Characterizing an unknown eliptical polarization

[Blanchdog]

Homework Statement

See Uploaded image

Relevant Equations

Jones Calculus: https://en.wikipedia.org/wiki/Jones_calculus

In reality I don't have access to the lab thanks to covid, so I was told that the exiting beam is linearly polarized at +12 degrees when the waveplate is rotated to +70 degrees. I tried plugging these numbers in but got back a complex number for the first component in the Jones vector, when it should have been a real, positive number. Also, how would a polarizer alone reveal the elipticity and directions of the major and minor axes?

 

[jbsteele]

A polarizer alone will not reveal the ellipticity and directions of the major and minor axes. To do this, you need to measure both the power transmitted through the polarizer and the degree of polarization (the ratio of the power transmitted in the two orthogonal directions). You can then calculate the Jones vector from these two measurements. It sounds like the numbers you were given were for a waveplate rather than a polarizer, so that may explain why you got a complex number for the first component in the Jones vector.