Development of Micormirror Laser Scanning Mechanism for Laser Marking/Engraving/Etching System

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Laser marking/engraving/etching (the term is represented by "laser marking" thereafter) uses a laser beamacross the surface of a material to alter the property (e.g., color), or remove the materials to a certain depththrough vaporization/melting, such as to form desired patterns. It has been widely used in fabrication andconsumer product industries. A laser marking system consists of the laser source (e.g., CO2 laser, fiber laser,Nd:YAG or Nd:YVO laser), the laser beam vector scanning mechanism and controlling software. The laserbeam scanning mechanism is traditionally comprised of two galvanometer mirrors or two servo/stepper motordriven mirrors. It also includes other components such as encoders, driving cards, heatsinks and a powersupplier. The total size is 3 ~ 4 liters. The cost is about USD 2500, which is ~ 50% of the total laser marking.Lumicision Inc. is a GTA company (located in Richmond Hill) and specializes in manufacturing lasermachining machines and providing laser marking service. After the company entered this market for a fewyears, they realized the traditional laser scanning mechanism in their laser marking machines is too bulky andtoo expensive. The company has been long looking for an alternative solution of much lower cost and smallersize to the traditional laser scanning mechanism in their laser marking machines.This application proposes a solution to address the above problem, i.e., using micromirrors to vector scan thelaser beam to replace the traditional laser scanning mechanism in the laser marking machine. The micromirrorhas much smaller/simpler structure and driving circuit than traditional galvanometer or servo/stepper motorsdriven mirrors because the micromirror's mass is very small, which requires every little power to drive withoutneeding any heatsink. The micromirror based laser beam scanning mechanism is about 0.05 liter or less, whichis ~ 50 times smaller than that of the traditional design. In addition, micromirrors are suitable for massfabrication, i.e., hundreds or thousands are fabricated on one wafer at the same time, which leads to very lowunit mirror price, e.g., 10s dollars. The cost including the micromirror and the driving/control circuit is one