Advice for the repair of a lab-style Melles Griot laser

Hey guys,

I have recently acquired a defective Melles Griot laser of the model 58-GHS-305-048. It is built to have an output power of 2.5W at 532nm. The gain crystal was cracked, while the pump diode (probably a 20W version) operates perfectly fine, and the doubling crystal as well as the output coupler are in good shape. I have bought a 3x3x4mm replacement Nd:YVO4 crystal (0.5% doping concentration), which has the HR@532+1064nm mirror deposited on its rear face. Because the original cavity was set up at an angle (refer to sam's laserfaq: http://www.repairfaq.org/sam/mghpgdl2.jpg), I have removed the SHG crystal and output coupler as well.

Now, I need to place the Nd:YVO4 crystal in the cavity and realign the other parts. Does anyone have advice on how to do it? My first thought was to shine a 532nm laser pointer through the front side and align all components one after the other so that the reflected beams all overlap. I didn't want to fire the pump diode up with the crystals in place, I am a little bit afraid of destroying the crystal with a wrong positioning..

Thanks in advance,

Alex :thanks:

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