How Does Laser Etching Work?
September 8, 2009 | tags | views
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A laser engraving machineThe process of laser engraving requires a laser engraving machine. Advanced technology that can be programmed to move the laser in a distinct pattern with a constant laser beam intensity and timing.
The 'trace' of the pattern that the engraver wishes to have etched on to the material is programmed in to laser engraving machine. The 'trace' is designed so the laser beam only passes over each area once. 'Overlap' can result in certain points having a deeper etch than other points.
Once the 'trace' is programmed in to the laser engraving machine, the laser moves on an X and Y axis, etching the design or pattern in to the material.Laser Ablation
- The most common method of laser etching is laser ablation and often involves the use of an excimer laser.
An excimer laser is an extremely precise, extremely intense ultraviolet laser that is also used for LASIK eye surgery.
Excimer lasers are considered ideal for etching and engraving since instead of just 'burning' the material, they ablate it.
Laser ablation is when a high intensity pulse of energy hits a material and essentially 'dissolves' the material, causing it to evaporate. Since the pulse is so short, and the evaporation of the material is nearly instantaneous, there is very little heat produced. This makes this process ideal for engraving, as an excimer laser can be used on delicate or heat-sensitive materials like glass, plastic, wood and jewelry.
In laser etching, as the laser passes over the material, it is ablating the material, creating a constant depth and allowing fine detail.Finish
- After the surface of the material is done being etched, the machine will blow air across it. This is done because the evaporated material from ablation may be an irritant.
For metallic materials, a finish is often applied to the final product to prevent corrosion in the future.