Wide band laser heat treatment using pyramid polygon mirror

A wide laser beam optical system for laser heat treatment processing has been designed with a pyramid polygon mirror, which is able to adjust the amplitude and frequency. It consists of a rotating pyramid polygon mirror made of copper and a cooling part that protects the surface of the mirror from damage by heat. The system provides a linear laser heat source with the wide scanning width. This can increase the efficiency of production and quality of products. The CO₂ laser heat treatment has been processed on SNCM220 and SCM440 steels using the developed optical system. The width of specimens between 13 and 17 mm can be hardened for a single pass scanning.