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Size: 1595
Comment:
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Size: 1439
Comment:
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| Deletions are marked like this. | Additions are marked like this. |
| Line 21: | Line 21: |
| * VCO Driver Box (R. Abbott) | * [http://www.ligo.caltech.edu/docs/D/D980401-B1.pdf VCO Driver Box] (R. Abbott) |
| Line 24: | Line 24: |
| * PMC 35.5 MHz Frequency Reference Card (R. Abbott) * PMC Servo (by Karwoski, based on the R. Abbott original - modified by Rana/Jenne based on the Hartmut mods) * PMC RFPD (old LSC kind by Dale Ouimette) |
The FSS stabilizes the fluctuations in the laser frequency by comparing it to a quiet Reference Cavity. The light is picked off just before it goes into the Pre Mode Cleaner, sent through a EOM and the frequency shifting AOM and then into the RC.
The FSS actuates on the NPRO Piezo (called the FAST path) and on a phase correcting Pockels cell (which is faster than the FAST path).
To lock:
Run the FSSAutolock script from the C1PSL_FSS screen (under the yellow ! button).
The FSS has a /SLOW PID servo which offloads the FAST (PZT) path by feeding back to the NPRO's SLOW input. The FAST has a rough calibration of 5 MHz/V while the SLOW is more like 5000 MHz/V. It has a ~0.1 Hz pole and so that's why its called SLOW.
List of FSS Related Electronics Schematics
- TT FSS Box (by Schwinberg, Myers, and Savage, based on the Rich Abbott original)
- TT ISS Box (by Flavio Nocera w/ lots of prodding from Rana)
[http://www.ligo.caltech.edu/docs/D/D980401-B1.pdf VCO Driver Box] (R. Abbott)
- FSS RFPD (old LSC kind by Dale Ouimette)
- Variac on the HEPA (D. Busby's handiwork)
See also PSL.
attachment:C1PSL_FSS.png
References
[http://www.ligo.caltech.edu/docs/P/P960008-10.pdf P960008-10]: Improved Multistage Wide Band Laser Frequency Stabilization, by Seiji Kawamura, Alex Abramovici, Mike Zucker (1996).