We've seen plenty of uses for laser cutters over the years, and ours certainly churns out the parts at a fair old clip. Peter Walsh, however, is the first person we've seen using a laser cutter to produce optical lenses for use with low-cost lasers in educational programmes.
While Peter's project initially began as a means of creating low-cost component mounts for existing optical lenses, Peter and his team soon began trying out something new: cutting clear acrylic in a lens-like profile to see if it could affect the beam of a laser. To considerable surprise, it turns out they can - just like the more expensive lenses on which they are based.
Although traditional optical lenses are created by grinding the plastic or glass in three dimensions, a laser cutter can only modify material in two dimensions. The third dimension, in this case, is provided by the thickness of the acrylic material itself - and while it requires the laser to be lined up with the edge of the lens, it's amazingly effective at demonstrating how convex and concave lens shapes affect the path of the light passing through them, as well as how combinations of lenses interact.
In a comment on the Hackaday coverage of the project, Peter explained that the cutting files are not yet available on his project page due to issues with his CAD software failing to export smooth curves. Once resolved, Peter has promised to make the files readily available.
For younger students, we also have projects for teaching the basics. The lens profile set shown here can be used to demonstrate most of the basic principles of optics: positive and negative lenses, ray tracing, and even simple lens systems like the one shown below.