Coherent Verdi issues

[macona]

Pretty sure it was bad diode.

[Loic74650]

Trying to revive this again… did you sort this problem? I might have the same issue too, caused by a sudden shift in the wavelength. Thanks.

So actually yes, I solved my problem. It wasn't the diodes. My problem was that I played a bit (a dangerous thing to do) with the menus and EEPROM contents of the controller while in "maintenance" mode and must have wrecked something. In the end I went through the RESET procedure of the laser head, then through all the calibration procedures again and that solved it.

In your case, I would:

1/ go through an LBO temp optimization procedure. The automated way never worked for me, so I would put the laser controller in maintenance mode, then in current control mode, start the laser at an intermediate current level, then scan a large range of temperatures of the LBO while monitoring the laser power output. The Coherent VERDI software is very useful for this

2/ go through the FAP modules temp optimization procedures. The automated way never worked for me either, so I would put the laser controller in maintenance mode, then in current control mode, start the laser at an intermediate current level, then scan a large range of temperatures of the diodes while monitoring the laser power output. The Coherent VERDI software is very useful for this, same as above

3/ (if 1/ not successfull) ensure the diodes are working properly (/!\ hat requires tooling and IR eye protection /!\). Basically you open up the controller housing, unplug a fiber from a FAP module, place an optical power meter at the exit of a diode (which can handle up to 50W), put on the safety goggles, place the laser in maintenance mode, place the diodes in current mode, then slowly ramp up the current on the diodes to see if you get the intended optical power out of the FAP modules

4/ if 2/ shows that the diodes are fine but still no output, I would go through a head reset procedure. Start however by exporting/recording all laser parameters with the Coherent VERDI software.

All steps above at your own risk, it normally requires a skilled, trained and tooled engineer

[laserchs]

Thank you. Unfortunately, I am a novice. I did try the LBO temperature optimization through command prompt, but that did not help. Wanted to run FAP-I optimization but not sure how to access the diode optimization menu/service login on GUI. Also forgot to add in my earlier post, I am using this Verdi V18 to pump a chameleon, my pump is around 12-14W, but the chameleon head stays at 0mW and is giving me a lasing fault (error 52; low output power). All which started to happen just recently when laser wavelength was changed suddenly while it it was trying to modelock.

[Loic74650]

Sorry, I don't know the Chameleon system, only the Verdi.