NAOJ GW Elog Logbook 3.2
[Marc, Shalika]
Labview modifications :
A new sub-vi has been created 'step voltage' that scan LC1 voltage from min to max voltage with user defined step. Once it reaches the maximum, the LC2 voltage is increased by the same step.
The time of each iteration was defined to have 1 data / step.
There is some little issue sometimes where Vlc2 > Vmax... Maybe du to our exit condition that does not take into account the finite numerical resolution we might have...
Controller issue
We found out that when the Kinessis software is started after Labview, the voltage controller of LC1 can not be used..
This is indicated in our vi front panel if the 'controller' LED is off.
This was the case for previous measurement and is now corrected.
First polarization state generation!!
Figures 1 and 2 are respectively measurement and simulation.
They agree quite well with each others!
We need to improve the fit by taking more measurement (was done every 10 deg rotation) and improve the simulation by taking the temperature and extinction ratio of LC1.
The step voltage sub vi was fixed (misplaced connection) so I will spend the week end trying to generate and analyze 40 000 polarization states.
I'm scanning each LC voltage from 0 to 10V with 0.05V increment, at 30degC.
The output polarizer angle conversion is so that 298.25deg is our 0deg (ie cross polarizers configuration). The output polarizer will be rotated by 5deg increment.
Note that for tprevious measurement there is a -5deg offset with cross polarizer angle as it was assumed to be 293.25 deg.