate smoothly, and there is no loose or too tight phenomenon. The precision of the gear and the rack is ensured by adjusting the center distance between the rack and the gear.

2. Micro-focusing structure of metallographic microscope. The micro-movement mechanism has a lever type, a gear type, a planetary wheel type and other structural methods, among which the gear type coarse and fretting coaxial structure is used more commonly. The metallographic microscope has strict requirements on the micro-movement mechanism within the scope of the micro-motion call.