SpectraPhysics MaiTai laser#
Support engineer is Jian Lu (Jian.Liu@newport.com).
Coherent Vision-S laser#
Service contract sales and administration: Annette Davis (p. 800-367-7890 x4 | f. 408-404-0898, Annette.Davis@coherent.com).
Technical Support (+1 800 367 7890, customer.support@coherent.com).
A field engineer that covers the Boston area is Falk Preller (Falk.Preller@coherent.com).
Laser monitoring (all users)#
Keep an eye on the laser power, the output stabiliy, the time it takes to mode-lock, and the shape of the spectrum. Below is an example of laser showing signs of continuous-wave (CW) breakthrough, something that we don’t want to see! If you notice something strange, try 800 nm and see if the laser can mode-lock. Since more pump laser power is required for this wavelength, you might be able to detect something abnormal.
If the laser overheats#
- In case of laser shutdown, check the chiller temperature. When the chiller is working properly and the room temperature is acceptable, the chiller temperature shouldn’t fluctuate more than a few tenths of a degree from the 21 deg C set point. The laser will shut down automatically if it overheats. If this happens…
- Put the laser into standby.
- Check the room temperature in the curtained-off section of the room where the laser is located. if the room is very hot this will challenge the chiller. The system is designed to handle stable room temperatures betweeen 20 and 25 deg C. If the room is too hot or fluctuating rapidly, this will overwhelm the chiller. In this case, check the portable AC unit and/or we need to discuss how to cool the room better.
- Make sure the chiller is actually chilling. Double check the manual, but the front panel should probably display a “C” in front of the temperature.
- Make sure there’s nothing obstructing air flow in front of and behind the chiller
- Replace the chiller fluid if this hasn’t been done recently. First make sure we have extra chiller fluid (this is the pink liquid in the gallon bottles that should either be next to the chiller or under the sink in that room). For the SpectraPhysics laser, there should be a red/orange hose on the drying rack next to the sink that connects to the valve on the front of the chiller. The old fluid will drain out of the hose once you connect it, so get a bucket to collect the old chiller fluid. Disconnect the hose and add new chiller fluid through the fill port with the black screw cap. There’s a line that marks the max level. To replace the fluid filter, check the manual, but there’s a thing on the back of the chiller that the filter lives in that you can unscrew, and you should just be able to pull off the filter and put in a new one. Check the manual for whether the chiller should be off for this.
- The first few times you turn on the laser after you’ve done these things, watch the chiller temperature and the laser start-up for 10-15 minutes to make sure there are no abnormalities.
Regular maintenance (2p czars, every 6 months)#
- (SpectraPhysics/Coherent) Upon coolant refill, filter change, and desiccant checkup, please log the date and other information in the following spreadsheet: https://docs.google.com/spreadsheets/d/1jOEDgrGvGuxA5CWemMK9JQHFfwA2CuT7d4qxU9F2hWU/edit#gid=0
- (SpectraPhysics/Coherent) Change the coolant in the chiller. We have a container of extra coolant in the 2P room. Unscrew the top cap on the small black chiller (this is the smallest of coherent devices), pour out the old coolant and pour in the new coolant. The temperature should be set to 20°C. While you’re at it, clean the filters on the sides.
- Laser coolant is a hazardous chemical waste, see note for disposal of it.
- (SpectraPhysics/Coherent) Check the status of the desiccant by opening the recirculating unit. Replace if the color of the desiccant is starting to turn pink.
- (SpectraPhysics) Specific maintenance / replacement instructions sees the following user manual:
- (Coherent) To prevent laser setting from getting stuck at a local optimum, it’s better to test the laser at different wavelengths once in a while. Falk recommends that we let the laser emit the wave length to different ones from what we usually use every 6 months ( <1 hour procedure). This could be done manually by simply typing in a new value (e. g. 800 nm), but if you want to do it more systematically, click “Tune” tab and set the sweep range and the step size.
