Laser-Based Method and System for Marking a Workpiece

A system for marking a workpiece at a marking location by infusing colorant into targeted surface material within a region of the workpiece via laser-induced chemical etching, the system comprising:

• a laser subsystem for generating a pulsed laser output having a plurality of laser pulses;
• a transport subsystem including a medium containing the colorant mounted immediately adjacent the marking location to transfer the colorant from the medium to the targeted surface material of the workpiece upon impact by the pulsed laser output;
• and
• a delivery subsystem for irradiating the medium and the targeted surface material in the region with the pulsed laser output to melt the targeted surface material to obtain molten material and to transfer the colorant from the medium to the molten material in a predetermined pattern, the molten material allowing the transferred colorant to thermally diffuse into and chemically bond to the molten material wherein each laser pulse creates a microtextured colorized spot of material on the workpiece and wherein the microtextured colorized spots of material create a marked region of the workpiece.

A system for marking a workpiece having a specular metal surface at a marking location by infusing colorant into targeted surface material within a region of the workpiece via laser-induced chemical etching, the system comprising:

• a laser subsystem for generating a pulsed laser output having a plurality of laser pulses;
• a transport subsystem including a medium containing the colorant mounted immediately adjacent the marking location to transfer the colorant from the medium to the targeted surface material of the workpiece upon impact by the pulsed laser output;
• and
• a delivery subsystem for irradiating the medium and the targeted surface material in the region with the pulsed laser output to melt the targeted surface material to obtain molten material and to transfer the colorant from the medium to the molten material in a predetermined pattern, the molten material allowing the transferred colorant to thermally diffuse into and chemically bond to the molten material wherein each laser pulse creates a microtextured colorized spot of material on the specular metal surface of the workpiece and wherein the microtextured colorized spots create a marked region which shows significant roughness and eliminates at least strong reflection components.

A system for marking a workpiece at a marking location by infusing colorant into targeted surface material having a thermal diffusivity within a region of the workpiece via laser-induced chemical etching, the system comprising:

• a laser subsystem for generating a pulsed laser output having a plurality of laser pulses, each of the pulses having a pulse width;
• a transport subsystem including a medium containing the colorant mounted immediately adjacent the marking location to transfer the colorant from the medium to the targeted surface material of the workpiece upon impact by the pulsed laser output;
• and
• a delivery subsystem for irradiating the medium and the targeted surface material in the region with the pulsed laser output to melt the targeted surface material to obtain molten material and to transfer the colorant from the medium to the molten material, the molten material allowing the transferred colorant to thermally diffuse into and chemically bond to the molten material wherein each laser pulse creates a microtextured colorized spot of material on the workpiece and wherein the microtextured colorized spots of material create a marked region of the workpiece and wherein energy from the laser pulses is transferred to the area around each of the spots via thermal diffusion and wherein the thermal diffusion is based on the pulse width of the pulses and the thermal diffusivity of the surface material.