Raster and vector files are different types of design file which are required for different types of laser engraving. The main difference between them is that raster graphics are composed of pixels, while vector files are made up of paths or lines.
The differences between the modes required for laser engraving is the axels and parameters used during processing.
Raster engraving is the standard process for engraving. The file is printed line by line, as it is when processed with inkjet printers.
How does the laser processing work?
A raster file is made up of pixels (bitmap). The laser engraving process engraves the file line by line, point by point. This is similar to how a printer would apply ink, but the material is removed pixel by pixel with a laser machine, while a printer would apply ink pixel by pixel. This is a "bi-directional" process in which engraving is done in alternating fashion in both directions.
The speeds of the two axles are different during laser engraving. The x axle (where the laser head is attached) moves at high speed, while the y axel moves at a slower speed. For raster laser engraving, the PPI parameter (pulses per inch) is selected in the Trotec JobControl® laser software. This is important, because it controls the density of the laser points. Read more about the parameter definition.
Vector engraving, often referred to as “scoring,” is a process where the file to be printed is a graphic file consisting of vectors (lines and curves of a geometry), marked as hairlines in the graphics.
When the file is imported from the chosen graphics program to the JobControl® laser software, the outline is identified as vector engraving. Vector by vector is traced by the laser and then laser engraved. The axles move simultaneously and slower when vector engraving than when raster engraving.
The process itself is the same as in laser cutting; the difference being the power setting. When a low power setting is chosen, the line is “scored” as laser engraving, while higher power settings produce vector cuts.
Find out how to quickly determine optimal laser parameters.
Vector engraving is preferable for applications which only require thin lines to be engraved, and results may be produced quicker than other methods. For laser cutting this method is the only one used.