1 / 14

Monitoring laser

Monitoring laser. Contents : I Presentation II Safety &trigger III Analysis IV Next actions. David BAILLEUX. Monitoring laser. 1. YLF. Ti:S. Krypton lamp. YLF. Ti:S. Output. I Presentation. Principe: optical pumpage. YLF = Yttrium Lithium Fluoride. YLF Ti:S

guy
Download Presentation

Monitoring laser

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Monitoring laser Contents : I Presentation II Safety &trigger III Analysis IV Next actions David BAILLEUX Monitoring laser 1

  2. YLF Ti:S Krypton lamp YLF Ti:S

  3. Output I Presentation Principe: optical pumpage.. YLF = Yttrium Lithium Fluoride YLF Ti:S  527nm 440nm Pulse energy 10mJ 1mJ Pulse width 40n 40ns Pulse power 250kW 25kW David BAILLEUX Monitoring laser 3

  4. I Presentation Cooling: Inlet Transfo (110V) Pump + heat exchanger Outlet David BAILLEUX Monitoring laser 4

  5. I Presentation Laser Settings Remote controls: - wavelength - energy • Record data for 2 lasers : • histogram and history • energy • pulse width • pulse center • wavelength Waveform Display David BAILLEUX Monitoring laser 5

  6. III Safety, trigger • Safety: • A TTL level input is required on the safety module. • No TTL signal  shutter of YLF laser closed • This TTL signal is off if : • - the door is opened, • the main fiber is broken, or no light on pin diode. An interlock is provided to close the laser shutter (pump) in case of unexpected opening of the laser room door. The interlock also functions if optical fibers were accidentally broken or removed. This is achieved by the level 2 TTL input, provided by Fanouts … TTL signal at high level if the level fanouts receive laser pulse. David BAILLEUX Monitoring laser 6

  7. III Safety External trigger : Timing signal form YLF laser External trigger Level TTL signal David BAILLEUX 7

  8. SECURITY LASER FIBRE HS FIBRE OK TRIGGER = Timing signal EVT 4 us PIN NIVEAU 2 GENE porte rapide *T END of porte Security laser (TTL level) GENE T0 (manual switch) No event  no more light  security laser = low level  shutter closed *T > tps de transmission ds las fibres + tps de propagation du signal ds les cables.

  9. III Analysis Results after calibration 26 A working point Neutral density filter 1/100 YLF  2000 mW Energy from 0 to 100 %, soft 0 mW  Output Ti:S 1,1 mW Ti:S  110 mW David BAILLEUX Monitoring laser 9

  10. /mean=3 % /mean=1 % III Analysis YLF Old lamp (31 August) /mean= 1.6 % /mean= 2.1 % New lamp Plot from 2 Oct (27 Oct) YLF ENGY YLF FWHM David BAILLEUX 10

  11. /mean= 4.9 % /mean= 4.3 % Ti:S /mean=7.7 % /mean=7.5% Old lamp (31 August) New lamp Plot from 2 Oct (27 Oct) Ti:S ENGY Ti:S FWHM David BAILLEUX 11

  12. III Analysis In August Variations p-p: 40% With new lamp (27/09) End of stabilization Variations p-p: 5% 66 h David BAILLEUX 12

  13. III Analysis With new lamp Long term Variations p-p: 10% 10 j David BAILLEUX 13

  14. Summary • Lamp has to be replaced every 2000 hours (83 days), •  Degradation is about 10% at 1000 h and 20% at 2000 h • Wavelength : problem from 440 to 500 nm : no light at 500 nm • fine tuning needed, service from Quantronix (similar problem in Caltech) • Forecast : ready in 2 weeks ? • Next year: • software improvement: Now data are recorded every 1 s (scope limitation) • Laser events = 2000/mn  DAQ record 20 events/mn (0.3 Hz) data during all test beam probe for temperatureinside the laser barrack new laser installationFeb 2003 ?

More Related