I realigned the beam that should now propagate along (x,y) = with 0.06 deg deviation.
I reinstalled the polarization camera, updated the labview vi and found the qwp sample (previously measured by Hugo) as (x,y) = 322.75,156.1
measurement will be done with 50 averages/medians
calibration map with 1 mm step and 3 mm radius
measurement map with 2 mm step and 9 mm radius
0deg :
no sample : Thu, Sep 5, 2024 3-07-56 PM
sample : Thu, Sep 5, 2024 3-22-20 PM
15deg
no sample :Thu, Sep 5, 2024 4-19-34 PM
sample : Thu, Sep 5, 2024 4-26-27 PM
30 deg
no sample : Thu, Sep 5, 2024 4-45-38 PM
sample : Thu, Sep 5, 2024 4-52-12 PM
45deg
no sample : Thu, Sep 5, 2024 5-15-55 PM
sample : Thu, Sep 5, 2024 5-21-25 PM
60 deg
no sample : Thu, Sep 5, 2024 5-43-24 PM
sample : Thu, Sep 5, 2024 6-05-04 PM
75 deg
no sample : Fri, Sep 6, 2024 1-47-12 PM
sample : Fri, Sep 6, 2024 1-53-11 PM
There was issue with 0deg calibration file (empty..)
Using other files, together with a condition of Jones matrix homogeneity of theta_r > pi - 0.01 and otherwise using semi-homogeneous case for eta < eta_max we can still get the attached plot of the QWP efffective retardation.
With these conditions we use the couples (15/30, 15/45, 30/45).
The result is compatible with LC measurement (88.5 +/-0.6 deg) and with vendor specifications.
I'll repeat the measurements with 0deg input polarization and also compute Jones matrix, full diattenuation/retardation and rotation.
after waiting about 1h to let the laser stabilized :
0deg
no sample : Mon, Sep 9, 2024 10-26-56 AM
sample : Mon, Sep 9, 2024 10-32-56 AM
Adding these maps we now have (0/30, 0/45,0/60,15/30,15/45,30/45) couples and effective retardation attached to this entry.