We wish to investigate the correct relation between the ellipticity in degrees measured by thorlabs camera and the retardation of any sample, which is delta n.

For this I put polarizer and HWP after BS in the LC path. Then I tune the input polarization to be linear, i.e ell is 0 +/-0.1 aqnd azi is 0+/-0.04 deg respectively. I don't know the reason of the large fluctuation in ell.

Then I put QWP after them infront of the camera. Then I record the azimuth and ellipticity at various angles of the QWP. The QWP was mounted on rotator mount and the data was saved at various positions of the rotator.

filename:C:\Users\atama\OneDrive\LC-Experiment\Measurement Data\Retarder\QWP\20240605\Thu, Jun 6, 2024 10-12-20 AM.txt

the last column in file saved the angle of the rotator