Yuhang, Eleonora
Some measurement on the local control noise was done, in order to compare their performamces to those of AA.
This is for the input mirrors. The calibration in rad/count is (reported in entry #1874) used for this measuremnt is:
| Pitch | Yaw |
| 0.038 [urad/count] | 0.027 [urad/count] |
We recall that that Input and end mirrors oplev use commercial PSD (thorlabs PDP90A) and the signal is amplified by a factor 100 with a SR560 and filtered with a 2nd order lowpass with cut-off frequency 100 Hz.
PIC 1: Piitch signal compared with ADC noise and dark noise (the noise measured when the laser is switched. Factor 100 amplification from SR560 still present)
PIC 2: Yaw signal compared with ADC noise and dark noise (the noise measured when the laser is switched off. Factor 100 amplification from SR560 still present)
PIC 3: Piitch signal compared with ADC noise and signal withoud the factor 100 amplification (red curve should be multipplied by a factor 100 to have the good calibration)
PIC 4: Yaw signal compared with ADC noise and signal withoud the factor 100 amplification (red curve should be multipplied by a factor 100 to have the good calibration)
