|
⇤ ← Revision 1 as of 2009-03-26 10:05:43
Size: 916
Comment:
|
Size: 949
Comment:
|
| Deletions are marked like this. | Additions are marked like this. |
| Line 11: | Line 11: |
| ==== Rough ideas ==== | ==== Basic ideas ==== attachment:CircuitExample.png |
Multiply Resonant EOM
Introduction
EOM (Electro-Optic Modulator) is a device to modulate the phase/polarization of a laser beam by an electric voltage signal. (http://www.rp-photonics.com/electro_optic_modulators.html) The main use of EOMs in LIGO is to add phase modulation sidebands to the main laser beam. Those sidebands are necessary to extract the information of the positions and orientations of the mirrors. For the advanced LIGO style length sensing scheme, we need two + one sidebands (i.e. three). The first two are used for the length and alignment sensing of the main interferometer. The last one is used for controlling the mode cleaner. The goal of the project is to design the double or triple resonant circuit to use with an EOM so that we can apply phase modulations at multiple frequencies with one EOM crystal.
Basic ideas
attachment:CircuitExample.png
attachment:TripleResonance.png