Low cost dot lasers

2D cutting plotters need a reference on the material that has to be cut.  A dot laser with a known, fixed position offset to the cutting tool helps check if the material to be cut is placed correctly.   Respectively if the cutting head starts at the right position, laser points can be used to align objects that lack straight or perpendicular outlines.  Three points may mark a circular outline.  If an object has an irregular outline or distinctive features like grooves, gaps, recesses or mechanical marks, two or more laser points may define the position.  

Further information Low Cost OEM Modules (lasercomponents.com)