The goal of this project is to develop a PCB machine which can create a track width smaller than 100 micrometers, i.e. 4 mil. The PCB machine should be fast and have a writing speed greater than 3 meters per second. The machine uses a transparent instead of a reflective polygon to move a laser beam. The main advantage is that an expensive f-theta lens is not needed and the projection is tele-centric.
The current version of the Hexastorm has the following specifications:
- wavelength: 405 nm
- rotation frequency: up to 21000 RPM, current 2400 RPM
- line speed: up to 34 meters per min @ 21000 RPM
- spot size FWHM: circular, 25 micrometers diameter
- cross scanner error: 40 micrometers (error orthogonal to scanline)
- stabilization accuracy scanning direction : 2.2 micrometers (disabling/enabling scanhead)
- jitter: 35 microns (error parallel to scanline)
- laser driver frequency: 2.6 MHz
- maximum scan line length: 24 mm
- typical scan line length: 8 mm
- optical power: 500 mW
- facets: prism has 4 facets
- Beaglebone green
- Firestarter cape
An image can be uploaded to the scanner and exposed on a substrate.
An exposure result on cyanotype paper is shown below.
Resolution looks to be around 100 microns. Stitching still needs to be fixed, results in white lanes.
An exposure goes as follows (for the result see above). The new scan head will not use a mirror and is oriented vertically.