Focusing Lens And System For Laser Cutting Machine Cutting Head

Focusing lens
In order to use the energy of the laser beam for cutting, the original beam emitted by the laser must be focused by the lens to form a high-energy density spot. According to Gaussian optical theory, the power density is highest at the focus. The longer the focal length of the lens, the larger the focal spot, the lower the power density, but the focal depth is large (the focal depth refers to the distance between the two spots with a diameter change of 5% on both sides of the focus, also known as the effective cutting range in cutting), and the operating tolerance is large. The effective range of a 5-inch lens is greater than that of a 3-inch lens. This is why medium-long focal lenses are suitable for thick plate cutting, and have lower requirements for the spacing stability of the tracking system, but require high laser output power. On the contrary, short-focus lenses are only suitable for thin plate cutting below D3. Short focus has stricter requirements for the spacing stability of the tracking system, but it can greatly reduce the output power requirements of the laser.
Tracking system
The focusing and tracking system of a laser cutting machine is generally composed of a focusing cutting head and a tracking sensor system. The cutting head includes light guide focusing, water cooling, air blowing, and mechanical adjustment parts; the sensor is composed of a sensor element and an amplification control part. The tracking system is completely different depending on the sensor element. There are two main types of tracking systems: one is a capacitive sensor tracking system, also known as a non-contact tracking system, and the other is an inductive sensor tracking system, also known as a contact tracking system.