I recently got a couple used Coherent Sapphire 488-20 lasers, one works great, the 2nd unit has some really strange behavior, initially it will power up and output
full 20mw of power, but after about 30sec to a minute it will just shut down, and restart but will only output about 3mw of power. I pretty much assume the pump diode
is on it's last legs but was wondering how much more juice I could squeeze out of this unit, it appears still capable of 20mw output verified with a lasercheck question
is how to disable or override whatever safety mechanism is causing the laser to shut down, wondering if anyone has any experience hacking these lasers and controllers?
I did do some research and the closest thing I found that was helpful is this page. (http://redlum.xohp.pagesperso-orange.../Sapphire.html)
I attempted to increase the headroom for the diode current hoping it would help, I tried 0.2ohm and 0.5ohm resistor in parallel with the sense resistor, but it didn't
appear to change anything, same problems.
I also have serial control over the laser, here is a log of basic startup and operation behavior.
I will continue to probably mess with the system untill I kill it, might learn a thing or 2 about these lasers in the process, I'll post my findings along the way if I makeCode:Sapphire:0-> ?lt Sapphire 20mW Sapphire:0-> ?wave 488 Sapphire:0-> ?sv 6.710 Sapphire:0-> ?hh 3591:52 Sapphire:0-> ?maxlp 22.000 Sapphire:0-> ?minlp 0.500 Sapphire:0-> ?nomp 20 Sapphire:0-> L=1 Sapphire:0-> ?p 19.990 Sapphire:0-> ?c 1.748 <----------- laser shuts off (about 30sec of full power output) Sapphire:0-> ?ff 0 Sapphire:0-> ?FL Fault(s): None <----------- turn main power off/on Sapphire:*-> ?p 0.814 Sapphire:*-> ?sp 20.000 Sapphire:*-> ?c 0.008 Sapphire:*-> ?c 1.703 Sapphire:0-> ?p 20.000 Sapphire:0-> ?c 1.710 Sapphire:0-> ?c 1.709 Sapphire:0-> ?c 1.710 Sapphire:0-> l=0 Sapphire:0-> ?dt 19.997 Sapphire:0-> ?bt 22.041 Sapphire:0-> ?c 0.009 Sapphire:0-> ?bt 23.185 Sapphire:0-> l=1 Sapphire:0-> ?c 1.738 <--------------- 5sec full output then shuts off Sapphire:0-> ?c 0.008 Sapphire:0-> l=1 Sapphire:0-> ?p 20.000 <--------------- 3sec full output then shuts off Sapphire:0-> l=1 Sapphire:0-> ?c 1.800 Sapphire:0-> ?p 1.990 Sapphire:0-> ?p 2.157 Sapphire:0-> ?p 2.324 Sapphire:0-> ?ff 0 Sapphire:0-> ?FL Fault(s): None <-------------- laser stays on now, but with only 2.3mw output power
any progress... any input or suggestions is appreciated! thanks in advance...