Laser beam machine

TL;DR: In this paper, a laser beam machine equipped with an auto-focusing function was designed to obtain an accurate focal point despite the displacement of the optical system of a machining laser or auto focus.

Abstract: PROBLEM TO BE SOLVED: To provide a laser beam machine capable of obtaining an accurate focal point despite of the displacement of the optical system of a machining laser or auto focus on account of change in the ambient temperature of the device SOLUTION: The laser beam machine 31 is equipped with an auto-focusing function and designed to machine a work 16 on a stage 17-19 by means of a machining laser beam 1 The machine is also provided with a thermometer 22 for detecting the temperature of the optical system of the machining laser 1 or the auto focus 12, a main controller 8 having an arithmetic part for determining a defocus quantity based on the temperature detected by the thermometer using the map of temp vs defocus quantity, and a stage controller 9 having such a function that this defocus quantity is given to the Z stage 18 as an offset quantity Consequently, according to the temperature of the optical system detected by the thermometer 22, the defocus quantity is determined on the basis of this temperature from the map of temperature versus defocus quantity to give this defocus quantity to the Z stage 18 as the offset quantity