I am now explore the possibility of my Lazer cutter.
From now, 100mW lazer can be used to cut paper, vinyl adhesive sheets...
but I found that the same structure can also be used as pen plotter.
Just take off the lazer diode and insert a pen.
In this video, the outcome is not very good because I did not screw the pen tightly. (It is made of plastic and I don't want to broken it)