@dc42 These Epsilon lasers was our inspiration for trying to do some similar but masivelly cheaper. They are very good but outrageously expensive, typical gadget that would be good for hacking.
We tried with two VL6180 chips in oposed angles and know distances to triangular the measures and divide accuracy. Temperature was not the main concern, so we tried to fire from 10cm away the hotend. The best resolution we get was near a milimeter, too much for autolevel or accurate z-offset findings.
At that time we was even talking about this project with researchers from the laser applications laboratory of the UDC University, as they are clients and friends, and they found it interesting and in a way, doable. But we ended up leaving it to focus on more "prosaic" things.
I still keep some on my desk.
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