Laser control system for use in laser processing machine utilizing laser-induced plasma detecting system

A laser processing machine having a torch unit for adjusting focus condition and centering alignment with laser beams to be projected to an object, comprising:

• a photo detector detecting intensity of light generated by laser-induced plasma produced by applying laser beams on an object and generating a resultant detection signal of the light;
• and
• a control unit electrically connected to said photo detector for controlling a laser pulse signal for commanding generation of the laser beams to have an optimum pulse width and optimum pulse period effective in each pulse signal based on the detection signal, so that the optimized laser pulse signal is transmitted to a laser beam generator to automatically control the generation of the laser beams,
• wherein the pulse width of each pulse is controlled by the control unit so that the detection signal outputted from the photo detector has its peak values to be all equal to a constant level, and wherein the pulse period of each laser pulse signal is so controlled as to have a reference threshold level which is previously given by the material of the object.

A laser control method adapted in a laser beam machining process, comprising the steps of:

• detecting intensity of light generated by laser-induced plasma produced by applying laser beams on an object and generating a resultant detection signal of the light;
• and
• controlling a laser pulse signal for commanding generation of the laser beams to have an optimum pulse width and optimum pulse period effective in each pulse signal based on the detection signal, and then automatically control the generation of the laser beams,
• wherein the pulse width of each pulse is controlled so that the detection signal has its peak values to be all equal to a constant level, and wherein the pulse period of each laser pulse signal is so controlled as to have a reference threshold level which is previously given by the material of the object.