Patent ID: 6075220
Filing Date: 2000-06-13
Classification: B23K

Abstract:
An apparatus for real-time determination of the depth of penetration of a weld, comprising:means for applying a pulsed laser beam to a workpiece to form a weld, said means also producing a trigger pulse at the initiation of the application of the beam;means to generate a measurement light beam at a known distance above the weld, said light beam being attenuated by the presence of a rising vaporization plume above the weld;means to detect said light beam for measuring a change in light intensity caused by the plume and generating an electrical output signal; andmeans for analyzing said electrical output signal to determine the velocity of said vaporization plume by dividing said known distance by the time between the trigger pulse and the generation of the electrical output signal, said velocity being a function of the depth of penetration of the weld.