Converting STL file to series of layered PBM (bitmap) file

[panthers8913]

I'm not so sure about the PBM format, but you can use PrusaSlicer with an MSLA printer configuration to slice 0.050 mm layers, which are then output to a Prusa compatible file format. Once in that format, rename the extension to .ZIP, then extract the files within. I've done this with the slicer settings to 6.35 mm. I was surprised the slicer accepted such a layer thickness, but the results were then ready for cardboard cutting on a laser. The files are .PNG bitmaps, which appear to meet your requirements.

Thank you! This was extremely helpful! This was exactly what I was looking for.