| 摘要 |
PURPOSE:To improve the accuracy of laser beam processing by providing two sets of far IR radiation sensors, measuring the temps. at the respective points of a condenser lens and controlling the focal position of the lens in accordance with the computed thermal deformation quantity of the lens. CONSTITUTION:An automatic turn stable 9 having a pulse motor is provided above the condenser lens 2 and to sets of the far IR radiation sensors 8 are disposed. A 1st sensor A and the 2nd sensor B scan the entire surface of the condenser lens 2 in accordance with the regions A, B and measure the temps. at the respective points. The measured temp. data is inputted to a computer having thermal analysis software, by which the thermal deformation quantity and change quantity of the focal length of the lens 2 are calculated. The pulse motor 20 controls the lens position in accordance with the results of the calculation so as to focus the laser light 1 to the work 3. Since the focal length of the lens 22 is subjected to the optimization control at all times, the accuracy of the laser beam processing is improved. |
