Five months have passed since my last cross-scan test results. 

Jitter and Scanline Error Resolution

The extended delay was primarily due to addressing extremely poor initial results from the jitter test, i.e. error along scanline. Resolving this critical issue required a deep dive and specific hardware/software adjustments. I will not outline all of the code optimizations but want to highlight two main changes:

1.  Mirror Position Adjustment: The physical position of the mirror was moved, allowing the laser's position to be measured at the start of the scanline instead of the end.
2.  Photodiode Trigger Algorithm Change: A key change was made to the algorithm governing the photodiode trigger timing. The algorithm was proposed by a LLM (https://github.com/hstarmans/hexastorm/blob/master/src/hexastorm/blocks/photodiode_debounce.py).
These fixes now allow for successful photodiode detection and consistent measurement. The table below shows the resulting timing statistics for each facet (there are four). It's hard to stratify samples. I now set a minimum i.e. 32 which can result in more samples for other facets. Each row corresponds with a different facet. They are ordered sequentially.

Experimental Notes

Operational Parameters:

Laser Power:  130/255, both channels of laser driver
Exposures: Four exposures are used per line.
Facets: All facets were used, testing confirmed that using a single facet did not improve the overall results.

Lines seem to wide in the image, spacing should equal line width,  I probably need to add an erosion operation.

Focusing Procedure:

Achieving accurate laser focus is critical. A white sheet of paper is placed on the exposure plane, and the laser is focused using a single channel of the laser diode driver at 133 a.u (digipot) to draw a test line. Successful focus is immediately confirmed by drawing a sharp, visible line (burning)

Future work

I need to pin facet data to certain facet, so I can use measurements to  correct for each facet.